Doxycycline

In case of overdosage, discontinue medication, treat symptomatically and institute supportive measures. Dialysis does not alter serum half-life, and it would not be of benefit in treating cases of overdosage.

Doxycycline is a prescription medication used to treat certain bacterial infections and to prevent malaria infections. Doxycycline belongs to a group of drugs called tetracycline antibiotics, which prevent the growth and spread of certain bacteria by inhibiting protein production.

This medication comes in tablet, capsule, and oral suspension (liquid) forms, and is typically taken once or twice a day. The tablets and capsules should be taken with a glass of water, with or without food. However, taking doxycycline with milk or food may decrease the amount of medication absorbed from your stomach. Do not crush or break the delayed-release tablets or capsule.

Doxycycline also comes as a gel to be administered by a dentist in a clinic setting.

This medication is also available in an injectable form to be given directly into a vein (IV) by a healthcare professional.

Common side effects of doxycycline include nausea, sunlight sensitivity, and rash.  

Oral/Injectable:

Doxycycline is a prescription medication used to treat certain bacterial infections and to prevent malaria infections. Doxycycline treats bacterial infections of the lungs, respiratory tract, skin, genitals, and urinary tract. Doxycycline is also used to treat Lyme disease, anthrax, and acne. It may also be used by your dentist to treat periodontitis (inflammation within the mouth).

This medication may be prescribed for other uses. Ask your doctor or pharmacist for more information.

• Store doxycycline at room temperature, below 86°F (30°C).
• Keep this and all medications out of the reach of children.

Doxycycline is a tetracycline antibiotic. It fights bacteria in the body.

Doxycycline is used to treat many different bacterial infections, such as urinary tract infections, acne, gonorrhea, and chlamydia, periodontitis (gum disease), and others.

Doxycycline is also used to treat blemishes, bumps, and acne-like lesions caused by rosacea. Doxycycline will not treat facial redness caused by rosacea.

Doxycycline may also be used for purposes not listed in this medication guide.

Due to oral doxycycline’s virtually complete absorption, side effects to the lower bowel, particularly diarrhea, have been infrequent. The following adverse reactions have been observed in patients receiving tetracyclines.

Gastrointestinal

Anorexia, nausea, vomiting, diarrhea, glossitis, dysphagia, enterocolitis, and inflammatory lesions (with monilial overgrowth) in the anogenital region, and pancreatitis. Hepatotoxicity has been reported. These reactions have been caused by both the oral and parenteral administration of tetracyclines. Rare instances of esophagitis and esophageal ulcerations have been reported in patients receiving capsule and tablet forms of drugs in the tetracycline class. Most of these patients took medications immediately before going to bed. (See DOSAGE AND ADMINISTRATION.)

Skin

Maculopapular and erythematous rashes, Stevens-Johnson syndrome, toxic epidermal necrolysis, and erythema multiforme have been reported. Exfoliative dermatitis has been reported but is uncommon. Photosensitivity is discussed above. (See WARNINGS.)

Renal Toxicity

Rise in BUN has been reported and is apparently dose related. (See WARNINGS.)

Hypersensitivity Reactions

Urticaria, angioneurotic edema, anaphylaxis, anaphylactoid purpura, serum sickness, pericarditis, and exacerbation of systemic lupus erythematosus.

Blood

Hemolytic anemia, thrombocytopenia, neutropenia, and eosinophilia have been reported with tetracyclines.

Other

Intracranial hypertension (IH, pseudotumor cerebri) has been associated with the use of tetracyclines. (See PRECAUTIONS - General.)

When given over prolonged periods, tetracyclines have been reported to produce brown-black microscopic discoloration of the thyroid gland. No abnormalities of thyroid function are known to occur.

Read the entire FDA prescribing information for Monodox (Doxycycline)

You should not take this medicine if you are allergic to doxycycline or to other tetracycline antibiotics such as demeclocycline (Declomycin), minocycline (Dynacin, Minocin, Solodyn, Vectrin), or tetracycline (Brodspec, Panmycin, Sumycin, Tetracap).

To make sure you can safely take doxycycline, tell your doctor if you have any of these other conditions:

• liver disease;
• kidney disease; or
• asthma or sulfite allergy.

If you are using doxycycline to treat gonorrhea, your doctor may test you to make sure you do not also have syphilis, another sexually transmitted disease.

FDA pregnancy category D. Do not use doxycycline if you are pregnant. It could harm the unborn baby or cause permanent tooth discoloration later in life. Tell your doctor right away if you become pregnant during treatment.

Doxycycline can make birth control pills less effective. Ask your doctor about using a non hormone method of birth control (such as a condom, diaphragm, spermicide) to prevent pregnancy while using doxycycline.

Doxycycline passes into breast milk and may affect bone and tooth development in a nursing baby. You should not breast-feed while you are taking doxycycline.

Children should not use doxycycline. Doxycycline can cause permanent yellowing or graying of the teeth in children younger than 8 years old.

Semisynthetic tetracycline antibiotic.1

Available as 40-mg capsules (Oracea) containing 2 types of doxycycline beads (i.e., 30 mg as immediate-release beads and 10 mg as delayed-release beads).1

Doxycycline is used to treat bacterial infections in many different parts of the body. It is also used to treat pimples and abscesses (usually on the face) that are caused by rosacea, also known as acne rosacea or adult acne.

Doxycycline delayed-release tablets and tablets are also used to prevent malaria and treat anthrax infection after possible exposure and other conditions as determined by your doctor.

Doxycycline belongs to the class of medicines known as tetracycline antibiotics. It works by killing bacteria or preventing their growth. However, doxycycline will not work for colds, flu, or other virus infections.

doxycycline is available only with your doctor's prescription.

Take doxycycline exactly as directed by your doctor. Do not take more of it, do not take it more often, and do not take it for a longer time than your doctor ordered. To do so may increase the chance of side effects.

doxycycline comes with patient instructions. Read and follow the instructions carefully. Ask your doctor if you have any questions.

If you are using delayed-release tablets or tablets:

• It may be taken with food or milk, if it upsets your stomach.
• You may take doxycycline by breaking the tablets. Hold the tablet between your thumb and index fingers close to the appropriate score (separation) line. Then, apply enough pressure to snap the tablet segments apart. Do not use the tablet if it does not break on the scored lines.
• You may also take doxycycline by sprinkling the equally broken tablets onto cold, soft food, such as applesauce. This mixture must be swallowed immediately without chewing and followed with a glass of cool water to ensure complete swallowing of the pellets. Do not store the mixture for later use.

Swallow the capsule whole. Do not break, crush, chew, or open it.

Shake the oral liquid well just before each use. Measure the dose with a marked measuring spoon, oral syringe, or medicine cup.

Drink plenty of fluids to avoid throat irritation and ulceration.

If you are using doxycycline to prevent malaria while traveling, start taking the medicine 1 or 2 days before you travel. Take the medicine every day during your trip and continue taking it for 4 weeks after you return. However, do not use the medicine for longer than 4 months.

If you are using Oracea™ delayed-release capsules:

• You should take doxycycline on an empty stomach, preferably at least 1 hour before or 2 hours after meals.
• You should take doxycycline with a full glass of water while sitting or standing.
• To prevent throat irritation, do not lay down right after taking doxycycline.

Use only the brand of doxycycline that your doctor prescribed. Different brands may not work the same way.

To switch from Doryx® delayed-release tablets to Doryx® MPC delayed-release tablets:

• Replace a 50 milligram (mg) dose of Doryx® delayed-release tablet with a 60 mg dose of Doryx® MPC delayed-release tablet.
• Replace a 100 mg dose of Doryx® delayed-release tablet with a 120 mg dose of Doryx® MPC delayed-release tablet.

To help clear up your infection completely, keep taking doxycycline for the full time of treatment, even if you begin to feel better after a few days. If you stop taking doxycycline too soon, your symptoms may return.

Dosing

The dose of doxycycline will be different for different patients. Follow your doctor's orders or the directions on the label. The following information includes only the average doses of doxycycline. If your dose is different, do not change it unless your doctor tells you to do so.

The amount of medicine that you take depends on the strength of the medicine. Also, the number of doses you take each day, the time allowed between doses, and the length of time you take the medicine depend on the medical problem for which you are using the medicine.

• For oral dosage forms (capsules, Doryx® delayed-release tablets, suspension, syrup, tablets):
  • For infections:
    • Adults—100 milligrams (mg) every 12 hours on the first day, then 100 mg once a day or 50 to 100 mg every 12 hours.
    • Children older than 8 years of age and weighs 45 kilograms (kg) or more—100 mg every 12 hours on the first day, then 100 mg once a day or 50 to 100 mg every 12 hours.
    • Children older than 8 years of age and weighs less than 45 kg—Dose is based on body weight and must be determined by your doctor. The dose is usually 4.4 mg per kg of body weight per day and divided into 2 doses on the first day of treatment. This is followed by 2.2 mg per kg of body weight per day, taken as a single dose or divided into two doses on the following days.
    • Children up to 8 years of age—Use is not recommended.
  • For the prevention of malaria:
    • Adults—100 milligrams (mg) once a day. You should take the first dose 1 or 2 days before traveling to an area where malaria may occur, and continue taking the medicine every day throughout your travel and for 4 weeks after you leave the malarious area.
    • Children older than 8 years of age—Dose is based on body weight and must be determined by your doctor. The dose is usually 2 milligrams (mg) per kilogram (kg) of body weight per day, taken as a single dose. You should take the first dose 1 or 2 days before travel to an area where malaria may occur, and continue taking the medicine every day throughout travel and for 4 weeks after you leave the malarious area.
    • Children up to 8 years of age—Use is not recommended.
  • For anthrax after possible exposure:
    • Adults and children weighing 45 kilograms (kg) or more—100 milligrams (mg) two times a day (taken every 12 hours) for 60 days.
    • Children weighing less than 45 kg—Dose is based on body weight and must be determined by your doctor. The dose is usually 2.2 milligrams (mg) per kilogram (kg) of body weight per day, two times a day for 60 days.
• For oral dosage form (delayed-release capsules):
  • For the treatment of pimples from rosacea:
    • Adults—40 milligrams (mg) or one capsule once a day, in the morning.
    • Children—Use and dose must be determined by your doctor.
• For oral dosage form (Doryx® MPC delayed-release tablet):
  • For infections:
    • Adults and children older than 8 years of age and weighs 45 kilograms (kg) or more, with or without severe or life-threatening infections—120 milligrams (mg) every 12 hours on the first day, then 120 mg once a day or 60 to 120 mg every 12 hours.
    • Children older than 8 years of age and weighs less than 45 kg—Dose is based on body weight and must be determined by your doctor. The dose is usually 5.3 mg per kg of body weight per day and divided into 2 doses on the first day of treatment. This is followed by 2.6 mg per kg of body weight per day, taken as a single dose or divided into two doses on the following days.
    • Children weighing less than 45 kg with severe or life-threatening infections—Dose is based on body weight and must be determined by your doctor. The dose is usually 2.6 mg per kg of body weight per day given every 12 hours.
    • Children 8 years of age and younger—Use is not recommended.
  • For prevention of malaria:
    • Adults and children weighing more than 45 kilograms (kg)—120 milligrams (mg) once a day. You should take the first dose 1 or 2 days before traveling to an area where malaria may occur, and continue taking the medicine every day throughout your travel and for 4 weeks after you leave the malarious area.
    • Children 8 years of age and older—Dose is based on body weight and must be determined by your doctor. The dose is usually 2.4 milligrams (mg) per kilogram (kg) of body weight per day, taken as a single dose. You should take the first dose 1 or 2 days before traveling to an area where malaria may occur, and continue taking the medicine every day throughout your travel and for 4 weeks after you leave the malarious area.
    • Children up to 8 years of age—Use is not recommended.
  • For anthrax after possible exposure:
    • Adults and children weighing 45 kilograms (kg) or more—120 milligrams (mg) two times a day for 60 days.
    • Children weighing less than 45 kg—Dose is based on body weight and must be determined by your doctor. The dose is usually 2.6 milligrams (mg) per kilogram (kg) of body weight per day, two times a day for 60 days.

Missed Dose

If you miss a dose of doxycycline, take it as soon as possible. However, if it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not double doses.

Storage

Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light. Keep from freezing.

Keep out of the reach of children.

Do not keep outdated medicine or medicine no longer needed.

Ask your healthcare professional how you should dispose of any medicine you do not use.

Tetracyclines are readily absorbed and are bound to plasma proteins in varying degrees. They are concentrated by the liver in the bile and excreted in the urine and feces at high concentrations in a biologically active form. Doxycycline is virtually completely absorbed after oral administration.

Following a 200 mg dose of Doxycycline monohydrate, 24 normal adult volunteers averaged the following serum concentration values:

Excretion of Doxycycline by the kidney is about 40%/72 hours in individuals with normal function (creatinine clearance about 75 mL/min). This percentage excretion may fall as low as 1 to 5%/72 hours in individuals with severe renal insufficiency (creatinine clearance below 10 mL/min). Studies have shown no significant difference in serum half-life of Doxycycline (range 18 to 22 hours) in individuals with normal and severely impaired renal functioHemodialysis does not alter serum half- life.

Microbiology

Mechanism of Action

Doxycycline inhibits bacterial protein synthesis by binding to the 30S ribosomal subunit. Doxycycline has bacteriostatic activity against a broad range of Gram-positive and Gram-negative bacteria.

Resistance

Cross resistance with other tetracyclines is common.

Antimicrobial Activity

Doxycycline has been shown to be active against most isolates of the following microorganisms, both in vitro and in clinical infections (seeINDICATIONS AND USAGE).

Gram-Negative Bacteria

Acinetobacter species

Bartonella  bacilliformis

Brucella species

Campylobacter fetus

Enterobacter aerogenes

Escherichia coli

Francisella tularensis

Haemophilus ducreyi

Haemophilus influenza

Klebsiella granulomatis

Klebsiella species

Neisseria gonorrhoeae

Shigella  species

Vibrio cholerae

Yersinia  pestis

Gram-Positive Bacteria

Bacillus anthracis

Listeria monocytogenes

Streptococcus pneumoniae

Anaerobic Bacteria

Clostridium species

Fusobacterium fusiforme

Propionibacterium acnes

Other Bacteria

Nocardiae and other Actinomyces species

Borrelia  recurrentis

Chlamydophila psittaci

Chlamydia  trachomatis

Mycoplasma  pneumoniae

Rickettsiae

Treponema  pallidum

Treponema  pallidum subspecies pertenue

Ureaplasma  urealyticum

Parasites

Balantidium coli

Entamoeba species

Susceptibility Testing Methods

When available, the clinical microbiology laboratory should provide cumulative reports of in vitro susceptibility test results for antimicrobial drugs used in local hospitals and practice areas as periodic reports that describe the susceptibility profile of nosocomial and community-acquired pathogens. These reports should aid the physician in selecting the most effective antimicrobial.

DilutionTechniques

Quantitative methods are used to determine antimicrobial minimum inhibitory concentrations (MICs). These MICs provide estimates of the susceptibility of bacteria to antimicrobial compounds. The MICs should be determined using a standardized test method (broth and/or agar).1,2,4,6,7  The MIC values should be interpreted according to criteria provided in Table 1.

Diffusion Techniques

Quantitative methods that require measurement of zone diameters can also provide reproducible estimates of the susceptibility of bacteria to antimicrobial compounds. The zone size should be determined using a standardized test method.1,3,4  This procedure uses paper disks impregnated with 30 mcg Doxycycline to test the susceptibility of microorganisms to Doxycycline. The disk diffusion interpretive criteria are provided in Table 1.

Anaerobic Techniques

For anaerobic bacteria, the susceptibility to Doxycycline can be determined by a standardized test method.1,5The MIC values obtained should be interpreted according to the criteria provided in Table 1

A report of Susceptible (S) indicates that the antimicrobial is likely to inhibit growth of the microorganism if the antimicrobial drug reaches the concentration usually achievable at the site of infection. A report of Intermediate (I) indicates that the result should be considered equivocal, and, if the microorganism is not fully susceptible to alternative, clinically feasible drugs, the test should be repeated. This category implies possible clinical applicability in body sites where the drug product is physiologically concentrated or in situations where high dosage of drug can be used. This category also provides a buffer zone that prevents small uncontrolled technical factors from causing major discrepancies in interpretation. A report of Resistant (R) indicates that the antimicrobial drug is not likely to inhibit growth of the microorganism if the antimicrobial drug reaches the concentrations usually achievable at the infection site; other therapy should be selected.

Quality Control

Standardized susceptibility test procedures require the use of laboratory controls to monitor and ensure the accuracy and precision of the supplies and reagents used in the assay, and the techniques of the individuals performing the test.1,2,3,4,5,6,7Standard Doxycycline and tetracycline powders should provide the following range of MIC values noted in Table 2. For the diffusion technique using the 30 mcg Doxycycline disk or 30 mcg tetracycline disk the criteria noted in should be achieved.

(doks i SYE kleen)

Acne: Adjunctive therapy in severe acne.

Actinomycosis: Treatment of actinomycosis caused by Actinomyces israelii when penicillin is contraindicated.

Acute intestinal amebiasis: Adjunct to amebicides in acute intestinal amebiasis.

Anthrax, including inhalational anthrax (postexposure): Treatment of anthrax caused by Bacillus anthracis, including inhalational (postexposure) prophylaxis; to reduce the incidence or progression of disease following exposure to aerosolized B. anthracis.

Cholera: Treatment of cholera infections caused by Vibrio cholerae.

Clostridium: Treatment of infections caused by Clostridium spp. when penicillin is contraindicated.

Gram-negative infections: Treatment of infections caused by Escherichia coli, Enterobacter aerogenes, Shigella spp., Acinetobacter spp., Klebsiella spp. (respiratory and urinary infections), and Bacteroides spp.; Neisseria meningitidis (when penicillin is contraindicated).

Gram-positive infections: Treatment of infections caused by Streptococcus spp., when susceptible.

Listeriosis: Treatment of listeriosis due to Listeria monocytogenes when penicillin is contraindicated.

Malaria prophylaxis: Prophylaxis of malaria due to Plasmodium falciparum in short-term travelers (under 4 months) to areas with chloroquine and/or pyrimethamine-sulfadoxine-resistant strains.

Mycoplasma pneumoniae: Treatment of infections caused by Mycoplasma pneumoniae.

Ophthalmic infections: Treatment of inclusion conjunctivitis or trachoma caused by Chlamydia trachomatis.

Periodontitis (20 mg tablet and capsule [Periostat (Canadian product)] only): Adjunct to scaling and root planing to promote attachment level gain and to reduce pocket depth in patients with adult periodontitis.

Relapsing fever: Treatment of relapsing fever caused by Borrelia recurrentis.

Respiratory tract infections: Treatment of respiratory infections caused by Haemophilus influenzae, Klebsiella spp., or Mycoplasma pneumoniae; treatment of upper respiratory tract infections caused by Streptococcus pneumoniae; respiratory infections caused by Staphylococcus aureus (doxycycline is not the drug of choice in the treatment of any type of staphylococcal infections).

Rickettsial infections: Treatment of Rocky Mountain spotted fever, typhus fever and the typhus group, Q fever, rickettsialpox, and tick fevers caused by Rickettsiae.

Rosacea (Oracea, Apprilon [Canadian product] only): Treatment of only inflammatory lesions (papules and pustules) of rosacea in adults.

Sexually transmitted diseases: Treatment of lymphogranuloma venereum and uncomplicated urethral, endocervical, or rectal infections caused by Chlamydia trachomatis; granuloma inguinale (donovanosis) caused by Klebsiella granulomatis; chancroid caused by Haemophilus ducreyi; nongonococcal urethritis caused by Ureaplasma urealyticum; when penicillin is contraindicated, uncomplicated gonorrhea caused by Neisseria gonorrhea and syphilis caused by Treponema pallidum.

Note: The Centers for Disease Control and Prevention (CDC) sexually transmitted disease guidelines recommend dual antimicrobial therapy be used for uncomplicated gonorrhea due to N. gonorrhea resistance concerns; ceftriaxone is the preferred cephalosporin and doxycycline is an alternate option for the second antimicrobial only in cases azithromycin allergy (CDC [Workowski 2015]).

Skin and skin structure infections (Avidoxy only): Treatment of skin and skin structure infections caused by Staphylococcus aureus (doxycycline is not the drug of choice in the treatment of any type of staphylococcal infections).

Vincent infection: Treatment of Vincent infection caused by Fusobacterium fusiforme when penicillin is contraindicated.

Yaws: Treatment of yaws caused by Treponema pallidum subspecies pertenue when penicillin is contraindicated.

Zoonotic infections: Treatment of psittacosis (ornithosis) caused by Chlamydophila psittaci; plague due to Yersinia pestis; tularemia caused by Francisella tularensis; brucellosis caused by Brucella spp. (in conjunction with streptomycin); bartonellosis caused by Bartonella bacilliformis; infections caused by Campylobacter fetus.

Acute bacterial rhinosinusitis (ABRS)

Based on the Infectious Diseases Society of America (IDSA) guidelines for acute bacterial rhinosinusitis (ABRS) in children and adults, doxycycline is effective and recommended for the treatment of ABRS in adults. Doxycycline is not suitable for use in children.

Anaplasmosis

Based on the IDSA guidelines for the clinical assessment, treatment, and prevention of Lyme disease, human granulocytic anaplasmosis (HGA) and babesiosis and the Centers for Disease Control and Prevention (CDC) guideline for the Diagnosis and Management of Tickborne Rickettsial Diseases: Rocky Mountain Spotted Fever and Other Spotted Fever Group Rickettsioses, Ehrlichioses, and Anaplasmosis, doxycycline is effective and recommended for the treatment of human anaplasmosis (also known as human granulocytic anaplasmosis [HGA]).

Bacillary angiomatosis (cutaneous)

Based on the Infectious Diseases Society of America (IDSA) guidelines for the diagnosis and management of skin and soft tissue infections (SSTI), doxycycline may be considered for the treatment of cutaneous bacillary angiomatosis. Guidelines state that therapy has not been systematically examined and doxycycline appears effective based on case reports and small series.

Bartonella infections in HIV-infected patients (adolescents and adults)

Based on the US Department of Health and Human Services (HHS) Guidelines for Prevention and Treatment of Opportunistic Infections in HIV-Infected Adults and Adolescents, doxycycline is a recommended and effective agent for treatment of bacillary angiomatosis, peliosis hepatis, bacteremia, osteomyelitis, CNS infections, infective endocarditis, and other severe infections due to Bartonella in adolescent and adult HIV-infected patients.

Bite wounds (animal/human)

Based on the Infectious Diseases Society of America (IDSA) guidelines for the diagnosis and management of skin and soft tissue infections (SSTI), doxycycline is an acceptable alternative agent for the treatment of bite wounds (animal or human).

Cervicitis due to Chlamydia trachomatis

Based on the Centers for Disease Control and Prevention (CDC) sexually transmitted diseases treatment guidelines, doxycycline (with or without additional therapy for gonococcal disease) is an effective and recommended alternative agent in the treatment of cervicitis due to Chlamydia trachomatis.

Community-acquired pneumonia (children)

Following clinical guideline recommendations on the management of CAP reduces the incidence of morbidity and mortality related to pneumonia. For children older than 7 years suspected or known to have atypical CAP, doxycycline is an acceptable alternative to macrolide therapy in outpatient and inpatient settings.

Ehrlichiosis

Based on the Centers for Disease Control and Prevention (CDC) guideline for the Diagnosis and Management of Tickborne Rickettsial Diseases: Rocky Mountain Spotted Fever and Other Spotted Fever Group Rickettsioses, Ehrlichioses, and Anaplasmosis, doxycycline is effective and recommended for the treatment of human ehrlichiosis.

Epididymitis

Based on the Centers for Disease Control and Prevention (CDC) sexually transmitted diseases treatment guidelines, doxycycline in combination with ceftriaxone is an effective and recommended agent in the treatment acute epididymitis likely caused by sexually-transmitted chlamydia and gonorrhea.

Gonococcal (uncomplicated) infection of the rectum (adults)

Based on the Centers for Disease Control and Prevention (CDC) sexually transmitted diseases treatment guidelines, doxycycline is a recommended alternative agent to azithromycin only in azithromycin allergic patients when combined with ceftriaxone in the treatment of uncomplicated gonococcal infections of the rectum. Azithromycin is preferred over doxycycline as the second antimicrobial in combination with ceftriaxone (or cefixime) due to the prevalence of tetracycline resistance.

Infective Endocarditis (Bartonella) (Adults)

According to AHA guidelines, doxycycline is preferred in combination with gentamicin or rifampin for the treatment of confirmed Bartonella endocarditis.

Lyme disease

Controlled trials support the use of doxycycline in the prevention of development of Lyme disease when administered within 72 hours of the Ixodes scapularis tick bite and also in the management of multiple manifestations of Lyme disease.

Guidelines from the Infectious Diseases Society of America (IDSA) and American Academy of Neurology (AAN) recommend the use of oral doxycycline as an effective treatment for multiple manifestations of Lyme disease, including more severe neurological manifestations and late Lyme arthritis.

Malaria, treatment

Based on the Centers for Disease Control and Prevention (CDC) guidelines for the treatment of malaria in the United States, doxycycline, is an effective and recommended treatment option for uncomplicated Plasmodium falciparum or unidentified species in areas with chloroquine-resistance or unknown resistance (in combination with quinine sulfate); Plasmodium vivax in chloroquine-resistant areas (in combination with quinine sulfate and primaquine); and severe malaria (in combination with quinidine gluconate).

Pelvic inflammatory disease

Based on the Centers for Disease Control and Prevention (CDC) sexually transmitted diseases treatment guidelines, doxycycline in combination with cefotetan or cefoxitin is an effective and recommended parenteral regimen in the treatment of pelvic inflammatory disease.

Proctitis, proctocolitis, enteritis

Based on the Centers for Disease Control and Prevention (CDC) sexually transmitted diseases treatment guidelines, doxycycline in combination with ceftriaxone is an effective and recommended in the treatment of proctitis, proctocolitis, or enteritis.

Prosthetic joint infection

Based on the Infectious Diseases Society of America (IDSA) guidelines for the management of prosthetic joint infection, doxycycline is an effective and recommended agent for treatment (oral phase) of prosthetic joint infection and for chronic oral antimicrobial suppression of prosthetic joint infection.

Skin and soft tissue infections due to MSSA or MRSA

Based on the Infectious Diseases Society of America (IDSA) guidelines for the diagnosis and management of skin and soft tissue infections (SSTI) and the treatment of methicillin-resistant Staphylococcus aureus (MRSA) infections in adults and children, doxycycline is an effective and recommended treatment option for skin and soft tissue infections caused by methicillin-sensitive S. aureus (MSSA) and methicillin-resistant S. aureus (MRSA), particularly purulent cellulitis due to community-acquired MRSA (CA-MRSA).

Skin and soft tissue necrotizing infections due to Aeromonas hydrophila or Vibrio vulnificus

Based on the Infectious Diseases Society of America (IDSA) guidelines for the diagnosis and management of skin and soft tissue infections (SSTI), doxycycline is an effective and recommended treatment for necrotizing infections of the skin, fascia, and muscle caused by Aeromonas hydrophila (in combination with ciprofloxacin or ceftriaxone) or Vibrio vulnificus (in combination with ceftriaxone or cefotaxime).

Tularemia (when used as a biological weapon)

Based on consensus based recommendations created by the Working Group on Civilian Biodefense, oral doxycycline (or oral ciprofloxacin) is considered a drug of choice in the setting of mass casualty management and postexposure prophylaxis. In the setting of contained casualty, doxycycline IV is considered an alternative agent [Dennis 2001].

Additional Off-Label Uses

Localized juvenile periodontitis (LJP); Periodontitis (refractory); Sclerosing agent for pleural effusion (injection)

Note: Doryx MPC 120 mg is equivalent to Doryx (doxycycline hyclate delayed-release tablets) 100 mg

Acute bacterial rhinosinusitis (off-label use): Oral: 200 mg/day in 1 to 2 divided doses for 5 to 7 days (Chow 2012)

Anaplasmosis (off-label use): Oral, IV: 100 mg twice daily for 10 days to provide appropriate length of therapy for possible co-infection with Lyme disease or, alternatively, add another antimicrobial with efficacy against Borrelia burgdorferi (IDSA [Wormser 2006]; CDC [Biggs 2016])

Anthrax:

Inhalational (postexposure prophylaxis): Oral (immediate and delayed release), IV (use oral route when possible): 100 mg every 12 hours for 60 days (CDC [Hendricks 2014])

Doryx MPC: Oral: 120 mg every 12 hours for 60 days

Cutaneous (without systemic involvement), treatment: Oral: 100 mg every 12 hours for 7 to 10 days after naturally acquired infection; 60 days for bioterrorism-related cases (CDC [Hendricks 2014].

Systemic (penicillin susceptible strains; excluding meningitis), treatment: IV: Initial: 200 mg as a single dose, then 100 mg every 12 hours in combination with penicillin G or ampicillin; duration of therapy is 2 weeks or until clinically stable. Patients exposed to aerosolized spores require prophylaxis to complete an antimicrobial course of 60 days from illness onset (CDC [Hendricks 2014])

Bacillary angiomatosis, cutaneous (off-label use): Oral: 100 mg twice daily. Note: Duration of initial therapy should be for 2 weeks to 2 months, although treatment durations are not standardized (IDSA [Stevens 2014])

Bartonella infection in HIV-infected patients (off-label use) (HHS [OI adult 2015]): Note: Duration of therapy is at least 3 months; continuation of therapy depends on relapse occurrence and clinical condition

Bacillary Angiomatosis, Peliosis Hepatis, Bacteremia, and Osteomyelitis: Oral, IV: 100 mg every 12 hours

Infections Involving the CNS: Oral, IV: 100 mg every 12 hours; may add rifampin therapy

Confirmed Bartonella Endocarditis: 100 mg IV every 12 hours in combination with gentamicin for 2 weeks, then continue with doxycycline 100 mg IV or orally every 12 hours

Other Severe Infections: Oral, IV: 100 mg every 12 hours in combination with rifampin

Bite wounds (animal/human) (off-label use) (IDSA [Stevens 2014]):

Animal bite: Oral, IV: 100 mg twice daily

Human bite: Oral: 100 mg twice daily

Brucellosis: Oral: 100 mg twice daily for 6 weeks with rifampin or streptomycin (Ariza 2007). Note: In the treatment of brucellar native vertebral osteomyelitis, 3 months of doxycycline therapy is recommended (usually with 2 to 3 weeks of concomitant streptomycin or 3 months of concomitant rifampin) (IDSA [Berbari 2015]).

Cellulitis (purulent) due to community-acquired MRSA (off-label use): Oral: 100 mg twice daily for 5 to 10 days (Liu 2011)

Cervicitis due to Chlamydia trachomatis (off-label use): Oral: 100 mg twice daily for 7 days; consider concurrent treatment for gonorrhea if patient at risk for contracting or lives in an area with high prevalence of gonorrhea (CDC [Workowski 2015])

Chlamydia trachomatis, uncomplicated urethral, endocervical or rectal infections: Oral: (immediate and delayed release): 100 mg twice daily for 7 days; alternatively, for endocervical or urethral infections, may give 200 mg delayed-release tablet once daily for 7 days (CDC [Workowski 2015])

Doryx MPC: Oral: 120 mg twice daily for 7 days

Community-acquired pneumonia, bronchitis: Oral, IV: 100 mg twice daily (Ailani 1999; Mandell 2007)

Ehrlichiosis (off-label use): Oral, IV: 100 mg twice daily; treat for at least 3 days after fever subsides and clinical improvement is noted (typical minimum duration of therapy is 5 to 7 days; severe or complicated disease may require longer treatment) (CDC [Biggs 2016])

Epididymitis (most likely caused by C. trachomatis or N. gonorrhoeae) (off-label use): Oral (immediate and delayed release): 100 mg twice daily for 10 days (in combination with ceftriaxone); sexual partners should also be referred for treatment (CDC [Workowski 2015])

Doryx MPC: Oral: 120 mg twice daily for at least 10 days

Gonococcal (uncomplicated) infection of the cervix, rectum (off-label use) or urethra: Oral: (immediate and delayed release): 100 mg twice daily for 7 days; must be given in combination with ceftriaxone (preferred) or cefixime (only if ceftriaxone is not available) (CDC [Workowski 2015]). Note: Azithromycin is preferred over doxycycline as the second antimicrobial in combination with ceftriaxone in uncomplicated infections due to a high prevalence of tetracycline resistance in isolates and the convenience/compliance advantages of single dose azithromycin therapy; doxycycline should only be used in cases of azithromycin allergy (CDC [Workowski 2015]).

Alternatively, manufacturer's labeling recommends a single-visit dose in nonanorectal infections in men: 300 mg initially, repeat dose in 1 hour (total dose: 600 mg); of note, this dosing is not mentioned in the CDC STD 2015 treatment guidelines.

Doryx MPC: Oral: 120 mg twice daily for 7 days. Note: Not for anorectal infections in men

Alternatively, manufacturer's labeling recommends a single-visit dose: 360 mg initially, repeat dose in 1 hour (total dose: 720 mg); of note, this dosing is not mentioned in the CDC STD 2015 treatment guidelines.

Granuloma inguinale (donovanosis) (alternative to preferred therapy): Oral: 100 mg twice daily for at least 3 weeks (and until lesions have healed) (CDC [Workowski 2015]). Note: If symptoms do not improve within the first few days of therapy, the addition of gentamicin may be considered (CDC [Workowski 2015]).

Lyme disease (off-label use): Oral (Halperin 2007; IDSA [Wormser 2006]):

Prevention: Initiate within 72 hours of tick removal: 200 mg administered as a single dose

Treatment (early Lyme disease without neurologic manifestations): 100 mg twice daily for 10 to 21 days

Treatment (meningitis or other early neurologic manifestations): 100 to 200 mg twice daily for 14 days (range: 10 to 28 days)

Lymphogranuloma venereum: Oral: 100 mg twice daily for 21 days (CDC [Workowski 2015])

Malaria chemoprophylaxis: Start 1 to 2 days prior to travel to endemic area; continue daily during travel and for 4 weeks after leaving endemic area

Oral (immediate and delayed release): 100 mg/day

Doryx MPC: Oral: 120 mg daily

Malaria, severe, treatment (off-label use): Oral, IV: 100 mg every 12 hours for 7 days with quinidine gluconate. Note: Quinidine gluconate duration is region specific; consult CDC for current recommendations (CDC 2013).

Malaria, uncomplicated, treatment (off-label use): Oral: 100 mg twice daily for 7 days with quinine sulfate (and primaquine for Plasmodium vivax). Note: Quinine sulfate duration is region specific; consult CDC for current recommendations (CDC 2013).

Nongonococcal urethritis: Oral (immediate and delayed release): 100 mg twice daily for 7 days

Doryx MPC: Oral: 120 mg twice daily for 7 days

Pelvic inflammatory disease (off-label use):

Treatment, inpatient: IV: 100 mg twice daily (in combination with cefoxitin [preferred] or cefotetan [preferred] or ampicillin/sulbactam [alternative]); transition from parenteral to oral doxycycline therapy can usually be initiated within 24 to 48 hours of clinical improvement for a total treatment duration of 14 days. If tubo-ovarian abscess is present, oral clindamycin or oral metronidazole in combination with doxycycline is preferred to complete 14 days of therapy (CDC [Workowski 2015])

Treatment, outpatient: Oral: 100 mg twice daily for 14 days (with or without metronidazole); must be preceded by a single IM dose of cefoxitin (plus oral probenecid) or ceftriaxone or other parenteral third-generation cephalosporin (eg, cefotaxime) (CDC [Workowski 2015])

Periodontitis: Oral: 20 mg twice daily as an adjunct following scaling and root planing; may treat for up to 9 months

Periodontitis, refractory (off-label use): Oral: 100 to 200 mg daily (Jolkovsky 2006)

Proctitis, proctocolitis, enteritis (off-label use): Oral: 100 mg twice daily for 7 days (in combination with ceftriaxone) (CDC [Workowski 2015]). Note: Consider 21 days of treatment for presumptive lymphogranuloma venereum in those with HIV infection or positive rectal chlamydial amplification test (NAAT).

Prosthetic joint infection (off-label use): Oral:

Chronic oral antimicrobial suppression:

Cutibacterium spp (alternative to penicillin or amoxicillin): 100 mg twice daily (Osmon 2013)

Staphylococci (oxacillin-resistant): 100 mg twice daily (Osmon 2013)

Staphylococci (oxacillin-sensitive or –resistant) oral phase treatment (after completion of pathogen-specific IV) following 1-stage exchange:

Total ankle, elbow, hip, or shoulder arthroplasty: 100 mg twice daily for 3 months; Note: Must be used in combination with rifampin (Osmon 2013)

Total knee arthroplasty: 100 mg twice daily for 6 months; Note: Must be used in combination with rifampin (Osmon 2013)

Q fever: Oral:

Acute: 100 mg every 12 hours for 14 days (CDC 2013); Note: In patients who have valvular heart disease, consider increasing the duration of therapy to 1 year and adding hydroxychloroquine to the regimen to prevent endocarditis; consultation with an infectious disease expert is recommended (CDC 2002; Fenollar 2001).

Chronic (CDC 2013):

Endocarditis or vascular infection: 100 mg every 12 hours in combination with hydroxychloroquine for ≥18 months

Noncardiac organ disease: 100 mg every 12 hours in combination with hydroxychloroquine (duration based on serologic response; ID consult recommended)

Postpartum with serologic evidence present >12 months after delivery: 100 mg every 12 hours in combination with hydroxychloroquine for 12 months

Rosacea: Oral: Oracea, Apprilon [Canadian product]: 40 mg once daily in the morning

Sclerosing agent for pleural effusion (off-label use): Intrapleural: 500 mg as a single dose in 100 mL NS (Porcel 2006); may require a repeat dose (Kvale 2007)

Skin and soft tissue infections (off-label use) (IDSA [Stevens 2014]):

Due to MSSA or MRSA: Oral: 100 mg twice daily

Necrotizing infection due to Aeromonas hydrophila or Vibrio vulnificus: IV: 100 mg every 12 hours; in combination with ciprofloxacin or ceftriaxone for Aeromonas hydrophila or in combination with ceftriaxone or cefotaxime for Vibrio vulnificus. Continue treatment until further debridement is not necessary, patient has clinically improved, and patient is afebrile for 48 to 72 hours.

Syphilis, penicillin-allergic patients: Note: Data to support the use of alternatives to pencillin are limited in primary and secondary syphilis and are not well documented in the treatment of latent syphilis (CDC [Workowski 2015]).

Primary/secondary: Oral (immediate and delayed release): 100 mg twice daily for 14 days

Doryx MPC: Oral: 120 mg twice daily for 14 days

Latent: Oral (immediate and delayed release): 100 mg twice daily for 28 days

Doryx MPC: Oral: 120 mg twice daily for 28 days

Tickborne rickettsial disease (eg, Rocky Mountain spotted fever): Oral, IV: 100 mg twice daily; treat for at least 3 days after fever subsides and clinical improvement is noted (typical minimum duration of therapy is 5 to 7 days; severe or complicated disease may require longer treatment) (CDC [Biggs 2016])

Tularemia:

Mild to moderate infections: Oral: 100 mg twice daily for ≥14 days (IDSA [Stevens 2014])

Mass casualty management or postexposure prophylaxis (when used as a biological weapon): Oral: 100 mg twice daily for 14 days (Dennis 2001)

Contained casualty management (when used as a biological weapon): IV (may transition to oral if clinically appropriate): 100 mg every 12 hours for 14 to 21 days (Dennis 2001)

Vibrio cholerae: Oral: 300 mg as a single dose (WHO 2004)

Yersinia pestis (plague): Oral, IV: 200 mg initially then 100 mg twice daily or 200 mg once daily for 10 to 14 days, or until 2 days after fever subsides (CDC 2015; Daya 2005; Inglesby 2000; IDSA [Stevens 2014])

Usual dosage range:

Immediate and delayed-release:

Children >8 years and Adolescents (<45 kg): Oral, IV: 2 to 4 mg/kg/day in 1 to 2 divided doses, not to exceed 200 mg/day (AAP [Red Book] 2015)

Children >8 years and Adolescents (≥45 kg): Oral, IV: Refer to adult dosing.

Doryx MPC: Oral:

Mild-to-moderate infections:

Children >8 years and Adolescents (<45 kg): 5.3 mg/kg/day in 2 divided doses on day 1, followed by 2.6 mg/kg/day in 1 to 2 divided doses

Children >8 years and Adolescents (≥45 kg): Refer to adult dosing.

Severe or life-threatening infections (eg, anthrax, tickborne rickettsial disease):

Children >8 years and Adolescents (<45 kg): 2.6 mg/kg/dose every 12 hours

Children >8 years and Adolescents (≥45 kg): Refer to adult dosing.

Anaplasmosis (off-label use):

Children <8 years: Oral, IV:

<45 kg: 2.2 mg/kg/dose (maximum dose: 100 mg/dose) every 12 hours

Duration of therapy:

If co-infection with Lyme disease is suspected, treat for 10 days or, alternatively, add another antimicrobial with efficacy against Borrelia burgdorferi (CDC [Biggs 2016])

If co-infection with Lyme disease is not suspected, may treat for at least 3 days after fever subsides and clinical improvement is noted; typical minimum duration of therapy is 5 to 7 days (CDC [Biggs 2016])

Children ≥8 years and Adolescents: Oral, IV:

<45 kg: 2.2 mg/kg/dose (maximum dose: 100 mg/dose) every 12 hours

Duration of therapy: 10 days to provide appropriate length of therapy for possible co-infection with Lyme disease or, alternatively, add another antimicrobial with efficacy against Borrelia burgdorferi (CDC [Biggs 2016]; IDSA [Wormser 2006])

≥45 kg: Refer to adult dosing.

Anthrax:

Inhalational (postexposure prophylaxis) (ACIP 2010): Oral (immediate and delayed-release), IV (use oral route when possible):

≤8 years: 2.2 mg/kg every 12 hours for 60 days

>8 years and ≤45 kg: 2.2 mg/kg every 12 hours for 60 days

>8 years and >45 kg: 100 mg every 12 hours for 60 days

Doryx MPC: Oral:

Children >8 years and Adolescents (<45 kg): 2.6 mg/kg/dose twice daily for 60 days

Children >8 years and Adolescents (≥45 kg): Refer to adult dosing.

Cutaneous (treatment): Oral: See dosing for “Inhalational (postexposure prophylaxis)”

Note: In the presence of systemic involvement, extensive edema, and/or lesions on head/neck, doxycycline should initially be administered IV

Inhalational/gastrointestinal/oropharyngeal (treatment): IV: Refer to dosing for inhalational anthrax (postexposure prophylaxis); switch to oral therapy when clinically appropriate.

Note: Initial treatment should include two or more agents predicted to be effective (CDC 2001). Agents suggested for use in conjunction with doxycycline or ciprofloxacin include rifampin, vancomycin, imipenem, penicillin, ampicillin, chloramphenicol, clindamycin, and clarithromycin. May switch to oral antimicrobial therapy when clinically appropriate. Continue combined therapy for 60 days

Bartonella infection in HIV-infected patients (off-label use): Refer to adult dosing.

Community-acquired pneumonia (CAP) (IDSA/PIDS 2011): Children >7 years: Oral: Note: A beta-lactam antibiotic should be added if typical bacterial pneumonia cannot be ruled out.

Presumed atypical, mild atypical (M. pneumoniae, C. pneumoniae, C. trachomatis) infection or step-down therapy (alternative to azithromycin): 2 to 4 mg/kg/day in 2 divided doses (maximum: 200 mg/day)

Cellulitis (purulent) due to community-acquired MRSA (off-label use): Children >8 years and ≤45 kg: Oral: 2 mg/kg/dose every 12 hours for 5 to 10 days; >45 kg: Refer to adult dosing (Liu 2011)

Chlamydial infections, uncomplicated: Children ≥8 years (and >45 kg) and Adolescents: Oral: US labeling: 100 mg twice daily for 7 days; alternatively, for endocervical or urethral infections, may give 200 mg delayed-release tablet once daily for 7 days (CDC [Workowski 2015])

Ehrlichiosis (off-label use; CDC [Biggs 2016]): Children and Adolescents: Oral, IV:

<45 kg: 2.2 mg/kg/dose (maximum dose: 100 mg/dose) every 12 hours; treat for at least 3 days after fever subsides and clinical improvement is noted (typical minimum duration of therapy is 5 to 7 days; severe or complicated disease may require longer treatment)

≥45 kg: Refer to adult dosing.

Localized juvenile periodontitis (LJP) (off-label use): Oral: 50 to 100 mg/day

Lyme disease (off-label use): Children ≥8 years: Oral (Halperin 2007; Wormser 2006):

Prevention: 4 mg/kg (maximum: 200 mg) administered as a single dose; Note: Initiate within 72 hours of tick removal

Treatment (early Lyme disease without neurologic manifestations): 1 to 2 mg/kg twice daily for 10 to 21 days (maximum: 100 mg/dose)

Treatment (meningitis and other early neurologic manifestations): 4 to 8 mg/kg/day in 2 divided doses for 10 to 28 days (maximum: 200 mg/dose)

Malaria chemoprophylaxis: Start 1 to 2 days prior to travel to endemic area; continue daily during travel and for 4 weeks after leaving endemic area

Children ≥8 years and Adolescents: Oral (immediate and delayed-release):

Manufacturer's labeling:

<45 kg: 2 mg/kg/dose once daily (maximum: 100 mg/day)

≥45 kg: 100 mg once daily

Alternative recommendation: 2.2 mg/kg/dose once daily (maximum: 100 mg/day) (Arguin [CDC 2016]).

Doryx MPC: Oral:

Children >8 years and Adolescents (<45 kg): 2.4 mg/kg/dose once daily

Children >8 years and Adolescents (≥45 kg): Refer to adult dosing.

Malaria, severe, treatment (off-label use): Children ≥8 years: Oral, IV:

<45 kg: 2.2 mg/kg (maximum dose: 100 mg) every 12 hours for 7 days with quinidine gluconate. Note: Quinidine gluconate duration is region specific; consult CDC for current recommendations (CDC 2011).

≥45 kg: 100 mg every 12 hours for 7 days with quinidine gluconate. Note: Quinidine gluconate duration is region specific; consult CDC for current recommendations (CDC 2011).

Malaria, uncomplicated, treatment (off-label use): Children ≥8 years: Oral: 2.2 mg/kg (maximum dose: 100 mg) every 12 hours for 7 days with quinine sulfate. Note: Quinine sulfate duration is region specific, consult CDC for current recommendations (CDC 2011).

Q fever: Oral:

Acute:

Children <8 years with high-risk criteria (eg, hospitalized or have severe illness, with preexisting heart valvulopathy, immunocompromised, or with delayed Q fever diagnosis who have experienced illness for >14 days without resolution of symptoms): 2.2 mg/kg/dose (maximum: 100 mg per dose) twice daily for 14 days (CDC 2013).

Children <8 years with mild or uncomplicated illness: 2.2 mg/kg/dose (maximum: 100 mg per dose) twice daily for 5 days. If patient remains febrile past 5 days of treatment, switch to sulfamethoxazole and trimethoprim (CDC 2013). Note: Some clinicians may recommend initial treatment with sulfamethoxazole and trimethoprim for children <8 years with mild or uncomplicated illness (Hartzell 2008; CDC 2013).

Children ≥8 years and Adolescents: 2.2 mg/kg/dose (maximum: 100 mg per dose) twice daily for 14 days (CDC 2013).

Chronic: ID consult recommended for treatment of chronic Q fever (CDC 2013)

Skin and soft tissue infections due to MSSA or MRSA (off-label use): Children ≥ 8 years: Oral:

≤45 kg: 2 mg/kg every 12 hours (IDSA [Lui 2011])

>45 kg: 100 mg twice daily (IDSA [Lui 2011]; IDSA [Stevens 2014])

Tickborne rickettsial disease (eg, Rocky Mountain spotted fever): Children and Adolescents: Oral, IV:

<45 kg: 2.2 mg/kg/dose (maximum dose: 100 mg) every 12 hours; continue treatment for at least 3 days after fever subsides and clinical improvement is noted (typical minimum duration of therapy is 5 to 7 days; severe or complicated disease may require longer treatment) (CDC [Biggs 2016])

≥45 kg: Refer to adult dosing.

Tularemia (when used as a biological weapon) (off-label use) (Dennis 2001):

Mass casualty management or postexposure prophylaxis: Oral:

Children <45 kg: 2.2 mg/kg twice daily for 14 days

Children ≥45 kg: 100 mg twice daily for 14 days

Contained casualty management: IV (may transition to oral if clinically indicated):

Children <45 kg: 2.2 mg/kg twice daily for 14 to 21 days

Children ≥45 kg: 100 mg every 12 hours for 14 to 21 days

Tetracyclines (in general): Take with food if gastric irritation occurs. While administration with food may decrease GI absorption of doxycycline by up to 20%, administration on an empty stomach is not recommended due to GI intolerance. Of currently available tetracyclines, doxycycline has the least affinity for calcium.

Doxycycline 20 mg tablet, Oracea, Apprilon [Canadian product]: Take on an empty stomach 1 hour before or 2 hours after meals.

Periostat [Canadian product]: Take at least 1 hour before morning and evening meals.

Some products may contain sodium.

CBC, renal and liver function tests periodically with prolonged therapy. When used as part of alternative treatment for gonococcal infection, test of cure 7 days after dose (CDC [Workowski 2015]).

Patients with no risk factors for chronic Q fever should undergo clinical and serological evaluation 6 months after diagnosis of acute Q fever to identify possible progression to chronic disease. Postpartum women treated during pregnancy for acute Q fever, others who are at high risk for progression to chronic disease or when used as part of treatment for chronic Q fever infection unrelated to endocarditis or vascular infection (eg, osteoarticular infections or chronic hepatitis), assess serologic response at 3, 6, 12, 18, and 24 months after diagnosis of acute Q fever (or after delivery in pregnant women) (CDC 2013).

Take the medicine as soon as you can, but skip the missed dose if it is almost time for your next dose. Do not take two doses at one time.

Sometimes it is not safe to use certain medications at the same time. Some drugs can affect your blood levels of other drugs you take, which may increase side effects or make the medications less effective.

Other drugs may affect doxycycline, including prescription and over-the-counter medicines, vitamins, and herbal products. Tell your doctor about all your current medicines and any medicine you start or stop using.