Sildenafil

Before taking sildenafil,

• tell your doctor and pharmacist if you are allergic to sildenafil, any other medications, or any of the ingredients in sildenafil products. Ask your pharmacist for a list of the ingredients.
• do not take sildenafil if you are taking or have recently taken riociguat (Adempas) or nitrates (medications for chest pain) such as isosorbide dinitrate (Isordil), isosorbide mononitrate (Monoket), and nitroglycerin (Minitran, Nitro-Dur, Nitromist, Nitrostat, others). Nitrates come as tablets, sublingual (under the tongue) tablets, sprays, patches, pastes, and ointments. Ask your doctor if you are not sure whether any of your medications contain nitrates.
• do not take street drugs containing nitrates such as amyl nitrate and butyl nitrate ('poppers') while taking sildenafil.
• tell your doctor and pharmacist what prescription and nonprescription medications, vitamins, and nutritional supplements you are taking or plan to take. Be sure to mention any of the following: alpha blockers such as alfuzosin (Uroxatral), doxazosin (Cardura), prazosin (Minipress), tamsulosin (Flomax, in Jalyn), and terazosin; amlodipine (Norvasc, in Amturnide, in Tekamlo); certain antifungals such as itraconazole (Onmel, Sporanox) and ketoconazole (Nizoral); anticoagulants ('blood thinners') such as warfarin (Coumadin, Jantoven); certain barbiturates such as butalbital (in Butapap, in Fioricet, in Fiorinal, others) and secobarbital (Seconal); beta blockers such as atenolol (Tenormin, in Tenoretic), labetalol (Trandate), metoprolol (Lopressor, Toprol XL, in Dutoprol), nadolol (Corgard, in Corzide), and propranolol (Hemangeol, Inderal LA, InnoPran); bosentan (Tracleer); cimetidine ; efavirenz (Sustiva, in Atripla); erythromycin (E.E.S., E-Mycin, Erythrocin); HIV protease inhibitors including amprenavir (Agenerase; no longer available in the U.S.), atazanavir (Reyataz, in Evotaz), darunavir (Prezista, in Prezcobix), fosamprenavir (Lexiva), indinavir (Crixivan), lopinavir (in Kaletra), nelfinavir (Viracept), ritonavir (Norvir, in Kaletra), saquinavir (Invirase), and tipranavir (Aptivus); nevirapine (Viramune); other medications or devices to treat erectile dysfunction; medications for high blood pressure; certain medications for seizures including carbamazepine (Carbatrol, Epitol, Tegretol, others), phenobarbital, and phenytoin (Dilantin, Phenytek); rifabutin (Mycobutin); and rifampin (Rifadin, Rimactane, in Rifamate, in Rifater). Your doctor may need to change the doses of your medications or monitor you carefully for side effects. Many other medications may also interact with sildenafil, so be sure to tell your doctor about all the medications you are taking, even those that do not appear on this list.
• tell your doctor what herbal products you are taking or plan to take, especially St. John's wort.
• tell your doctor if you smoke, if you have ever had an erection that lasted for several hours, and if you have recently lost a large amount of body fluids (dehydration). This can happen if you are sick with fever, diarrhea, or vomiting; sweat a lot; or do not drink enough liquids. Also tell your doctor if you have or have ever had pulmonary veno-occlusive disease (PVOD; blockage of veins in the lungs); a stomach ulcer; heart, kidney, or liver disease; a heart attack; an irregular heartbeat; a stroke; chest pain; high or low blood pressure; high cholesterol; a bleeding disorder; blood circulation problems;blood cell problems such as sickle cell anemia (a disease of the red blood cells), multiple myeloma (cancer of the plasma cells), or leukemia (cancer of the white blood cells); conditions affecting the shape of the penis (e.g., angulation, cavernosal fibrosis, or Peyronie's disease); or diabetes. Also tell your doctor if you or any of your family members have or have ever had an eye disease such as retinitis pigmentosa (an inherited eye condition that causes loss of vision) or if you have ever had sudden severe vision loss, especially if you were told that the vision loss was caused by a blockage of blood flow to the nerves that help you see.
• if you are a woman and you are taking sildenafil to treat PAH, tell your doctor if you are pregnant, plan to become pregnant, or are breastfeeding. If you become pregnant while taking sildenafil, call your doctor.
• if you are having surgery, including dental surgery, tell your doctor or dentist that you are taking sildenafil.
• if you are taking sildenafil to treat erectile dysfunction, tell your doctor if you have ever been advised by a healthcare professional to avoid sexual activity for medical reasons or if you have ever experienced chest pain during sexual activity. Sexual activity may be a strain on your heart, especially if you have heart disease. If you experience chest pain, dizziness, or nausea during sexual activity, call your doctor immediately and avoid sexual activity until your doctor tells you otherwise.
• tell all your healthcare providers that you are taking sildenafil. If you ever need emergency medical treatment for a heart problem, the healthcare providers who treat you will need to know when you last took sildenafil.

If you are taking sildenafil for erectile dysfunction, you are unlikely to miss a dose since this medication is taken as needed, not on a regular dosing schedule.

If you are taking sildenafil for PAH, take the missed dose as soon as you remember it. However, if it is almost time for the next dose, skip the missed dose and continue your regular dosing schedule. Do not take a double dose to make up for a missed one.

Keep all appointments with your doctor.

Do not let anyone else take your medication. Ask your pharmacist any questions you have about refilling your prescription.

It is important for you to keep a written list of all of the prescription and nonprescription (over-the-counter) medicines you are taking, as well as any products such as vitamins, minerals, or other dietary supplements. You should bring this list with you each time you visit a doctor or if you are admitted to a hospital. It is also important information to carry with you in case of emergencies.

• Revatio^®
• Viagra^®

Although extensive testing in animals has demonstrated no negative effects on the fetus, Viagra has not been studied in pregnant women. There is no effect on sperm count or motility of sperm in men.

It is not known whether sildenafil is excreted into breast milk.

Common Side Effects of Viagra

• Headache
• Flushing in the face, neck, or chest
• Upset stomach, indigestion
• Abnormal vision
• Nasal congestion
• Back pain
• Muscular pain or tenderness
• Nausea
• Dizziness
• Rash
• Diarrhea

Serious Side Effects of Viagra

• Change or loss of vision
• Ringing in ears or hearing loss
• Chest pain or irregular heartbeat
• Shortness of breath
• Lightheadedness
• Swelling in the hands, ankles, and feet

Stop taking Viagra and call your doctor immediately if you experience any of these serious side effects.

Hives, difficulty breathing, swelling of the face, lips, tongue, or throat are signs of an allergic reaction. Get medical help immediately.

If your erection is painful or lasts for more than four hours (priapism), seek immediate medical attention, as permanent tissue damage and impotency could result.

Sildenafil may be found in some form under the following brand names:

• Revatio

• Viagra

• Sildenafil is not for newborns, children, or women.
• Do not let anyone else take your sildenafil.
• Sildenafil must be used only under a doctor's supervision.
• There is potential risk of sexual activity in patients with cardiovascular risk factors. If you experience symptoms (chest pain, dizziness, nausea) upon initiation of sexual activity, it is advised to refrain from further sexual activity and discuss the episode with your doctor.

• Sildenafil can cause your blood pressure to drop suddenly to an unsafe level if it is taken with certain other medicines. You could get dizzy, faint, or have a heart attack or stroke.
• Tell all of your healthcare providers that you take sildenafil. If you need emergency medical care for a heart problem, it will be important for your healthcare provider to know when you last took sildenafil.
• Seek immediate medical attention if sudden loss of vision occurs, which could be a sign of non-arteritic ischemic optic neuropathy (NAION).
• Seek immediate medical attention if sudden decrease or loss of hearing occurs.

Do not take sildenafil if you:

• take any medicines called “nitrates”. See "Drug Interactions" section.
• use recreational drugs called “poppers” like amyl nitrite and butyl nitrite
• are allergic to sildenafil or any of its ingredients. Symptoms of an allergic reaction may include:
  • rash
  • hives
  • swelling of the lips, tongue, or throat
  • difficulty breathing or swallowing
• Call your healthcare provider or get help right away if you have any of the symptoms of an allergic reaction listed above.
• Only your doctor can decide if sildenafil is right for you. Sildenafil can cause mild, temporary lowering of your blood pressure. You will need to have a thorough medical exam to diagnose your erectile dysfunction and to find out if you can safely take sildenafil alone or with your other medicines.

Keep sildenafil out of the reach of children. Keep sildenafil in its original container. Store at room temperature away from excessive heat or moisture.

You should not use sildenafil if you are allergic to it, or:

• if you take other medicines to treat pulmonary arterial hypertension, such as riociguat (Adempas).

Do not take sildenafil if you are also using a nitrate drug for chest pain or heart problems. This includes nitroglycerin, isosorbide dinitrate, and isosorbide mononitrate. Nitrates are also found in some recreational drugs such as amyl nitrate or nitrite ("poppers"). Taking sildenafil with a nitrate medicine can cause a sudden and serious decrease in blood pressure.

To make sure sildenafil is safe for you, tell your doctor about your other medical conditions, especially:

• heart disease or heart rhythm problems, coronary artery disease;

• a recent history (in the past 6 months) of a heart attack, stroke, or congestive heart failure;

• high or low blood pressure;

• liver or kidney disease;

• a blood cell disorder such as sickle cell anemia, multiple myeloma, or leukemia;

• a bleeding disorder such as hemophilia;

• a stomach ulcer;

• retinitis pigmentosa (an inherited condition of the eye);

• a physical deformity of the penis (such as Peyronie's disease); or

• if you have been told you should not have sexual intercourse for health reasons.

Sildenafil can decrease blood flow to the optic nerve of the eye, causing sudden vision loss. This has occurred in a small number of people taking sildenafil, most of whom also had heart disease, diabetes, high blood pressure, high cholesterol, or certain pre-existing eye problems, and in those who smoked or were over 50 years old. It is not clear whether sildenafil is the actual cause of vision loss.

This medicine is not expected to harm an unborn baby. Tell your doctor if you are pregnant or plan to become pregnant.

It is not known whether sildenafil passes into breast milk or if it could harm a nursing baby. Tell your doctor if you are breast-feeding a baby.

Do not give this medication to anyone under 18 years old without medical advice.

In the U.S.

• Revatio
• Viagra

Available Dosage Forms:

• Powder for Suspension
• Tablet

Therapeutic Class: Antihypertensive, Peripheral Vasodilator

Pharmacologic Class: Phosphodiesterase Type 5 Inhibitor

• Sildenafil Citrate
• UK92480

• Revatio
• Viagra

Adverse events were not observed in animal reproduction studies. Information related to the use of sildenafil for the treatment of pulmonary arterial hypertension (PAH) in pregnant women is limited (Hsu 2011). Women with pulmonary arterial hypertension are encouraged to avoid pregnancy (McLaughlin 2009; Taichman 2014). Less than 0.001% appears in the semen.

• Discuss specific use of drug and side effects with patient as it relates to treatment. (HCAHPS: During this hospital stay, were you given any medicine that you had not taken before? Before giving you any new medicine, how often did hospital staff tell you what the medicine was for? How often did hospital staff describe possible side effects in a way you could understand?)

• Patient may experience diarrhea, flushing, abdominal pain, heartburn, nausea, muscle pain, nosebleed, rhinitis, rhinorrhea, back pain, insomnia, or injection site pain, edema, or irritation. Have patient report immediately to prescriber signs of severe cerebrovascular disease (change in strength on one side is greater than the other, trouble speaking or thinking, change in balance, or change in eyesight), angina, tachycardia, arrhythmia, severe dizziness, passing out, severe headache, coughing up blood, severe nausea, severe vomiting, vision changes, blindness, hearing impairment, tinnitus, memory impairment, seizures, shortness of breath, swelling of hands and feet, or priapism (HCAHPS).

• Educate patient about signs of a significant reaction (eg, wheezing; chest tightness; fever; itching; bad cough; blue skin color; seizures; or swelling of face, lips, tongue, or throat). Note: This is not a comprehensive list of all side effects. Patient should consult prescriber for additional questions.

Intended Use and Disclaimer: Should not be printed and given to patients. This information is intended to serve as a concise initial reference for health care professionals to use when discussing medications with a patient. You must ultimately rely on your own discretion, experience, and judgment in diagnosing, treating, and advising patients.

Drinking alcohol with this medicine can cause side effects.

Grapefruit and grapefruit juice may interact with sildenafil and lead to unwanted side effects. Avoid the use of grapefruit products while taking sildenafil.

Avoid using any other medicines to treat impotence, such as alprostadil or yohimbine, without first talking to your doctor.

Usual Adult Dose of Sildenafil for Erectile Dysfunction:

Initial dose: 50 mg orally once a day, as needed, 1 hour prior to sexual activity
Maintenance: 25 to 100 mg orally once a day, as needed, 1 hour prior to sexual activity

Comments: This drug may be taken anywhere from 30 minutes to 4 hours before sexual activity.

Use: Treatment of erectile dysfunction

Usual Adult Dose for Pulmonary Hypertension:

Revatio (R):
Oral:
-Initial dose: 5 or 20 mg orally three times a day, 4 to 6 hours apart
-Maximum dose: 20 mg orally three times a day

Injection:
-Initial dose: 2.5 or 10 mg IV bolus three times a day

Comments:
-No greater efficacy was achieved with oral doses higher than the maximum recommended dose.
-A 10 mg injection dose is predicted to provide pharmacological effect equivalent to the 20 mg oral dose.

Use: Treatment of PAH (WHO Group I) in adults to improve exercise ability and delay clinical worsening

Usual Geriatric Dose of Sildenafil for Erectile Dysfunction:

Initial dose: 25 mg orally once a day 1 hour prior to sexual activity

Use: Treatment of erectile dysfunction

Do not take sildenafil with similar medications such as avanafil (Stendra), tadalafil (Cialis) or vardenafil (Levitra). Tell your doctor about all other medications you use for erectile dysfunction.

Tell your doctor about all your current medicines and any you start or stop using, especially:

• an antibiotic such as clarithromycin, erythromycin, or telithromycin;

• antifungal medicine such as ketoconazole or itraconazole;

• medicine to treat HIV/AIDS, such as atazanavir, indinavir, ritonavir, or saquinavir; or

• drugs to treat high blood pressure or a prostate disorder.

This list is not complete. Other drugs may interact with sildenafil, including prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible interactions are listed in this medication guide.

Commonly reported side effects of sildenafil include: dyspepsia, headache, visual disturbance, and flushing. Other side effects include: epistaxis, insomnia, nasal congestion, and rhinitis. See below for a comprehensive list of adverse effects.

Applies to sildenafil: intravenous solution, oral suspension, oral tablet

General

The most common adverse reactions reported in clinical trials are headache, flushing, dyspepsia, abnormal vision, nasal congestion, back pain, myalgia, nausea, dizziness, and rash.[Ref]

Cardiovascular

Very common (10% or more): Flushing (10%)
Uncommon (0.1% to 1%): Heart rate increased, palpitations, tachycardia, hypertension, hypotension
Rare (less than 0.1%): Myocardial infarction, atrial fibrillation, sudden cardiac death, ventricular arrhythmia, unstable angina
Frequency not reported: Ventricular arrhythmia, sudden cardiac death, angina pectoris, AV block, tachycardia, palpitation, hypotension, postural hypotension, myocardial ischemia, cerebral thrombosis, cardiac arrest, heart failure, abnormal electrocardiogram, cardiomyopathy, shock
Postmarketing reports: Serious cardiovascular, cerebrovascular, and vascular events, including myocardial infarction; sudden cardiac death; ventricular arrhythmia; cerebrovascular hemorrhage; transient ischemic attack; hypertension; subarachnoid, intracerebral, and pulmonary hemorrhage have been reported in temporal association with the use of this drug.[Ref]

Gastrointestinal

Very common (10% or more): Dyspepsia (up to 17%), diarrhea
Common (1% to 10%): Nausea, vomiting, dry mouth, gastritis, gastroesophageal reflux disease, hemorrhoids, abdominal distension
Rare (less than 0.1%): Oral hypoesthesia
Frequency not reported: Glossitis, colitis, dysphagia, gastroenteritis, esophagitis, stomatitis, gingivitis[Ref]

Musculoskeletal

Very common (10% or more): Pain in extremity
Common (1% to 10%): Back pain, myalgia
Frequency not reported: Arthritis, arthrosis, myalgia, tendon rupture, tenosynovitis, bone pain, myasthenia, synovitis[Ref]

Nervous system

Very common (10% or more): Headache (up to 28%)
Common (1% to 10%): Dizziness, migraine, tremor, paresthesia, burning sensation
Uncommon (0.1% to 1%): Somnolence, hypoesthesia
Rare (less than 0.1%): Cerebrovascular accident, syncope
Frequency not reported: Transient ischemic attack, seizure, seizure recurrence, ataxia, hypertonia, neuralgia, neuropathy, paresthesia, somnolence, reflexes decreased
Postmarketing reports: Transient global amnesia[Ref]

Ocular

Very common (10% or more): Abnormal vision (up to 11%)
Common (1% to 10%): Visual color distortion, retinal hemorrhage, visual impairment, vision blurred, photophobia, chromatopsia, cyanopsia, eye irritation, ocular hyperemia
Uncommon (0.1% to 1%): Conjunctival disorders, eye disorders, eye pain, lacrimation disorders, visual acuity reduced, diplopia, abnormal sensation in eye, photopsia, visual brightness, conjunctivitis
Rare (less than 0.1%): Retinal hemorrhage, arteriosclerotic retinopathy, retinal disorder, glaucoma, visual field defect, myopia, asthenopia, vitreous floaters, iris disorder, mydriasis, halo vision, eye edema, eye swelling, eyelid edema, scleral discoloration
Frequency not reported: Non-arteritic anterior ischemic optic neuropathy (NAION), retinal vascular occlusion, visual field defect, cataract[Ref]

This drug has lesser affinity for isoenzyme PDE6, an enzyme found in the retina. This lower selectivity is thought to be the basis for abnormalities related to color vision observed with higher doses or plasma levels.

Nonarteritic anterior ischemic optic neuropathy developed in one eye within minutes to hours after ingestion of sildenafil. Four of the five patients had no vascular risk factors for ischemic optic neuropathy.

-Abnormal Vision: Mild to moderate and transient, predominantly color tinge to vision, but also increased sensitivity to light, or blurred vision.
-Visual color distortions: Chloropsia, chromatopsia, cyanopsia, erythropsia and xanthopsia
-Lacrimation disorders: Dry eye, lacrimal disorder and lacrimation increased[Ref]

Respiratory

Very common (10% or more): Pharyngitis (18%), rhinitis
Common (1% to 10%): Nasal congestion, epistaxis, cough
Uncommon (0.1% to 1%): Sinus congestion
Rare (less than 0.1%): Throat tightness, nasal edema, nasal dryness
Frequency not reported: Asthma, dyspnea, laryngitis, pharyngitis, sinusitis, bronchitis, sputum increased, cough increased[Ref]

Dermatologic

Common (1% to 10%): Rash, alopecia, erythema, night sweats
Frequency not reported: Steven-Johnson syndrome (SJS), toxic epidermal necrolysis(TEN), urticaria, herpes simplex, pruritus, sweating, skin ulcer, contact dermatitis, exfoliative dermatitis[Ref]

Hematologic

Common (1% to 10%): Anemia
Frequency not reported: Leukopenia
Postmarketing reports: In patients with pulmonary arterial hypertension (secondary to sickle cell disease) taking Revatio (R), vaso-occlusive crises requiring hospitalization were more commonly reported. The clinical relevance of this finding in male patients treated with sildenafil for erectile dysfunction is unknown.[Ref]

Metabolic

Common (1% to 10%): Fluid retention
Frequency not reported: Thirst, edema, gout, unstable diabetes, hyperglycemia, hyperuricemia, hypoglycemic reaction, hypernatremia[Ref]

Other

Common (1% to 10%): Cellulitis, influenza, bronchitis, sinusitis, rhinitis, gastroenteritis, vertigo, pyrexia
Uncommon (0.1% to 1%): Tinnitus, chest pain, fatigue, gynecomastia
Rare (less than 0.1%): Deafness, irritability
Frequency not reported: Sudden hearing loss, edema, face edema, peripheral edema, pain, chills accidental fall, accidental injury[Ref]

Psychiatric

Common (1% to 10%): Insomnia, anxiety
Frequency not reported: Abnormal dreams, depression[Ref]

Genitourinary

Uncommon (0.1% to 1%): Penile hemorrhage, hematospermia
Frequency not reported: Priapism, prolonged erection, increased erection, cystitis, nocturia, urinary frequency, urinary incontinence, abnormal ejaculation, genital edema, anorgasmia[Ref]

Renal

Uncommon (0.1% to 1%): Hematuria[Ref]

Hypersensitivity

Rare (less than 0.1%): Hypersensitivity reactions, including rash and urticaria[Ref]

Hepatic

Frequency not reported: Liver function tests abnormal[Ref]

Some side effects of sildenafil may not be reported. Always consult your doctor or healthcare specialist for medical advice. You may also report side effects to the FDA.