Dapsone

Pregnancy category: C

Lactation: Enters breast milk; not recommended (AAP Committee states "compatible with nursing")

Pregnancy Categories

A:Generally acceptable. Controlled studies in pregnant women show no evidence of fetal risk.

B:May be acceptable. Either animal studies show no risk but human studies not available or animal studies showed minor risks and human studies done and showed no risk.

C:Use with caution if benefits outweigh risks. Animal studies show risk and human studies not available or neither animal nor human studies done.

D:Use in LIFE-THREATENING emergencies when no safer drug available. Positive evidence of human fetal risk.

X:Do not use in pregnancy. Risks involved outweigh potential benefits. Safer alternatives exist.

NA:Information not available.

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G6PD is an enzyme in your body that is responsible for helping red blood cells to work properly. Some patients are born with less of this enzyme in their bodies, leading to the destruction of red blood cells. When dapsone is used in patients with G6PD deficiency, they have a higher chance of experiencing hemolytic anemia (a condition in which the body does not have enough red blood cells to deliver oxygen to your tissues).

G6PD testing may be done to determine whether you are at a higher risk of experiencing hemolytic anemia if you are to be treated with dapsone. In addition, patients who are G6PD deficient may be more likely to experience jaundice (yellowing of the skin or eyes) while taking dapsone.

Your doctor will select an alternative medication as dapsone should not be given to patients with G6PD deficiency.

Serious side effects have been reported with dapsone. See the "Drug Precautions" section.

Common side effects of dapsone tablets include the following:

• nausea
• vomiting
• upset stomach
• trouble sleeping
• blurred vision
• headache
• fast heartbeat

Common side effects of dapsone gel include the following:

• oiliness/peeling of skin
• dry skin
• redness of the skin at the application site

This is not a complete list of dapsone side effects. Ask your doctor or pharmacist for more information.

Tell your doctor if you have any side effect that bothers you or that does not go away.

Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.

In addition to the warnings listed above, the following syndromes and serious reactions have been reported in patients on Dapsone.

Hematologic Effects

Dose-related hemolysis is the most common adverse effect and is seen in patients with or without G6PD deficiency. Almost all patients demonstrate the inter-related changes of a loss of 1-2g of hemoglobin, an increase in the reticulocytes (2-12%), a shortened red cell life span and a rise in methemoglobin. G6PD deficient patients have greater responses.

Nervous System Effects

Peripheral neuropathy is a definite but unusual complication of Dapsone therapy in non-leprosy patients. Motor loss is predominant. If muscle weakness appears, Dapsone should be withdrawn. Recovery on withdrawal is usually substantially complete. The mechanism of recovery is reported by axonal regeneration. Some recovered patients have tolerated retreatment at reduced dosage. In leprosy this complication may be difficult to distinguish from a leprosy reactional state.

Body As A Whole: In addition to the warnings and adverse effects reported above, additional adverse reactions include: nausea, vomiting, abdominal pains, pancreatitis, vertigo, blurred vision, tinnitus, insomnia, fever, headache, psychosis, phototoxicity, pulmonary eosinophilia, tachycardia, albuminuria, the nephrotic syndrome, hypoalbuminemia without proteinuria, renal papillary necrosis, male infertility, drug-induced Lupus erythematosus and an infectious mononucleosis-like syndrome. In general, with the exception of the complications of severe anoxia from overdosage (retinal and optic nerve damage, etc.) these adverse reactions have regressed off drug.

Read the entire FDA prescribing information for Dapsone (Dapsone)

Usual Adult Dose for Leprosy -- Lepromatous:

50 to 100 mg orally once a day for 2-5 years.

Usual Adult Dose for Leprosy -- Tuberculoid:

100 mg orally once a day for 6 months. Rifampin is additionally recommended to reduce the incidence of dapsone resistance. If the disease relapses, this regimen should be repeated.

Usual Adult Dose for Dermatitis Herpetiformis:

50 mg orally once a day continued on a life-long basis. Dosage may be advanced to 300 mg/day. Dosage reduction to a minimum maintenance level as soon as possible is recommended.

Usual Adult Dose for Pneumocystis Pneumonia:

100 mg orally once a day for 14 to 21 days. Used in combination with trimethoprim.

Usual Adult Dose for Pneumocystis Pneumonia Prophylaxis:

100 mg orally twice a week. Therapy should be continued on a life-long basis. The addition of pyrimethamine appears to significantly increase the activity of dapsone for PCP prophylaxis.

Usual Adult Dose for Toxoplasmosis -- Prophylaxis:

100 mg orally twice a week continued on a life-long basis.

Usual Pediatric Dose for Leprosy:

1 to 2 mg/kg (up to 100 mg) orally once a day.

Usual Pediatric Dose for Pneumocystis Pneumonia Prophylaxis:

> 1 month:
2 mg/kg/day (up to 100 mg) orally once a day.

Alternate dosing:
> 1 month:
4 mg/kg orally once weekly. Maximum dose = 200 mg.

Usual Pediatric Dose for Toxoplasmosis -- Prophylaxis:

> 1 month:

2 mg/kg/day (or 15 mg/m2) orally once a day. Maximum dose = 25 mg. Dapsone should be administered as part of combination therapy for prophylaxis of toxoplasmosis.

Leprosy

Treatment of leprosy (Hansen's disease) in conjunction with other anti-infectives.105 116 216 217 218

WHO and US National Hansen's Disease Program (NHDP) recommend multidrug therapy (MDT) for treatment of all forms of leprosy, including multibacillary leprosy and paucibacillary leprosy.216 217 218

MDT regimens can rapidly kill Mycobacterium leprae, render patient noninfectious after only a few days of treatment, delay or prevent emergence of resistant M. leprae, and reduce risk of relapse after treatment discontinuance.105 216 MDT regimens do not enhance rate of clearance of dead bacilli from the body;217 such clearance may take years216 and depends largely on individual's immune response, which may be defective in leprosy patients.217 Reactive episodes reported in leprosy patients receiving treatment appear to be due to destruction of M. leprae and immune responses to released bacterial antigens.216 217 (See Leprosy Reactional States under Cautions.)

For treatment of multibacillary leprosy (i.e., ≥6 lesions or skin smear positive) in adults, WHO recommends a 12-month MDT regimen of dapsone (once daily), rifampin (once monthly), and clofazimine (once daily and once monthly).217 218 For treatment of paucibacillary leprosy (i.e., 1–5 lesions) in adults, WHO recommends a 6-month MDT regimen of dapsone (once daily) and rifampin (once monthly).217 218

For US patients, NHDP recommends more prolonged treatment.216 NHDP recommends that adults with multibacillary leprosy (i.e., those who are skin smear positive and/or have biopsy indicating more advanced disease) receive a 24-month MDT regimen of dapsone (once daily), rifampin (once daily), and clofazimine (once daily), and that adults with paucibacillary leprosy (i.e., those who are skin smear negative without evidence of more advanced disease on biopsy) receive a 12-month MDT regimen of dapsone (once daily) and rifampin (once daily).216 Clofazimine (no longer commercially available in US) may be obtained from NHDP under an investigational new drug (IND) protocol for treatment of leprosy.216

Treatment of leprosy is complicated and should be undertaken in consultation with a specialist familiar with the disease.105 116 In the US, clinicians should contact NHDP at 800-642-2477 on weekdays from 9:00 a.m. to 5:30 p.m. Eastern Standard Time or via email at nhdped@hrsa.gov for assistance with diagnosis or treatment of leprosy or assistance obtaining clofazimine for treatment of leprosy.216

Dermatitis Herpetiformis

Treatment of dermatitis herpetiformis.116 211

Gluten-free diet recommended for all patients with dermatitis herpetiformis; strict adherence to such a diet can result in slow resolution of skin lesions (may take months to years) and improvement in GI symptoms.211 Dapsone, used as an adjunct to gluten-free diet,211 usually results in prompt decrease in pruritus and resolution of skin lesions in responsive patients.116 211 Dapsone has no effect on GI component of dermatitis herpetiformis.116 211

Some patients who adhere to strict gluten-free diet may be able to decrease dapsone dosage or discontinue the drug after several months when skin manifestations have responded; may then reinitiate dapsone for brief periods as needed to control flares.211

Pneumocystis jirovecii Pneumonia

Alternative for treatment and prevention of Pneumocystis jirovecii (formerly Pneumocystis carinii) pneumonia† (PCP) in adults, adolescents, or children.110 134 153 154 155 156 161 174 176 Designated an orphan drug by FDA for treatment and prevention of PCP.185

Co-trimoxazole is drug of choice for treatment of mild, moderate, or severe PCP in adults, adolescents, and children, including HIV-infected individuals.134 155 156

Dapsone in conjunction with trimethoprim is one of several alternatives recommended by CDC, NIH, and IDSA for treatment of mild to moderate PCP† in HIV-infected adults and adolescents when co-trimoxazole cannot be used.155 Although efficacy and safety data limited regarding use for treatment of PCP in children,156 some clinicians also recommend dapsone in conjunction with trimethoprim as an alternative for treatment of mild to moderate PCP in children†.134 Not included in CDC, NIH, IDSA, and AAP recommendations for treatment of severe PCP.134 155 156

Recommended by CDC, NIH, and IDSA as alternative for prevention of initial episode of PCP (primary prophylaxis)† in HIV-infected adults and adolescents who cannot tolerate drug of choice (co-trimoxazole);155 used alone or in conjunction with pyrimethamine (and leucovorin) for primary PCP prophylaxis in HIV-infected adults and adolescents.155

Recommended by CDC, NIH, and IDSA as alternative for long-term suppressive or chronic maintenance therapy (secondary prophylaxis) of PCP† in HIV-infected adults and adolescents who cannot tolerate drug of choice (co-trimoxazole);155 used alone or in conjunction with pyrimethamine (and leucovorin) for secondary PCP prophylaxis in HIV-infected adults and adolescents.155

Recommended by CDC, NIH, IDSA, and AAP as alternative for primary and secondary PCP prophylaxis in HIV-infected children and infants ≥1 month of age† who cannot tolerate drug of choice (co-trimoxazole);156 used alone for primary and secondary PCP prophylaxis in HIV-infected pediatric patients.156

Toxoplasmosis

Alternative for primary prophylaxis to prevent initial episode of toxoplasmosis caused by Toxoplasma gondii† in HIV-infected adults, adolescents, and children.134 155 156 Designated an orphan drug by FDA for toxoplasmosis prophylaxis in severely immunocompromised individuals with CD4+ T-cell counts <100/mm3.185

Recommended by CDC, NIH, and IDSA as preferred alternative for prevention of initial episodes of toxoplasmosis (primary prophylaxis)† in HIV-infected adults and adolescents who cannot tolerate drug of choice (co-trimoxazole);155 used in conjunction with pyrimethamine (and leucovorin) for primary toxoplasmosis prophylaxis in HIV-infected adults and adolescents.155

Recommended by CDC, NIH, IDSA, and AAP as preferred alternative for primary toxoplasmosis prophylaxis† in HIV-infected children and infants ≥1 month of age who cannot tolerate drug of choice (co-trimoxazole);156 used in conjunction with pyrimethamine (and leucovorin) for primary toxoplasmosis prophylaxis in HIV-infected pediatric patients.156

Not included in CDC, NIH, IDSA, and AAP recommendations for treatment of toxoplasmosis or chronic maintenance therapy to prevent relapse of toxoplasmosis (secondary prophylaxis) in HIV-infected adults, adolescents, and children.155 156

Absorption

Bioavailability

Rapidly and almost completely absorbed from GI tract.116 Peak serum concentrations attained within 2–8 hours.116

At least 8 days of daily administration is necessary to attain steady-state concentrations; steady-state serum concentrations average 2.3 mcg/mL (range 0.1–7 mcg/mL) with an oral dosage of 200 mg daily.116

Distribution

Extent

Distributes into most tissues.a

Crosses the placenta.128

Distributed into human milk.116

Plasma Protein Binding

50–90% bound to plasma proteins.128 135 136

Monoacetyldapsone (the major metabolite) is almost completely bound to plasma proteins.128 135 136

Elimination

Metabolism

Metabolized by acetylation in the liver to monoacetyl and diacetyl derivatives.128 a Rate of acetylation is genetically determined.a

Elimination Route

20% of dose excreted in urine as unchanged drug;a 70–85% excreted in urine as water-soluble metabolites;116 a small amount excreted in feces.a

Hemodialysis enhances elimination of dapsone and its monoacetyl derivative.104

Half-life

Average 20–30 hours (range 10–83 hours).116 a Large interindividual variation.116 a

• Bacteriostatic and weakly bactericidal against Mycobacterium leprae.116 216 217

• Antibacterial activity of dapsone is inhibited by p-aminobenzoic acid (PABA).a Therefore, it probably has a mechanism of action similar to that of sulfonamides which involves inhibition of folic acid synthesis in susceptible organisms.a

• May inhibit alternate pathway of complement activation and interfere with the myeloperoxidase-H2O2-halide-mediated cytotoxic system within neutrophils.126 127

• Stimulates neutrophil motility and121 126 inhibits spontaneous and induced synthesis of prostaglandin E2 by polymorphonuclear leukocytes obtained from healthy individuals or patients with leprosy.122 123

• Mechanism of action in treatment of dermatitis herpetiformis unknown.116 Dapsone only suppresses the disease; cutaneous IgA and complement deposition not affected by the drug.a May act as an immunomodulator when used in the treatment of this and other dermatologic diseases.a

• Active against M. leprae,116 a M. tuberculosis,a and some other mycobacteria.a Has some activity against Pneumocystis jirovecii (formerly Pneumocystis carinii)110 111 112 and Plasmodium.a

• Resistance to dapsone may occur in M. leprae;116 strains resistant to both dapsone and clofazimine, but susceptible to rifampin, reported rarely.117

Excipients in commercially available drug preparations may have clinically important effects in some individuals; consult specific product labeling for details.

Please refer to the ASHP Drug Shortages Resource Center for information on shortages of one or more of these preparations.

* available from one or more manufacturer, distributor, and/or repackager by generic (nonproprietary) name

For patients taking dapsone for leprosy:

• To help clear up your leprosy completely or to keep it from coming back, it is very important that you keep taking dapsone for the full time of treatment, even if you begin to feel better after a few weeks or months. You may have to take it every day for as long as 3 years or more, or for life. If you stop taking dapsone too soon, your symptoms may return.
• dapsone works best when there is a constant amount in the blood. To help keep the amount constant, do not miss any doses. Also, it is best to take each dose at the same time every day. If you need help in planning the best time to take your medicine, check with your health care professional.

For patients taking dapsone for dermatitis herpetiformis:

• Your doctor may want you to follow a gluten-free diet. If you have any questions about this, check with your doctor.

Dosing

The dose of dapsone 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 dapsone. 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 form (tablets):
  • For Hansen's disease (leprosy):
    • Adults and teenagers—50 to 100 milligrams (mg) once a day; or 1.4 mg per kilogram (kg) (0.6 mg per pound) of body weight once a day. Dapsone should be taken with other medicines to treat Hansen's disease.
    • Children—Dose is based on body weight. The usual dose is 1.4 mg per kg (0.6 mg per pound) of body weight once a day. Dapsone should be taken with other medicines to treat Hansen's disease.
  • For dermatitis herpetiformis:
    • Adults and teenagers—50 mg once a day to start. Your doctor will increase your dose, up to 300 mg once a day, until your symptoms are controlled. Then your dose will be decreased to the lowest dose that will still control your symptoms.
    • Children—Dose is based on body weight. The usual dose is 2 mg per kg (0.9 mg per pound) of body weight once a day to start. Your doctor will increase your dose until your symptoms are controlled. Then your dose will be decreased to the lowest dose that will still control your symptoms.

Missed Dose

If you miss a dose of dapsone, 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.

You may skip a missed dose if it does not make your symptoms come back or get worse. If your symptoms do come back or get worse, take the missed dose as soon as possible.

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.

Dapsone-USP, 4,4'-diaminodiphenylsulfone (DDS), is a primary treatment for Dermatitis herpetiformis. It is an antibacterial drug for susceptible cases of leprosy. It is a white, odorless crystalline powder, practically in-soluble in water and insoluble in fixed and vegetable oils.

Dapsone is issued on prescription in tablets of 25 and 100 mg for oral use.

Inactive Ingredients: Colloidal silicone dioxide, magnesium stearate, microcrystalline cellulose and corn starch.

The patient should be warned to respond to the presence of clinical signs such as sore throat, fever, pallor, purpura or jaundice. Deaths associated with the administration of Dapsone have been reported from agranulocytosis, aplastic anemia and other blood dyscrasias. Complete blood counts should be done frequently in patients receiving Dapsone. The FDA Dermatology Advisory Committee recommended that, when feasible, counts should be done weekly for the first month, monthly for six months and semi-annually thereafter. If a significant reduction in leucocytes, platelets or hemopoiesis is noted, Dapsone should be discontinued and the patients followed intensively. Folic acid antagonists have similar effects and may increase the incidence of hematologic reactions; if co-administered with Dapsone the patient should be monitored more frequently. Patients on weekly pyrimethamine and Dapsone have developed agranulocytosis during the second and third month of therapy.

Severe anemia should be treated prior to initiation of therapy and hemoglobin monitored. Hemolysis and methemoglobin may be poorly tolerated by patients with severe cardiopulmonary disease.

Cutaneous reactions, especially bullous, include exfoliative dermatitis and are probably one of the most serious, though rare, complications of sulfone therapy. They are directly due to drug sensitization. Such reactions include toxic erythema, erythema multiforme, toxic epidermal necrolysis, morbilliform and scarlatiniform reactions, urticaria and erythema nodosum. If new or toxic dermatologic reactions occur, sulfone therapy must be promptly discontinued and appropriate therapy instituted. Leprosy reactional states, including cutaneous, are not hypersensitivity reactions to Dapsone and do not require discontinuation. See special section.

Applies to dapsone: oral tablet

Hematologic

Hematologic side effects have been the most pronounced. These have included methemoglobinemia, aplastic anemia, leukopenia, agranulocytosis, eosinophilia, macrocytic anemia, and Heinz bodies. Dapsone may induce a dose-related hemolytic anemia, which is more likely with doses greater than 200 mg/day or in patients with glucose-6-phosphate dehydrogenase (G-6-PD) deficiency. Leukopenia, megaloblastic pancytopenia, and hemolysis have been reported. At least one case of pure red cell aplasia has also been reported, in addition to a case of exanthema with desquamation of the trunk and extremities.[Ref]

Agranulocytosis usually occurs during the first few months of therapy and has been fatal. In one case report, filgrastim (G-CSF) was used to control the agranulocytosis.

Dapsone may induce methemoglobinemia, which may be important in patients with underlying respiratory insufficiency, anemia, or cardiovascular disease. Patients with methemoglobinemia may show normal oxygen saturation by pulse oximetry and by arterial blood gas (ABG). The diagnosis is based on cyanosis, dyspnea (usually only in patients with underlying respiratory insufficiency), elevated methemoglobin level from ABG sampling, and reversal of brown blood to red after addition of cyanide in vitro. Methemoglobin levels exceeding 10% may lead to peripheral cyanosis. Concentrations greater than 35% often produce symptoms of weakness, headache, or dyspnea, while those greater than 70% may result in fatality.

Recent data indicate vitamin E may be protective against dapsone-induced hemolytic anemia and methemoglobinemia, although more studies are needed.

Aplastic anemia due to dapsone has been reported occasionally. The onset of aplastic anemia has ranged from 2 to 12 weeks following initiation of therapy and has been fatal.

A 75-year-old male with granuloma annulare experienced pure red cell aplasia (PRCA) coincident with dapsone therapy. He was given dapsone 100 mg per day. Four weeks after the start of this therapy, the patient presented with asthenia. A diagnosis of PRCA was made based off of hematological counts. Dapsone was discontinued, and the patient received blood transfusions until his condition improved considerably. Hematological counts gradually returned to normal levels.[Ref]

Nervous system

Peripheral neuropathy often affects the hands, resulting in thenar, hypothenar, and interosseous muscle atrophy. Rare cases of pure sensory loss associated with dapsone-induced peripheral neuropathy have been reported. In the treatment of leprosy, peripheral neuropathy may be difficult to distinguish from that of a leprosy reactional state. There has also been an isolated case of optic atrophy reported in a patient receiving dapsone 600 mg/day for 10 days.[Ref]

Nervous system side effects have included peripheral neuropathy and manifested predominantly as motor deficits, but in up to 40% of cases, also included sensory loss. The peripheral neuropathy is reversible upon discontinuation of dapsone. Dizziness, vertigo, blurred vision, and headache have also been reported. At least one case of paresthesias has also been reported.[Ref]

Gastrointestinal

Gastrointestinal side effects have included mild nausea, vomiting, and abdominal pains.[Ref]

Hepatic

Hepatic side effects have frequently included elevations in liver function tests, which may occur as part of the dapsone syndrome. Rare cases of hepatitis and cholestatic jaundice have been reported. Hyperbilirubinemia has also been reported.[Ref]

Hyperbilirubinemia may occur more often in patients with glucose-6-phosphate dehydrogenase (G-6-PD) deficiency.[Ref]

Respiratory

Respiratory side effects including at least two cases of pulmonary eosinophilia have been reported. One patient received pyrimethamine and dapsone, and the other patient received just dapsone. Both patients recovered upon drug withdrawal.[Ref]

Immunologic

Rare cases of dapsone-induced lupus erythematosus and exacerbations of existing lupus erythematosus have been reported.[Ref]

Psychiatric

Psychiatric side effects have rarely included depression, psychosis, and hypomania.[Ref]

Hypersensitivity

A 39-year-old female with paucibacillary leprosy experienced renal hypersensitivity vasculitis coincident with dapsone therapy. She was prescribed dapsone 100 mg per day and rifampicin 600 mg per month. After 23 days of treatment, she stopped treatment because of low fever, headache, dizziness, and weakness. On presentation, in addition to the symptoms described, the patient was toxic with fever, respiratory discomfort, dry cough, jaundice, hepatomegaly, and arterial hypotension. She developed edema and pruritus of the face, with a vesicopustular skin rash. The skin rash worsened to exfoliative erythroderma, associated with purpura of the lower extremities. Severe acute failure and oliguria were observed within 4 days after admission. On day 7, kidney histopathologic and immunohistochemical studies illustrated interstitial perivascular lymphocytic infiltrate affecting the media of arched and interlobular arteries, composed of T cells. The patient's renal function and dermatological condition normalized 2 months after admission.[Ref]

Hypersensitivity side effects have been commonly reported, especially in HIV-infected patients. Rash has been reported the most frequently. Stevens-Johnson syndrome, toxic erythema, erythema multiforme, toxic epidermal necrolysis, and morbilliform and scariatiniform reactions have been reported in a few patients treated with dapsone or other sulfone agents. Rare cases of dapsone-induced lupus erythematosus and exacerbations of existing lupus erythematosus have been reported. Sulfone syndrome has been reported. At least one case of renal hypersensitivity vasculitis has also been reported.[Ref]

Renal

Renal side effects have rarely included nephritic syndrome and renal papillary necrosis.[Ref]

Other

Other side effects including the "dapsone syndrome" have been reported. The "dapsone syndrome" is manifested by viral illness-like symptoms (fever, chills, myalgias, arthralgias, exanthema, lymphadenopathy, edema, lymphocytosis), hepatomegaly, elevated liver function tests, methemoglobinemia, and anemia. Some or all of these signs and symptoms may be present in less than 0.5% of patients. Dapsone syndrome usually occurs within the first 6 weeks of therapy and may be fatal. The dapsone syndrome is neither dose-related nor predictable. It is often confused with infectious mononucleosis.[Ref]

"Leprosy reactional states" can commonly occur as a result of effective treatment for leprosy. They are generally classified into two types: reversal reactions (type 1) and erythema nodosum leprosum (ENL or type 2). Reversal reactions primarily occur in borderline or tuberculoid leprosy patients soon after the initiation of chemotherapy and consist of fever and swelling of existing skin and nerve lesions. Acute neuritis may develop. ENL occurs mostly in lepromatous patients (approximately 50% of treated patients within the first year) and a small number of borderline patients. Manifestations include fever and tender erythematous skin nodules sometimes associated with malaise, neuritis, orchitis, albuminuria, joint swelling, iritis, epistaxis or depression. In addition, skin lesions may become pustular and/or ulcerate. Histologically, there is vasculitis with an intense polymorphonuclear infiltrate. In general, antileprosy treatment is continued. Patients with severe reactions require hospitalization. Therapeutic management for reversal reactions may include administration of analgesics and/or corticosteroids and surgical decompression of swollen nerve trunks. Analgesics, corticosteroids, and other agents may be used for ENL reactions. For guidance concerning the management of reactional states, the Gillis W. Long Hansen's Disease Center in Carville, Louisiana (tel: 800-642-2477) should be contacted.[Ref]

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

100 mg orally twice a week. Therapy should be continued on a life-long basis. The addition of pyrimethamine appears to significantly increase the activity of dapsone for PCP prophylaxis.

Dapsone has been assigned to pregnancy category C. There are no animal data or controlled data in human pregnancies. Experience with dapsone during all trimesters of human pregnancy has not indicated an increased risk of fetal abnormalities. Dapsone should only be given during pregnancy when benefit outweighs risk.