Dapsone

Should be taken with food.

Hypersensitivity to dapsone. Severe anaemia, porphyria, severe G6PD deficiency. Congenital or idiopathic methaemoglobinaemia (topical).

Patient with history of hypersensitivity to sulfonamides; cardiac disease, pulmonary disease; mild to moderate anaemia, diabetes mellitus; deficiency in G6PD, methaemoglobin reductase or haemoglobin M. Hepatic impairment. Children. Pregnancy and lactation. Monitoring Parameters Obtain G6PD levels prior to treatment initiation; CBC at baseline, weekly for the 1st month, monthly for 6 months, then semi-annually thereafter; reticulocyte counts; LFTs at baseline then periodically thereafter. Monitor for signs of haemolysis, blood dyscrasias, liver impairment, and dermatologic reactions.

Significant: Haemolysis, methaemoglobinaemia, haemolytic anaemia; toxic hepatitis, cholestatic jaundice, hyperbilirubinaemia, peripheral neuropathy; fungal or bacterial superinfection with prolonged use (e.g. C. difficile-associated diarrhoea, pseudomembranous colitis). Cardiac disorders: Tachycardia. Gastrointestinal disorders: Nausea, vomiting, abdominal pain, pancreatitis. Hepatobiliary disorders: Hypoalbuminaemia. Investigations: Changes in LFTs. Metabolism and nutrition disorders: Anorexia. Nervous system disorders: Headache; tonic-clonic movements (topical). Psychiatric disorders: Psychoses, insomnia; suicide attempt (topical). Respiratory, thoracic and mediastinal disorders: Sinusitis, severe pharyngitis (topical). Skin and subcutaneous tissue disorders: Photosensitivity, rash, pruritus; application site oiliness or peeling, dryness, erythema (topical).
Potentially Fatal: Blood dyscrasias, including aplastic anaemia and agranulocytosis. Rarely, serious dermatologic reactions (e.g. toxic erythema, morbilliform and scarlatiniform reactions, erythema multiforme, toxic epidermal necrolysis, erythema nodosum, urticaria); dapsone syndrome.

Plasma concentrations may be increased by probenecid. May reduce the efficacy of oral typhoid vaccine. Increased plasma clearance with rifampicin or rifabutin. May increase the risk of arrhythmia with saquinavir. Elevation of both dapsone and trimethoprim plasma concentrations following concurrent administration in AIDS patients. Topical: May increase the risk of methaemoglobinaemia with methaemoglobin-inducing agents (e.g. oral dapsone, sulfonamides, paracetamol, nitrates and nitrites, chloroquine, primaquine, quinine, phenytoin, phenobarbital). May cause temporary local yellow or orange skin and facial hair discolouration with topical benzoyl peroxide. Increased levels of dapsone and its metabolites with trimethoprim/sulfamethoxazole combination.

Acne Treatment Preparations / Antileprotics

J04BA02 - dapsone ; Belongs to the class of drugs used in the systemic treatment of lepra.
D10AX05 - dapsone ; Belongs to the class of other topical preparations used in the treatment of acne.