title: Hypersensitivity syndrome associated with dapsone/pyrimethamine (Maloprim) antimalaria chemoprophylaxis.
abstract: BACKGROUND
  Dapsone 100 mg/pyrimethamine 12.5 mg (Maloprim; Beacons Chemicals Pte Ltd, Singapore) is routinely prescribed for antimalarial chemoprophylaxis in military servicemen in Singapore who are not glucose-6-phosphate dehydrogenase-deficient.
  
  
  METHODS
  We report a series of three male National Servicemen with hypersensitivity syndrome from Maloprim.
  
  
  RESULTS
  The three patients were diagnosed with hypersensitivity syndrome based on the presence of features of a drug hypersensitivity syndrome including fever, lymphadenopathy, maculopapular exanthema, hepatitis, and definite exposure to weekly Maloprim alone. A mild Coombs positive hemolytic anemia was also observed in one patient. All the clinical, hematologic, and biochemical derangements normalized within 3 months of tapering regimens of moderate-dose prednisolone.
  
  
  CONCLUSIONS
  Drug hypersensitivity syndromes can occur even on low-dose, weekly drug regimens. Hypersensitivity syndrome from weekly Maloprim is potentially reversible when recognized and treated early.
authors.affiliation: Department of Rheumatology, Allergy and Immunology, Tan Tock Seng Hospital, Singapore. bernard_thong@ttsh.com.sg
authors.forename: Bernard Yu-Hor
authors.initials: BY
authors.lastname: Thong
authors.forename: Khai-Pang
authors.initials: KP
authors.lastname: Leong
authors.forename: Hiok-Hee
authors.initials: HH
authors.lastname: Chng
mesh_terms: D000328:Adult; D000962:Antimalarials / Q000009:adverse effects*; D003622:Dapsone / Q000009:adverse effects*; D004338:Drug Combinations; D004342:Drug Hypersensitivity / Q000188:drug therapy / Q000209:etiology*; D005938:Glucocorticoids / Q000627:therapeutic use; D006801:Humans; D008288:Malaria / Q000517:prevention & control*; D008297:Male; D008889:Military Personnel; D011239:Prednisolone / Q000627:therapeutic use; D011739:Pyrimethamine / Q000009:adverse effects*
chemical_list: D000962:Antimalarials; D004338:Drug Combinations; D005938:Glucocorticoids; C001678:Maloprim; D003622:Dapsone; D011239:Prednisolone; D011739:Pyrimethamine