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Pyrimethamine / sulfadoxine Side Effects

Medically reviewed by Drugs.com. Last updated on Aug 21, 2022.

Applies to pyrimethamine / sulfadoxine: oral tablet

Hypersensitivity

Severe cutaneous reactions have occurred in patients who have taken as few as two doses of pyrimethamine-sulfadoxine. The risk of fatal cutaneous reactions in patients receiving pyrimethamine-sulfadoxine has been estimated to range from 1 in 11,000 to 1 in 25,000. In general, the use of sulfonamide antibiotics is associated with large increases in the risk of Stevens-Johnson syndrome or toxic epidermal necrolysis, although these phenomena are rare as a whole.[Ref]

Hypersensitivity reactions have included erythema multiforme, Stevens-Johnson syndrome, generalized skin eruptions, toxic epidermal necrolysis, urticaria, serum sickness, pruritus, exfoliative dermatitis, anaphylactoid reactions, periorbital edema, conjunctival and scleral injection, photosensitization, arthralgia, and allergic pericarditis. Fatalities due to severe hypersensitivity reactions have been reported.[Ref]

Dermatologic

Dermatologic side effects have frequently included phototoxicity, rash, dermatitis, and hair loss.[Ref]

Hematologic

Hematologic toxicity is more common with higher doses of pyrimethamine.

Many cases of agranulocytosis have occurred during therapy with pyrimethamine-dapsone, although it has been reported in patients receiving pyrimethamine-sulfadoxine as well.[Ref]

Hematologic side effects have included leucopenia (7%), agranulocytosis, aplastic anemia, megaloblastic anemia, thrombocytopenia, hemolytic anemia, purpura, hypoprothrombinemia, methemoglobinemia, and eosinophilia. Macrocytic anemia has also been reported. Fatalities have been reported.[Ref]

Gastrointestinal

Gastrointestinal side effects have included anorexia (5.5%), digestive intolerance (3%), diarrhea (2.74%), abdominal pain (2.74%), vomiting (2.74%), nausea, glossitis, stomatitis, and pancreatitis.[Ref]

Hepatic

Hepatic side effects have included hepatitis (7%), hepatocellular necrosis, and liver enzyme elevations.[Ref]

In many cases, the hepatitis has accompanied severe cutaneous reactions, fever, myalgias and arthralgias. Granulomas and necrosis have been seen on biopsy.[Ref]

Renal

Renal side effects have included renal failure, interstitial nephritis, toxic nephrosis with oliguria and anuria, crystalluria, and increases in BUN and serum creatinine.[Ref]

Respiratory

Respiratory side effects have included cough (9.6%), pulmonary infiltrates and shortness of breath which may be due to pulmonary hypersensitivity reactions. Frequently, the pulmonary reactions have accompanied other systemic symptoms.[Ref]

Nervous system

Nervous system side effects have included headache (4.1%), peripheral neuritis, mental depression, convulsions, ataxia, hallucinations, tinnitus, vertigo, insomnia, apathy, fatigue, muscle weakness, nervousness, and polyneuritis.[Ref]

Metabolic

Metabolic side effects associated with sulfonamides have included diuresis and hypoglycemia. Sulfonamides are chemically similar to goitrogenic agents (i.e., diuretics and oral hypoglycemic agents).[Ref]

Genitourinary

Genitourinary side effects have included crystalluria.[Ref]

Endocrine

Endocrine side effects including weight gain (1 kg or greater) have been reported in 53% of patients.

Other

Other side effects have included drug fever, chills, periarteritis nodosa, and lupus erythematosus phenomenon.[Ref]

References

1. "Product Information. Fansidar (pyrimethamine-sulfadoxine)." Roche Laboratories (2022):

2. Roujeau JC, Kelly JP, Naldi L, et al. "Medication use and the risk of Stevens-Johnson syndrome or toxic epidermal necrolysis." N Engl J Med 333 (1995): 1600-7

3. Zitelli BJ, Alexander J, Taylor S, Miller KD, Howrie DL, Kuritsky JN, Perez TH, Van Thiel DH "Fatal hepatic necrosis due to pyrimethamine-sulfadoxine (Fansidar)." Ann Intern Med 106 (1987): 393-5

4. Selby CD, Ladusans EJ, Smith PG "Fatal multisystemic toxicity associated with prophylaxis with pyrimethamine and sulfadoxine (Fansidar)." Br Med J (Clin Res Ed) 290 (1985): 113-4

5. Murphy RL, Phair JP "Systemic reaction to pyrimethamine-sulfadoxine." J Fam Pract 22 (1986): 375-6

6. Phillips-Howard PA, West LJ "Serious adverse drug reactions to pyrimethamine-sulphadoxine pyrimethamine-dapsone and to amodiaquine in Britain." J R Soc Med 83 (1990): 82-5

7. Whitfield D "Presumptive fatality due to pyrimethamine-sulfadoxine." Lancet 2 (1982): 1272

8. Olsen VV, Loft S, Christensen KD "Serious reactions during malaria prophylaxis with pyrimethamine- sulfadoxine." Lancet 2 (1982): 994

9. Phillips-Howard PA, Behrens RH, Dunlop J "Stevens-Johnson syndrome due to pyrimethamine / sulfadoxine during presumptive self-therapy of malaria." Lancet 2 (1989): 803-4

10. "Fansidar-associated fatal reaction in an HIV-infected man." MMWR Morb Mortal Wkly Rep 37 (1988): 571-2

11. Hornstein OP, Ruprecht KW "Fansidar-induced Stevens-Johnson Syndrome." N Engl J Med 307 (1982): 1529-30

12. Jeffrey RF "Transient lupus anticoagulant and fansidar therapy." Postgrad Med J 62 (1986): 893-4

13. Adams SJ, Broadbent J, Clayden LM, Ridley CM "Erythema multiforme (Stevens-Johnson) precipitated by Fansidar." Postgrad Med J 61 (1985): 263-4

14. Ward DJ, Krzeminska EC, Tanner NS "Treatment of toxic epidermal necrolysis and a review of six cases." Burns 16 (1990): 97-104

15. Ortel B, Sivayathorn A, Honigsmann H "An unusual combination of phototoxicity and Stevens-Johnson syndrome due to antimalarial therapy." Dermatologica 178 (1989): 39-42

16. Bamber MG, Elder AT, Gray JA, Minns RA "Fatal Stevens-Johnson syndrome associated with Fansidar and chloroquine." J Infect 13 (1986): 31-3

17. Ree GH "Chemoprophylaxis of malaria in Africa." Br Med J (Clin Res Ed) 286 (1983): 562

18. Nicholls MD, Concannon AJ "Maloprim-induced agranulocytosis and red-cell aplasia." Med J Aust 2 (1982): 564-6

19. Booth F, Barker LC, Barton CJ, Naik RB "Agranulocytosis during malaria prophylaxis with Maloprim (pyrimethamine and dapsone)." Postgrad Med J 60 (1984): 566-7

20. Bowcock SJ, Linch DC, Machin SJ, Stewart JW "Pyrimethamine in the myeloproliferative disorders: a forgotten treatment?" Clin Lab Haematol 9 (1987): 129-36

21. Whitehead S "Agranulocytosis associated with maloprim." Br Med J (Clin Res Ed) 286 (1983): 1515

22. Winstanley P "Malaria: treatment." J R Coll Physicians Lond 32 (1998): 203-7

23. Lazar HP, Murphy RL, Phair JP "Fansidar and hepatic granulomas." Ann Intern Med 102 (1985): 722

24. Davidson AC, Bateman C, Shovlin C, Marrinan M, Burton GH, Cameron IR "Pulmonary toxicity of malaria prophylaxis." BMJ 297 (1988): 1240-1

25. Svanbom M, Rombo L, Gustafsson L "Unusual pulmonary reaction during short term prophylaxis with pyrimethamine-sulfadoxine (Fansidar)." Br Med J (Clin Res Ed) 288 (1984): 1876

26. McCormack D, Morgan WK "Fansidar hypersensitivity pneumonitis." Br J Dis Chest 81 (1987): 194-6

27. Pang JA "Non-cardiogenic pulmonary oedema associated with pyrimethamine." Respir Med 83 (1989): 247-8

28. Fish DR, Espir ML "Convulsions associated with prophylactic antimalarial drugs: implications for people with epilepsy." BMJ 297 (1988): 526-7

Further information

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Some side effects may not be reported. You may report them to the FDA.