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Therapeutic action
- Combination of two antibacterials: a sulfonamide (sulfamethoxazole) and a diaminopyrimidine antifolate (trimethoprim)
Indications
- Treatment of cerebral toxoplasmosis, pneumocystosis, isosporiasis, cyclosporiasis and brucellosis
- Prophylaxis of pneumocystosis, toxoplasmosis and isosporiasis
- Second-line treatment of pertussis
- Uncomplicated typhoid fever if the strain is susceptible (recent drug susceptibility test)
Forms and strengths
- 400 mg SMX + 80 mg TMP and 800 mg SMX + 160 mg TMP tablets
- 100 mg SMX + 20 mg TMP dispersible tablet for paediatric use
Dosage
Treatment of cerebral toxoplasmosis
- Child 1 month and over and adult: 25 mg SMX + 5 mg TMP/kg 2 times daily
Treatment of pneumocystosis
- Child 1 month and over: 50 mg SMX + 10 mg TMP/kg (max. 1600 mg SMX + 320 mg TMP) 2 times daily
- Adult: 1600 mg SMX + 320 mg TMP 3 times daily
Treatment of isosporiasis and cyclosporiasis
- Adult: 800 mg SMX + 160 mg TMP 2 times daily
Prophylaxis of pneumocystosis, toxoplasmosis and isosporiasis
- Child 1 month and over: 50 mg SMX + 10 mg TMP/kg (max. 800 mg SMX + 160 mg TMP) once daily, as long as necessary
- Adult: 800 mg SMX + 160 mg TMP once daily, as long as necessary
Treament of pertussis, brucellosis and typhoid fever
- Child 1 month and over: 20 mg SMX + 4 mg TMP/kg (max. 800 mg SMX + 160 mg TMP) 2 times daily
- Adult: 800 mg SMX + 160 mg TMP 2 times daily
Duration
- Cyclosporiasis: 7 days
- Isosporiasis: 7 to 10 days
- Typhoid fever, pertussis: 14 days
- Pneumocystosis: 21 days
- Cerebral toxoplasmosis: 4 to 6 weeks
- Brucellosis: 6 weeks
Contra-indications, adverse effects, precautions
- Do not administer to children under 1 month.
- Do not administer to sulfonamide-allergic patients; patients with severe renal or hepatic impairment.
- Do not combine with phenytoin (increased plasma concentrations of phenytoin).
- May cause:
- gastrointestinal disturbances, hepatic or renal disorders (crystalluria, etc.), metabolic disorders (hyperkalaemia, hypoglycaemia, hyponatraemia); neuropathy, photosensitivity, haemolytic anaemia in patients with G6PD deficiency;
- allergic reactions (fever, rash, etc.) sometimes severe (Lyell's and Stevens-Johnson syndromes, haematological disorders, etc.); agranulocytosis, megaloblastic anaemia due to folic acid deficiency. In these cases, stop treatment immediately.
- Adverse effects occur more frequently in patients with HIV infection.
- In the event of prolonged treatment, monitor blood count if possible.
- Avoid combination with drugs inducing hyperkalaemia: potassium salts, spironolactone, enalapril, NSAIDs, heparin (increased risk of hyperkalaemia).
- Monitor combination with: zidovudine (increased haematotoxicity), antidiabetics (increased risk of hypoglycaemia).
- Drink plenty of water during treatment to reduce risk of crystalluria.
- Pregnancy: avoid using during the first trimester (risk of malformation) and during the last month of pregnancy (risk of neonatal jaundice and haemolytic anaemia).
- Breast-feeding: avoid if premature neonate, jaundice, low-birth weight, during the first month of life. If co-trimoxazole is used, observe the child for signs of jaundice.
Remarks
- Preferably take during meals.
Storage
– Below 25 °C