Acenocoumarol
Adverse Effect: increased risk of bleeding Clinical Management: In patients receiving Acenocoumarol , the prothrombin time ratio or international normalized ratio (INR) should be closely monitored with the addition and withdrawal of Cotrimoxazole and should be reassessed periodically during concurrent therapy.
Amantadine
Adverse Effect: CNS toxicity (insomnia, confusion) Clinical Management: Patients, especially the elderly, treated concurrently with amantadine and trimethoprim or cotrimoxazole should be monitored for signs of central nervous system toxicity (insomnia, confusion, depression, hallucinations, anorexia, dizziness).
Azathioprine
Adverse Effect: Exaggerated leukopenia #Clinical Management: Monitor for signs and symptoms of leukopenia & institute supportive therapy.
Benzocaine
Adverse Effect: antagonism of Cotrimoxazole antibacterial effect Clinical Management: Avoid use of Benzocaine or para amino benzoic acid (PABA) derivatives in patients receiving Cotrimoxazole, consider alternative therapy.
Chlorpropamide
Adverse Effect: enhanced hypoglycemic effects Clinical Management: Avoid the use of Chlorpropamide in patients who are taking Chlorpropamide . If concomitant therapy is required, closely monitor blood glucose. Emergency treatment of a hypoglycemic episode may be required.
Dapsone
Adverse Effect: an increased risk of dapsone toxicity (hemolytic anemia, methemoglobinemia, peripheral neuropathy) or trimethoprim toxicity (bone marrow depression, thrombocytopenia, leukopenia, megaloblastic anemia) Clinical Management: Monitor dapsone toxicity or Cotrimoxazole toxicity adjust dosages or discontinue one of the drugs if necessary. This interaction may be more pronounced in AIDS patients with acute illness.
Digoxin
Adverse Effect: An increased risk of digoxin toxicity Clinical Management: In digitalized patients who receive Cotrimoxazole for seven days or longer, monitor digoxin serum concentrations and monitor the patient for signs and symptoms of digoxin toxicity (nausea, vomiting, arrhythmias). A decrease in the digoxin dose may be necessary.
Enalapril
Adverse Effect: hyperkalemia Clinical Management: Avoid the concurrent use of Enalapril and Cotrimoxazole , especially in patients predisposed to renal dysfunction, or ensure careful monitoring of serum potassium. Substitution of an alternative antihypertensive agent during acute Cotrimoxazole use should be considered.
Glibenclamide
Adverse Effect: Enhanced hypoglycemic effects Clinical Management: Avoid the use of sulfonamide antibiotics in patients who are taking Glibenclamide . If concomitant therapy is required, closely monitor blood glucose. Emergency treatment of a hypoglycemic episode may be required.
Glipizide
Adverse Effect: enhanced hypoglycemic effects Clinical Management: Avoid the use of sulfonamide antibiotics in patients who are taking Glipizide . If concomitant therapy is required, closely monitor blood glucose. Emergency treatment of a hypoglycemic episode may be required.
Lamivudine
Adverse Effect: an increased risk of lamivudine adverse effects Clinical Management: Clinicians should be aware that the combined use of cotrimoxazole and lamivudine may cause elevated lamivudine serum concentrations. Patients who are given this combination of medications should be followed for excessive adverse effects related to lamivudine (GI disturbances, headache, fatigue, myalgia, and rarely neutropenia). Adjustments in lamivudine dosing may be required.
Metformin
Adverse Effect: an increased risk of lactic acidosis Clinical Management: In patients receiving metformin and Cotrimoxazole , closely monitor serum glucose levels and metformin plasma concentrations. Metformin dose may need to be reduced.
Methotrexate
Adverse Effect: an increased risk of methotrexate toxicity (myelotoxicity, pancytopenia, megaloblastic anemia) Clinical Management: If possible, avoid concurrent administration.
Metronidazole
Adverse Effect: increased acetaldehyde plasma levels resulting in an increased risk of vomiting, flushing, headaches, tachycardia, and hypotension Clinical Management: Observe patients for disulfiram-like symptoms including vomiting, flushing, headaches, tachycardia, and hypotension. If possible, administer one or both drugs orally.
Phenindione
Adverse Effect: increased risk of bleeding Clinical Management: In patients receiving oral anticoagulant therapy, the prothrombin time ratio or international normalized ratio (INR) should be closely monitored with the addition and withdrawal of Cotrimoxazole and should be reassessed periodically during concurrent therapy.
Phenytoin
Adverse Effect: an increased risk of phenytoin toxicity (ataxia, hyperreflexia, nystagmus, tremors) Clinical Management: Monitor the patient for evidence of phenytoin toxicity such as nystagmus and ataxia if cotrimoxazole or trimethoprim is added to therapy.
Procainamide
Adverse Effect: an increased risk of procainamide toxicity (cardiac arrhythmias, hypotension, CNS depression) Clinical Management: Monitor serum procainamide and NAPA serum levels and for signs of procainamide toxicity (cardiac arrhythmias, hypotension, CNS depression). Dosage adjustments needed.
Pyrimethamine
Adverse Effect: an increased risk of megaloblastic anemia and pancytopenia Clinical Management: Avoid giving cotrimoxazole (sulfamethoxazole/trimethoprim) and pyrimethamine concomitantly. Should it become clinically necessary to coadminister these agents, aggressively monitor complete blood counts and observe the patient for bruising and excessive bleeding.
Tolbutamide
Adverse Effect: Enhanced hypoglycemic effects Clinical Management: Avoid the use of sulfonamide antibiotics and trimethoprim in patients who are taking Tolbutamide . If concomitant therapy is required, closely monitor blood glucose. Emergency treatment of a hypoglycemic episode may be required.
Warfarin
Adverse Effect: increased risk of bleeding Clinical Management: In patients receiving Warfarin , the prothrombin time ratio or international normalized ratio (INR) should be closely monitored with the addition and withdrawal of Cotrimoxazole and should be reassessed periodically during concurrent therapy.
Zidovudine
Adverse Effect: Increased serum concentrations of zidovudine Clinical Management: Clinicians should be aware that the combined use of cotrimoxazole and zidovudine may cause elevated zidovudine serum concentrations. Patients who are given this combination of medications should be followed for excessive adverse effects related to zidovudine (GI disturbances, headache, fatigue). |