Complete adverse effect profile including incidence rates and management
Important Safety Information
This is not a complete list of all possible side effects. Contact your healthcare provider if you experience any unexpected symptoms. For serious or life-threatening side effects, seek emergency medical attention immediately.
ADVERSE REACTIONS Hypersensitivity reactions, occasionally severe (such as Stevens-Johnson syndrome, toxic epidermal necrolysis, erythema multiforme, and anaphylaxis), and hyperphenylalaninemia, can occur particularly when pyrimethamine is administered concomitantly with a sulfonamide.
Consult the complete prescribing information for the relevant sulfonamide for sulfonamide-associated adverse events.
With doses of pyrimethamine used for the treatment of toxoplasmosis, anorexia and vomiting may occur.
Vomiting may be minimized by giving the medication with meals;
it usually disappears promptly upon reduction of dosage.
Doses used in toxoplasmosis may produce megaloblastic anemia, leukopenia, thrombocytopenia, pancytopenia, neutropenia, atrophic glossitis, hematuria, and disorders of cardiac rhythm.
Hematologic effects, however, may also occur at low doses in certain individuals (see PRECAUTIONS ;
Pulmonary eosinophilia has been reported rarely.
To report SUSPECTED ADVERSE EVENTS, contact Teva at 1-888-838-2872 or FDA at 1-800-FDA-1088 or http://www.fda.gov/medwatch for voluntary reporting of adverse reactions.
WARNINGS The dosage of pyrimethamine required for the treatment of toxoplasmosis has a narrow therapeutic window .
If signs of folate deficiency develop (see ADVERSE REACTIONS ), reduce the dosage or discontinue the drug according to the response of the patient.
Folinic acid (leucovorin) should be administered in a dosage of 5 to 15 mg daily (orally, intravenous, or intramuscular) until normal hematopoiesis is restored.
Data in 2 humans indicate that pyrimethamine may be carcinogenic;
a 51-year-old female who developed chronic granulocytic leukemia after taking pyrimethamine for 2 years for toxoplasmosis 3 and a 56-year-old patient who developed reticulum cell sarcoma after 14 months of pyrimethamine for toxoplasmosis.
Like all medications, Pyrimethamine can cause side effects. However, not everyone who takes this medication will experience them. Many side effects are dose-dependent and may improve as your body adjusts to the medication. Others may require dose adjustment or medical attention.
Contact your healthcare provider promptly if you experience:
Seek immediate emergency medical care if you experience signs of: