- Differential Diagnosis
- Try building your search one term at a time, and be as specific as you can! Search term example: "chronic cough".
- Do not enter multiple findings such as "anemia, chronic cough, weight loss, vomiting" all at the same time.
- After selecting your term from the search results a list of possible diagnoses will be generated. If the list is too long, you will be able to narrow it down by entering additional terms.
- Do not enter values such as "heart rhythm 110" or "sodium 125", instead use "tachycardia" or "hyponatremia".
Drug Information for DARAPRIM (pyrimethamine) 25-mg Scored Tablets (GlaxoSmithKline): OVERDOSAGE
- CLINICAL PHARMACOLOGY
- ADVERSE REACTIONS
- HOW SUPPLIED
- Diseases/Conditions Related to DARAPRIM (pyrimethamine) 25-mg Scored Tablets (GlaxoSmithKline)
- External Links Related to DARAPRIM (pyrimethamine) 25-mg Scored Tablets (GlaxoSmithKline)
Following the ingestion of 300 mg or more of pyrimethamine, gastrointestinal and/or central nervous system signs may be present, including convulsions. The initial symptoms are usually gastrointestinal and may include abdominal pain, nausea, severe and repeated vomiting, possibly including hematemesis. Central nervous system toxicity may be manifest by initial excitability, generalized and prolonged convulsions which may be followed by respiratory depression, circulatory collapse, and death within a few hours. Neurological symptoms appear rapidly (30 minutes to 2 hours after drug ingestion), suggesting that in gross overdosage pyrimethamine has a direct toxic effect on the central nervous system.
The fatal dose is variable, with the smallest reported fatal single dose being 375 mg. There are, however, reports of pediatric patients who have recovered after taking 375 to 625 mg.
There is no specific antidote to acute pyrimethamine poisoning. In the event of overdosage, symptomatic and supportive measures should be employed. Gastric lavage is recommended and is effective if carried out very soon after drug ingestion. Parenteral diazepam may be used to control convulsions. Folinic acid should also be administered within 2 hours of drug ingestion to be most effective in counteracting the effects on the hematopoietic system (see WARNINGS). Due to the long half-life of pyrimethamine, daily monitoring of peripheral blood counts is recommended for up to several weeks after the overdose until normal hematologic values are restored.
- Drug Information Provided by National Library of Medicine (NLM).