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pyrimethamine (Rx)Brand and Other Names:Daraprim

 
 
 

Dosing & Uses

AdultPediatric

Dosage Forms & Strengths

tablet

  • 25mg
more...

Toxoplasmosis

50-75 mg qD PO for 1-3 weeks, THEN

25-37.5 mg qD PO for 4-5 weeks

P jiroveci Pneumonia (Off-label)

Prophylaxis p P jiroveci pneumonia (formerly Pneumocystis pneumonia); administer with dapsone

50-75 mg PO once/week

Tay-Sachs & Sandhoff Disease (Orphan)

Treatment of GM-2 gangliosidoses (Tay-Sachs disease and Sandhoff disease)

Orphan indication sponsor

  • ExSAR Corporation; 11 Deer Park Drive; Monmouth Junction, NJ 08852

Other Indications & Uses

Treatment & prevention of toxoplasmosis (with sulfadiazine, clindamycin, or atovaquone); malaria

Off-label: prophylaxis of P. jiroveci pneumonia (with dapsone), isosporiasis

Dosage Forms & Strengths

tablet

  • 25mg
more...

>2 Months Old

Congenital Toxoplasmosis

  • Loading dose: 2 mg/kg/day divided q12hr PO for 2 days 
  • Maintenance.: First 2-6 months old: 1 mg/kg PO qD for 2-6 months old; THEN remainder of 12 months old; 1 mg/kg PO 3 times/week

Toxoplasmosis

  • Loading dose: 2 mg/kg/d divided q12hr PO for 3 days
  • Maintenance: 1 mg/kg PO qD for 4 weeks

< 2 months old: Safety and efficacy not established

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Interactions

Interaction Checker

pyrimethamine and

No Results

     
     activity indicator 
    No Interactions Found
    Interactions Found

    Contraindicated

      Serious - Use Alternative

        Significant - Monitor Closely

          Minor

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            Adverse Effects

            Frequency Not Defined

            Abdominal cramps

            Abnormal skin pigmentation

            Anaphylaxis

            Anorexia

            Arrhythmias (large doses)

            Atrophic glossitis

            Depression

            Fever

            Insomnia

            Lightheadedness

            Malaise

            Seizures

            Dermatitis

            Erythema multiforme

            Rash

            Stevens-Johnson syndrome

            Vomiting

            Diarrhea

            Xerostomia

            Megaloblastic anemia

            Leukopenia

            Pancytopenia

            Thrombocytopenia

            Pulmonary eosinophilia

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            Warnings

            Contraindications

            Hypersensitivity

            Megaloblastic or folate-deficiency anemia

            Severe renal dz

            Breastfeeding

            Cautions

            Hepatic/renal dz, anemia, myelosuppression, epilepsy

            No longer recommended for malaria prevention or acute Tx if used alone

            Use w/ leucovorin, esp. at high doses

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            Pregnancy & Lactation

            Pregnancy Category: C

            Lactation: enters breast milk, do not nurse

            Pregnancy Categories

            A:Generally acceptable. Controlled studies in pregnant women show no evidence of fetal risk.

            B:May be acceptable. Either animal studies show no risk but human studies not available or animal studies showed minor risks and human studies done and showed no risk.

            C:Use with caution if benefits outweigh risks. Animal studies show risk and human studies not available or neither animal nor human studies done.

            D:Use in LIFE-THREATENING emergencies when no safer drug available. Positive evidence of human fetal risk.

            X:Do not use in pregnancy. Risks involved outweigh potential benefits. Safer alternatives exist.

            NA:Information not available.

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            Pharmacology

            Onset: ~1 hr

            Absorption: well absorbed

            Distribution: widely, mainly in blood cells, kidneys, lungs, liver, & spleen; crosses into CSF; crosses placenta; enters breast milk

            Protein Bound: 80-87%

            Metabolism: hepatic

            Half-life elimination: 80-95 hr

            Peak Plasma Time: 1.5-8 hr

            Excretion: urine (20-30% as unchanged drug)

            Mechanism of Action

            Folic acid antagonist

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            Images

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            Formulary

            FormularyPatient Discounts

            To view formulary information first create a list of plans. Your list will be saved and can be edited at any time.

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            The above information is provided for general informational and educational purposes only. Individual plans may vary and formulary information changes. Contact the applicable plan provider for the most current information.

            Tier Description
            1 This drug is available at the lowest co-pay. Most commonly, these are generic drugs.
            2 This drug is available at a middle level co-pay. Most commonly, these are "preferred" (on formulary) brand drugs.
            3 This drug is available at a higher level co-pay. Most commonly, these are "non-preferred" brand drugs.
            4 This drug is available at a higher level co-pay. Most commonly, these are "non-preferred" brand drugs or specialty prescription products.
            5 This drug is available at a higher level co-pay. Most commonly, these are "non-preferred" brand drugs or specialty prescription products.
            6 This drug is available at a higher level co-pay. Most commonly, these are "non-preferred" brand drugs or specialty prescription products.
            NC NOT COVERED – Drugs that are not covered by the plan.
            Code Definition
            PA Prior Authorization
            Drugs that require prior authorization. This restriction requires that specific clinical criteria be met prior to the approval of the prescription.
            QL Quantity Limits
            Drugs that have quantity limits associated with each prescription. This restriction typically limits the quantity of the drug that will be covered.
            ST Step Therapy
            Drugs that have step therapy associated with each prescription. This restriction typically requires that certain criteria be met prior to approval for the prescription.
            OR Other Restrictions
            Drugs that have restrictions other than prior authorization, quantity limits, and step therapy associated with each prescription.
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