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trimethoprim (Rx)Brand and Other Names:Primsol, Proloprim, more...TMP

 
 
 

Dosing & Uses

AdultPediatric

Dosage Forms & Strengths

oral solution

  • 50mg/5mL

tablets

  • 100mg
more...

Susceptible Infections

100 mg PO q12hr

Renal Impairment

CrCl 15-30 mL/min: 50 mg q12hr

CrCl <15 mL/min: 100 mg q24hr or avoid use

Other Information

See also combo with sulfamethoxazole (Cotrim/Bactrim/Septra/Sulfatrim)

Available also as a combo with sulfadiazine (Coptin) in Canada

Other Indications and Uses

UTI caused by E. coli, Enterobacter spp., K. pneumoniae, P. mirabilis, coagulase-neg Staphylococcus spp.

<12 years old: safety and efficacy not established

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Interactions

Interaction Checker

trimethoprim 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

            Aseptic meningitis

            Fever

            Maculopapular rash (3-7% at 200 mg/day; incidence higher with larger daily doses)

            Erythema multiforme

            Exfoliative dermatitis

            Pruritus (common)

            Phototoxic skin eruptions

            Stevens-Johnson syndrome

            Toxic epidermal necrolysis

            Hyperkalemia

            Hyponatremia

            Epigastric distress

            Glossitis

            Nausea

            Vomiting

            Leukopenia

            Megaloblastic anemia

            Methemoglobinemia

            Neutropenia

            Thrombocytopenia

            Liver enzyme elevation

            Cholestatic jaundice

            BUN and creatinine increased

            Anaphylaxis

            Hypersensitivity reactions

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            Warnings

            Contraindications

            Hypersensitivity

            Megaloblastic anemia due to folate deficiency

            Cautions

            Decreases urinary potassium excretion; may cause hyperkalemia, particularly with high doses, renal insufficiency, or when combined with other drugs that cause hyperkalemia

            Large doses or long term therapy may interfere with hematopoiesis; monitor for signs/symptoms of hematologic disorders

            Prolonged use may cause fungal or bacterial superinfection, including clostridium difficile-associated diarrhea and pseudomembranous colitis; may occur >2 months postantibiotic treatment

            Hypersensitivity reactions reported

            Use caution in patients with renal or hepatic impairment

            Use caution in patients with potential for folate deficiency, including malnourished, chronic anticonvulsant therapy, or elderly; folates may be administered concomitantly without interfering with antibacterial action of trimethoprim

            Some dosage forms may contain benzyl alcohol and derivatives; avoid in neonates

            Not indicated for prophylactic or prolonged administration in otitis media at any age

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            Pregnancy & Lactation

            Pregnancy Category: C

            Lactation: enters breast milk

            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

            Absorption: readily and extensive

            Distribution: widely into body tissues and fluids (middle ear, prostate, bile, aqueous humor, CSF); crosses placenta; enters breast milk

            Protein binding: 42-46%

            Half-life elimination: 8-14 hr; prolonged in renal impairment

            Time to peak, serum: 1-4 hr

            Metabolism: partially hepatic

            Excretion: urine (60-80%) as unchanged drug

            Mechanism of Action

            Inhibits dihydrofolate reductase, which in turn inhibits folic acid reduction to tetrahydrofolate, causing inhibition of microorganism growth

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            Images

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            Formulary

            FormularyPatient Discounts

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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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