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nitrofurantoin (Rx)Brand and Other Names:Macrobid, Macrodantin, more...Furadantin

 
 
 

Dosing & Uses

AdultPediatric

Dosage Forms & Strengths

capsule, macrocrystals

  • 25mg
  • 50mg
  • 100mg

capsule, monohydrate/macrocystals

  • 100 mg

oral suspension

  • 25mg/5mL
more...

Urinary Tract Infection

Susceptible strains of Escherichia coli, Enterobacter spp, Klebsiella spp, Staphylococcus aureus, and S saprophyticus

Macrocrystals (Macrodantin, Furadantin, and equivalents): 50-100 mg PO q6hr for 7 days or for 3 days after obtaining sterile urine

Monohydrate/macrocrystals (Macrobid and equivalents): 100 mg PO q12hr for 7 days or for 3 days after obtaining sterile urine

Long-term prophylaxis/suppression: 50-100 mg macrocrystals PO HS for up to 12 months

Dosing Considerations

Avoid for long-term UTI suppression; possible pulmonary toxicity; safer alternatives are available

Not drug of choice in elderly because of unfavorable side-effect profile

Loses effectiveness in patients with CrCl <60 mL/min due to inadequate urine concentration (Beers criteria)

Monitor renal function; renally excreted; decreased renal function more likely in elderly

Monitor liver function and possible pulmonary reactions

Take with food or milk

Dual release macrocrystals indicated only for patients >12 years for acute UTIs (cystitis) caused by E coli or S saprophyticus

Dosage Forms & Strengths

capsule, macrocrystals

  • 25mg
  • 50mg
  • 100mg

capsule, monohydrate/macrocrystals

  • 100 mg

oral suspension

  • 25mg/5mL
more...

Urinary Tract Infection

>1 month

  • 5-7 mg/kg/day PO divided q6hr for 7 days
  • UTI prophylaxis: 1-2 mg/kg PO qHS or 2 divided doses

>12 years

  • Macrocrystals (Macrodantin, Furadantin, and equivalents): 50-100 mg PO q6hr for 7 days or for 3 days after obtaining sterile urine
  • Monohydrate/macrocrystals (Macrobid and equivalents): 100 mg PO q12hr for 7 days or for 3 days after obtaining sterile urine
  • Long-term prophylaxis/suppression: 50-100 mg macrocrystals PO HS for up to 12 months

Dosing Considerations

Avoid for long-term UTI suppression; possible pulmonary toxicity; safer alternatives are available

Loses effectiveness in patients with CrCl <60 mL/min due to inadequate urine concentration (Beers criteria)

Monitor renal function; renally excreted; decreased renal function more likely in elderly

Monitor liver function

Take with food or milk

Dual release macrocrystals indicated only for patients >12 years for acute UTIs (cystitis) caused by E coli or S saprophyticus

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Interactions

Interaction Checker

nitrofurantoin 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

            Anorexia

            Arthralgia

            Chest pains

            Chills

            Cough

            Clostridium difficile colitis

            Cyanosis secondary to methemoglobinemia

            Diarrhea

            Dizziness

            Drowsiness

            Dyspnea

            Exfoliative dermatitis

            Fatigue

            Fever

            Flatulence

            Headache

            Hemolytic anemia

            Hepatitis

            Increased LFTs

            Itching

            Nausea

            Numbness

            Paresthesia

            Rash

            Sore throat

            Stomach upset

            Vomiting

            Weakness

            Urine discoloration

            Vasculitis

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            Warnings

            Contraindications

            Renal failure (anuria, oliguria, or CrCl <60 mL/min)

            Pregnancy at term (38-42 weeks of gestation)

            History of hepatic dysfunction/cholestatic jaundice with nitrofurantoin

            Neonates (<28 days)

            Hypersensitivity

            Cautions

            Caution in patients with G6PD deficiency (may increase risk for hemolytic anemia)

            Avoid long-term use in the elderly (may increase risk for pulmonary toxicity)

            Renal impairment

            Discontinue if paresthesia or hemolysis develop

            Risk of occasional hepatotoxicity and pulmonary toxicity

            Protect from light

            Peripheral neuropathy may occur; risk may increase in patients diagnosed with anemia, diabetes, vitamin B deficiency, or electrolyte imbalance (use caution)

            Acute/chronic pulmonary reactions (eg., cough, interstitial pneumonitis or fibrosis) reported

            Bacterial superinfections may occur with prolonged treatment

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            Pregnancy & Lactation

            Pregnancy category: B; contraindicated at term

            Crosses placenta, but not well distributed

            Lactation: Enters breast milk; discontinue drug or 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.

            more...
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            Pharmacology

            Mechanism of Action

            Inactivates or alters bacterial ribosomal proteins and other macromolecules that may interfere with metabolism and cell-wall synthesis

            Absorption

            Well absorbed; macrocrystalline form absorbed more slowly due to slower dissolution (causes less GI distress)

            Bioavailability: Increased with food

            Distribution

            Crosses placenta, but not well distributed

            Protein bound: Approximately 60-90%

            Vd: 0.8 L/kg

            Metabolism

            Reduced by bacterial flavoproteins to reactive intermediates

            Body tissues (except plasma) metabolize 60% of drug to inactive metabolites

            Elimination

            Half-life: 20-60 min; prolonged with renal impairment

            Excretion: Urine (40%); feces (small amounts)

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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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