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Macrobid
nitrofurantoin
Adult Dosing .
Dosage forms: ER CAP: 100 mg
UTI tx, uncomplicated
- [100 mg PO q12h x5 days]
- Info: for cystitis; refer to IDSA guidelines; give w/ food
renal dosing
- [see below]
- CrCl <60: contraindicated per pkg insert; Alt: not defined, caution advised if CrCl 30-60
- HD/PD: avoid use
hepatic dosing
- [not defined]
Peds Dosing .
- Dosage forms: ER CAP: 100 mg
UTI tx, uncomplicated
- [>12 yo]
- Dose: 100 mg PO q12h x5 days; Info: for cystitis; refer to IDSA guidelines; give w/ food
renal dosing
- [see below]
- CrCl <60: contraindicated
- HD/PD: avoid use
hepatic dosing
- [not defined]
Contraindications / Cautions .
- hypersensitivity to drug or ingredient
- hepatic impairment hx, nitrofurantoin-associated
- cholestatic jaundice hx, nitrofurantoin-associated
- pts <1 mo
- CrCl <60 (peds pts)
- oliguria
- anuria
- pregnancy at 38-42 wk gestation
- labor and delivery
- breastfeeding of infants <1 mo w/ hyperbilirubinemia
- breastfeeding of infants w/ G6PD deficiency
- caution: pregnancy 1st trimester
- caution: G6PD deficiency
- caution: long-term use
- caution: electrolyte abnormalities
- caution: renal impairment
- caution: peripheral neuropathy
- caution: anemia
- caution: diabetes mellitus
- caution: abx-associated colitis hx, recent
Drug Interactions .
Overview
nitrofurantoin
urinary antiseptic
- alters GI flora
- impairs immunomodulatory bacterial infective agent
- methemoglobinemia
Contraindicated
- lidocaine topical
- prilocaine topical
Avoid/Use Alternative
- cholera vaccine, live
- fecal microbiota, live
- methotrexate
- typhoid vaccine, live
Monitor/Modify Tx
- flutamide
- nitric oxide
- nitrite
- warfarin
Caution Advised
- articaine
- benzocaine topical
- bupivacaine
- bupivacaine liposomal
- butamben
- chloroprocaine
- dapsone
- dapsone topical
- isosorbide dinitrate
- isosorbide mononitrate
- lactulose
- lidocaine
- mepivacaine
- metoclopramide
- nitroglycerin
- nitroprusside
- primaquine
- probenecid
- procaine
- rasburicase
- resorcinol topical
- ropivacaine
- sodium picosulfate
- sulfadiazine
- sulfamethoxazole
- sulfasalazine
- tafenoquine
- tetracaine
Adverse Reactions .
Serious Reactions
- peripheral neuropathy
- hemolytic anemia
- anemia, megaloblastic
- aplastic anemia
- agranulocytosis
- leukopenia
- thrombocytopenia
- pancreatitis
- hepatitis
- cholestatic jaundice
- hepatic necrosis
- pulmonary hypersensitivity
- pneumonitis, interstitial
- pulmonary fibrosis
- cyanosis
- ECG abnormalities
- C. difficile-assoc. diarrhea
- optic neuritis
- superinfection
- pseudotumor cerebri
- bulging fontanelles (infants)
- psychosis
- hypersensitivity rxn
- anaphylaxis
- Stevens-Johnson syndrome
- exfoliative dermatitis
- erythema multiforme
- lupus erythematosus
- vasculitis
Common Reactions
- nausea
- vomiting
- anorexia
- abdominal pain
- diarrhea
- flatulence
- asthenia
- vertigo
- nystagmus
- dizziness
- headache
- drowsiness
- confusion
- depression
- alopecia
- urine discoloration, yellow-brown
- sialadenitis
- fever
- rash
- pruritus
- urticaria
- arthralgia
- myalgia
- rigors
Safety/Monitoring .
Monitoring Parameters
BUN/Cr at baseline, then if elderly or long-term tx cont. periodically; LFTs
Look/Sound-Alike Drug Names
Macrobid confused with: Macrodantin; Micro-K; Mucobid LA; Nitro-Bid
nitrofurantoin confused with: Neurontin; nitrofurazone; nitroglycerin
Pregnancy/Lactation .
Pregnancy
Clinical Summary
contraindicated at 38-42 wk gestation, weigh risk/benefit in 1st trimester, otherwise may use during pregnancy; possible risk of teratogenicity and hemolytic anemia based on conflicting human data; dose-dependent risk of teratogenicity based on animal data at 50x and 68x recommended human dose
Lactation
Clinical Summary
avoid use while breastfeeding infant w/ G6PD deficiency or infant <1 mo w/ hyperbilirubinemia, otherwise may use while breastfeeding; possible risk of infant diarrhea and decr. milk production based on limited human data
Pharmacology .
Metabolism: liver; CYP450: unknown
Excretion: urine primarily (30-40% unchanged), bile; Half-life: 45-60min
Subclass: Antiseptics, Urinary
Mechanism of Action
inhibits DNA, RNA, protein, and cell wall synthesis (imidazolidinedione)
Formulary .
No Formulary Selected
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