Nitrofurantoin
Trade names:
Furadantin, Macrodantin
Dosage
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Adult: PO 50-100mg qid with meals and HS.
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Child greater than 1 years of age: PO 1.25-1.75
mg/kg/d divided in 4 doses. Maximum dose 7mg/kg/d
What is it
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Urinary anti-infective- inhibits bacterial
enzymes and metabolism
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Treats many gram-positive and gram-negative rods
which include E.coli, Neisseria, streptococci, Staphyloccocus aureus.
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Treats acute and chronic urinary tract
infections
Pharmacokinetics
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Well absorbed through GI tract- should be taken
with food to decrease GI upset.
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Avoid taking antacids at same time as these
decrease absorption of drug.
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Short half life of 20 minutes
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Excretion occurs in urine as well as small
amounts of bile
Pharmacodynamics
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Low doses used for prophylactic use=bacteriostatic
effect
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High doses used for acute infections=bactericidal
effect
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Onset and duration of action is unknown
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Peak occurs within 30 minutes
Assessment
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Obtain urine culture and sensitivity prior to beginning
of antibiotic
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Assess renal and hepatic function
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Obtain urine pH, desired is < 5.5 to maximum effectiveness
of drug
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Monitor urine output and specific gravity
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Monitor for side effects which include anorexia,
nausea, discoloration of urine to a brown/rust color, diarrhea, rash, pruritic,
dizziness, headache, drowsiness
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Monitor and assess for adverse reactions which
include peripheral neuropathy, super infections (such as stomatitis, genital
discharge or itching), hemolytic anemia, agranulocytosis. Life threatening
reactions include anaphylaxis, hepatoxicity and Steven Johnson syndrome.
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Known contraindications: moderate to severe
renal impairment, oliguria, anuria, creatine clearance <40ml/min, infants
less than 1 year of age, term pregnancy (this drug is a category B), lactation
with infant suspected of having G-6-PD deficiencies
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Known cautions in administration of drug include
Vitamin B deficiency, electrolyte imbalances, and diabetes mellitus.
Teaching to patient
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Do not crush or open capsules
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Drug can stain teeth so should rinse mouth after
administration
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Shake suspension prior to administration
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Keep at room temperature
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Patient should not operate motor vehicle or
machinery while on medication, as medication can make one drowsy
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Instruct to report S&S of super infection
such as white covering of the tongue, anogenital itching or discharge
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Should avoid taking drug with antacids and probenecid
as this decreases effectiveness of drug.
There are two forms of nitrofurantoin. Macrodantin, which is given 4 x day and Macrobid, which is given twice a day. It is not recommended to use for a CrCl < 60 ml/min.
ReplyDeletewhat are the standard dosing for both macrobid and macrodantin if the administrations differ?
ReplyDeleteI also found Furadantin as part of this medication group, what is the standard dosing and amount? thank you!
ReplyDeleteMacrobid is 100mg bid, macrodantin is usually 50mg mg qid. Furadantin is the oral suspension (50-100mg qid).
ReplyDelete