Nitrofurantoin excretion in human milk.
Six lactating white healthy women (26-36 years old, weighing 45-58 kg) were treated with 50 mg nitrofurantoin tablets, a urinary antiseptic. They received either 50 mg (group I; n = 3) or 100 mg (group II; n = 3) 3 times a day (09.00, 16.00, 19.00 h) for 24 h, 2-5 days after the delivery of a full-term neonate. The study was performed on the 4th dose at 09.00 h just before breakfast. Milk samples were collected before, 3 and 6 h after the nitrofurantoin administration with an Egnell SMB breast pump. The complete milk samples were collected from each breast, and pooled. 5 ml venous blood samples were drawn before, 1, 2, 3 and 6 h after nitrofurantoin administration. Plasma and milk nitrofurantoin concentrations were measured by HPLC. Apparent elimination half-life and apparent plasma clearance were the same in both groups, 0.8 +/- 0.09 h and 27.6 +/- 5.57 l/h, respectively. Nitrofurantoin was not detectable in the milk just before the 4th administration. The amount excreted in the milk within 6 h after nitrofurantoin administration was 22-57 micrograms (I) and 61-284 micrograms (II) which represents 0.05-0.11% (I) and 0.06-0.28 (II) of the nitrofurantoin dose. The nitrofurantoin concentration ratio of the breast milk to the plasma collected at 3 h was 2.2 +/- 1.2 (I) and 2.3 +/- 1.6 (II). These results show that nitrofurantoin excretion in human milk is low: below 0.12 (I) and 0.29% (II). It suggested that breast-fed newborn infants from mothers treated with nitrofurantoin would be exposed to small amounts of drug.(ABSTRACT TRUNCATED AT 250 WORDS)
Pons
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G
Département de Pharmacologie Clinique Périnatale et Pédiatrique, Hôpital Saint-Vincent-de-Paul, Paris, France.
Rey
E
E
Richard
M O
MO
Vauzelle
F
F
Francoual
C
C
Moran
C
C
d'Athis
P
P
Badoual
J
J
Olive
G
G
D000328:Adult; D002851:Chromatography, High Pressure Liquid; D005260:Female; D006207:Half-Life; D006801:Humans; D007774:Lactation; D008895:Milk, Human / Q000378:metabolism*; D009582:Nitrofurantoin / Q000493:pharmacokinetics*; D011247:Pregnancy
D009582:Nitrofurantoin