breast feeding and gabapentin/Neurontin
Are there any studies indicating if mothers on Gabapentin can safely breast feed? the 2004 Mother's Milk book says it is a L3 without much research available. Anything new?
Below is the most current data.
Tom Hale Ph.D.
Gabapentin is an older anticonvulsant used primarily for partial (focal) seizures with or without secondary generalization. It is also used for postherpetic neuralgia or neuropathic pain. Unlike many anticonvulsants, gabapentin is almost completely excreted renally without metabolism, it does not induce hepatic enzymes and is remarkably well tolerated.[1,2,3] In a study of one breastfeeding mother who was receiving 1800 mg/d, milk levels were 11.1, 11.3, and 11.0 mg/L at 2, 4, and 8 hours respectively, following a dose of 600 mg. The milk-plasma ratio was calculated to be 0.86 and the relative infant dose was 2.34%. No adverse effects to gabapentin were noted in the infant.[4,6] In another patient receiving 2400 mg/d milk levels were 9.8, 9.0, and 7.2 mg/L at 2,4, and 8 hours respectively, after a dose of 800 mg. Using this data an infant would consume approximately 3.7% to 6.5% of the weight-adjusted maternal dose per day. No adverse events were noted in these two infants.
In another study of 5 mother-infant pairs receiving 900-3200 mg gabapentin per day, the mean milk/plasma ratio ranged from 0.7 to 1.3 from 2 weeks to 3 months postpartum. At 2-3 weeks, two of the five infants had detectable concentrations of gabapentin (1.3 and 1.5 µM) and one was undetectable. These levels were far below the normal plasma levels in the mothers (11-45 µM). Assuming a daily milk intake of 150 mL/day/kg, the infant dose of gabapentin was estimated to be 0.2-1.3 mg/kg/day, which is equivalent to 1.3-3.8% of the weight-normalized dose received by the mother. The plasma levels of gabapentin collected after 3 months of breastfeeding in another infant was 1.9 µM. The authors concluded that the plasma levels measured were low if at all detectable in the infants, and no adverse effects were reported in these infants.
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4.Hale TW, Ilett KF, Hackett P. Personal communication. 2002.
5.Ohman I, Vitols S, Tomson T. Pharmacokinetics of gabapentin during delivery, in the neonatal period, and lactation: does a fetal accumulation occur during pregnancy? Epilepsia 2005 Oct; 46(10):1621-4.
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