Gabapentin in Pregnancy and Breastfeeding

Risk Factor: CM
Class: Central nervous system drugs / Anticonvulsants

Contents of this page:
Fetal Risk Summary
Breast Feeding Summary
References
Questions and Answers

Fetal Risk Summary

Gabapentin is an anticonvulsant used as adjunctive therapy for the treatment of partial seizures in patients with epilepsy (1,2). It is not known whether gabapentin crosses the human placenta to the fetus. Because of its lack of protein binding and low molecular weight (about 171), however, transfer to the fetus should be expected.

Fetotoxicity in mice exposed during organogenesis to maternal oral doses of about 1 to 4 times the maximum recommended human dose on a mg/m2 basis (MRHD) was characterized by delayed ossification of bones in the skull, vertebrae, forelimbs, and hindlimbs (2). The no-effect dose in mice was about one-half of the MRHD. Delayed ossification was also observed in rats exposed in utero to less than 1 to 5 times the MRHD. Hydroureter or hydronephrosis was observed in rat pups exposed in utero during organogenesis and during the perinatal and postnatal periods after similar doses. The causes of the urinary tract anomalies were unclear (2). The no-effect dose in rats during organogenesis was approximately equal to the MRHD in the teratogenicity study. When compared with controls, exposure to gabapentin during organogenesis did not increase congenital malformations, other than hydroureter or hydronephrosis in rats, in mice, rats, and rabbits at 4, 5, or 8 times, respectively, the MRHD. In rabbits, doses less than about one-quarter to 8 times the MRHD caused an increased incidence of postimplantation fetal loss (2).

Only four published reports have been located that describe the human use of gabapentin during gestation. In addition, no cases of fetal or newborn adverse outcomes had been reported to the FDA through 1996 (personal communication, F. Rosa, FDA, 1996).

In a brief 1995 communication, a newborn exposed to gabapentin and carbamazepine during pregnancy had a cyclops holoprosencephaly (no nose and one eye) (3). Of the seven suspected cases of holoprosencephaly described in this report, five involved the use of carbamazepine (two cases of monotherapy and three of combined therapy). Because of the lack of family histories, an association with familial holoprosencephaly or maternal neurologic problems could not be excluded (3).

The Lamotrigine Pregnancy Registry, an ongoing project conducted by the manufacturer, was first published in January 1997 followed by interim reports with the latest release in July 2000 (4) (see Lamotrigine for consensus statement required for the use of these data) (4). One of the cases prospectively identified following 1st trimester exposure to lamotrigine (400800 mg/day during gestation) involved a 29-year-old woman who also received gabapentin (dose not specified) before and throughout pregnancy. She gave birth at 37 weeks' gestation to a male infant with skin tags on the left ear, no opening to the ear canal on the right ear, jaundice, and intermittent tremors that occurred for about 5 days after birth. No defects were observed in four other live births in which the combination of gabapentin and lamotrigine was used during pregnancy with or without other anticonvulsants (valproate, phenytoin, diazepam, and/or phenobarbital) (4).

A 1998 non-interventional observational cohort study described the outcomes of pregnancies in women who had been prescribed one or more of 34 newly marketed drugs by general practitioners in England (5). Data were obtained by questionnaires sent to the prescribing physicians one month after the expected or possible date of delivery. In 831 (78%) of the pregnancies, a newly marketed drug was thought to have been taken during the 1st trimester with birth defects noted in 14 (2.5%) singleton births of these 557 newborns (10 sets of twins). In addition, two birth defects were observed in aborted fetuses. However, few of the aborted fetuses were examined. Gabapentin was taken during the 1st trimester in 17 pregnancies. The outcomes of these pregnancies included 2 spontaneous abortions, 4 elective abortions, and 11 normal newborns (1 premature) (5). Although no congenital malformations were observed, the study lacked the sensitivity to identify minor anomalies. Late appearing major defects may also have been missed due to the timing of the questionnaires.

A 1996 review reported 16 pregnancies exposed to gabapentin from preclinical trials and postmarketing surveillance (6). The outcomes of these pregnancies included five elective abortions, one ongoing pregnancy, seven normal infants, and three infants with birth defects. No specific information was provided on the defects other than the fact that there was no pattern of malformation and all were receiving polytherapy for epilepsy (6).

In summary, the limited human data do not allow an assessment as to the safety of gabapentin in pregnancy. Because the agent is often combined with other anticonvulsants the actual cause of a defect may be obscured. Of note, no distinguishable pattern of malformations has been reported. Based on this limited evidence, if a woman's condition requires gabapentin, the benefits of therapy to her appear to outweigh the potential risks to her fetus.

Breast Feeding Summary

No reports describing the use of gabapentin during human lactation have been located. Because of its low molecular weight (about 171), transfer into milk should be expected. The effects of this exposure on a nursing infant are unknown.

References

  1. Dichter MA, Brodie MJ. New antiepileptic drugs. N Engl J Med 1996;334:158390.
  2. Product information. Neurontin. Parke-Davis, 2001.
  3. Rosa F. Holoprosencephaly and antiepileptic exposures. Teratology 1995;51:230.
  4. Lamotrigine Pregnancy Registry. Interim Report. 1 September 1992 through 31 March 2000. Glaxco Wellcome, July, 2000.
  5. Wilton LV, Pearce GL, Martin RM, Mackay FJ, Mann RD. The outcomes of pregnancy in women exposed to newly marketed drugs in general practice in England. Br J Obstet Gynaecol 1998;105:8829.
  6. Morrell MJ. The new antiepileptic drugs and women: efficacy, reproductive health, pregnancy, and fetal outcome. Epilepsia 1996;37(Suppl 6):S34S44).

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Questions and Answers

Gabapentin?, I took 3 300MG of gabapentin per doctor's order.. can anybody tell me what this drug is used for and it's side effects?? Thanks

The drug is used for seizures in pts with epilepsy. The dosing your on is a good one.
The side effects are:
Drowsiness, fatigue, dizziness, tremor, slurred speech, impaired concentration, weight gain, nausea, gastric upset, vomiting, blurred vision, rash, eczema.
Remember these are side effects that SOME ppl get not all. Talk with your doctor if you have these effects.
Cheers~!

Does anyone know how long it takes for gabapentin to start to work for sleep disorders?, I've been taking ambien for years and now it's not working so my doctor has switched me to gabapentin. I've taken it for 3 nights and I still am not sleeping, but I'm really foggy in the morning. If anyone can tell me how long it took for them, that would be sweet.

Hmm, never heard gabapentin being used for sleeping. If it does not work after a few nights call your doctors office and see about getting it changed or making a new office visit.

Is it reasonable to assume that gabapentin can cause significant drug interactions or side effects?, Gabapentin is not significantly metabolised and is mainly excreted in the urine, is known for having a relatively low side effect profile, but why would it cause a reaction in a patient being treated for neuropathic pain?

i have been taking this for years for head pain and never had any affects

how can i get Memantine and gabapentin for nystagmus eye condition?, i read on a google search the Memantine and gabapentin can help with nystagmus, can my doctor prescribe this? or how should i go about getting it... any help is great!
thanks!

First, confirm that your primary care physician has diagnosed the underlying cause of your nystagmus.

Nystagmus is a clinical finding, not a disease. There are several different potential causes and underlying diseases, some very serious.
You don't want to treat a symptom and ignore the cause.

Once the diagnosis and treatment have been addressed, if the nystagmus continues, ask your physician for a referral to a neurologist. They are best qualified to recommend treatment... and, yes, nerve modifies like Neurontin (gabapentin) may help. There are many other options.
Namenda (memantine) is still in trials for this use. It is unproven.

How long will Gabapentin stay in my system?, How long will gabapentin stay in my system?

I'm really hoping that you've taken this by prescription, if not, stop! Get help with stopping, you should be tapered off it. This stuff has some nasty side effects. As far as how long it's in your system, I think it's around 24 hours.

Does Gabapentin help with nerve pain created by have had open heart surgery when they crack your chest open?, I had open heart surgery and have a problem with numbness and sharp burning pain across my chest. It has been diagnosed as nerve pain from the nerves across my chest that were cut opening my chest to perform the bypass. I was put on Gabapentin for it and have been told that if it still exists after 1 year then it will be permanent.

im surprised they put u on gabapentin. it works on some nerves, however,gabapentin is used for epilepsy to manage seizures. another generic name for gabapentn is neurontin. ive had 7 by-passes, but they gave me hydrocodone. i also have a numness in my chest, and it is permanent. but its not life threating, just somethink we will have to live with. i had mine 7 yrs. ago. hope this helps. god bless

What exactly is Gabapentin medication used to treat, and is that the name brand or genertic id?, I saw this listed under a Bipolar site. I wondered if it was prescribed alot or very rarely. Knowledge is the key of healing the human mind and body.

Hairstylist are sharing information with the clients to better their awarness of depression and bipolar advantage of knowing the disorder.

Here is the full story on Gabapentin.
http://www.drugs.com/gabapentin.html

How doeses Gabapentin work and is it a safe drug?, It's anti-spasmodic and calms the nervous system. But is it addictive?

Gabapentin is in a class of medications called anticonvulsants. Gabapentin treats seizures by decreasing abnormal excitement in the brain. Gabapentin relieves pain by changing the way the body senses pain. I would think it poses a moderate risk of addiction since it does alter the way the body senses pain.

Can I take the drug,"GABAPENTIN" to relieve pain caused by a sciatic nerve problem?, I suffer pain from a sciatic nerve condiction. Can I take the drug,"Gabapentin" to relieve these pains?

You cannot just pop one or two and thats it. This is a drug that you need to start slowly to get up to a dosage thats determined by your dr and then if you want off of it, you have to decrease your dosage.
Do not take medications that are not over the counter unless prescribed FOR YOU by your Dr for that condition.

Gabapentin was given to a friend of mine for pain. Has anyone had a bad experience taking Gabapentin for pain, This medication was given to a friend of mine for pain.
I see the side affects of this medication can be deadly. Why in the world they prescribed that? Does anyone have any experience with this?

Consult medical practitioner only.