Pregnancy outcome following use of large doses of vitamin B6 in the first trimester

The Motherisk Program, Division of Clinical Pharmacology/Toxicology, Hospital for Sick Children, University of Toronto, Ontario, Canada.
Journal of Obstetrics and Gynaecology (Impact Factor: 0.55). 12/2006; 26(8):749-51. DOI: 10.1080/01443610600955826
Source: PubMed


Vitamin B6 is often prescribed for the treatment of nausea and vomiting of pregnancy (NVP), at much higher doses than initially recommended. Large doses of vitamin B6 have been associated with cases of neuropathy. We set out to assess whether higher than standard doses of vitamin B6 during the first trimester of pregnancy were associated with a risk of maternal adverse events, major malformations, miscarriages or low birth weight. This was a prospective comparative observational study. The study group included women who were exposed to >50 mg/day of vitamin B6 during the first trimester; the control group included pregnant women with a non-teratogen exposure. A total of 192 pregnancies were followed-up. The mean dose of B6 used in the study group was 132.3 mg/day (median 110 mg/day, range 50 - 510 mg/day), for a mean period of 9 +/- 4.2 weeks. In this group (n = 96), there were 91 live births, one major malformation and the mean birth weight was 3,542 +/- 512 g. There were no statistical differences in the study endpoints between the vitamin B6 and the control groups. Within the limits of our sample size, higher than standard doses of vitamin B6 do not appear to be associated with an increased risk for major malformations.

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    • "In 1983 the manufacturer voluntarily removed the drug from the market due to litigations and false allegations regarding teratogenic effects. Consequently, there was a 2–3-fold increase in the rate of hospitalization due to NVP.9,35,36 Many case control and cohort studies, with over 170,000 exposures have demonstrated the safety of the combination of doxylamine and pyridoxine, and although it is no longer commercially available in the United States, many compounding pharmacies will prepare the combination on request.7 Women will also take a combination of doxylamine succinate (ie, Unisom®) and a vitamin B6 tablet for the same effect. "
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    ABSTRACT: Nausea and vomiting of pregnancy (NVP) is a common medical condition in pregnancy with significant physical and psychological morbidity. Up to 90% of women will suffer from NVP symptoms in the first trimester of pregnancy with up to 2% developing hyperemesis gravidarum which is NVP at its worst, leading to hospitalization and even death in extreme cases. Optimal management of NVP begins with nonpharmacological approaches, use of ginger, acupressure, vitamin B6, and dietary adjustments. The positive impact of these noninvasive, inexpensive and safe methods has been demonstrated. Pharmacological treatments are available with varying effectiveness; however, the only drug marketed specifically for the treatment of NVP in pregnancy is Diclectin(®) (vitamin B6 and doxylamine). In addition, the Motherisk algorithm provides a guideline for use of safe and effective drugs for the treatment of NVP. Optimal medical management of symptoms will ensure the mental and physical wellbeing of expecting mothers and their developing babies during this often stressful and difficult time period. Dismissing NVP as an inconsequential part of pregnancy can have serious ramifications for both mother and baby.
    International Journal of Women's Health 08/2010; 2(1):241-8. DOI:10.2147/IJWH.S6794
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    • "Pyridoxine is given three times daily at a dose of 10 - 25 mg starting with a low dose that may reduce symptoms and has been proven to be more effective than placebo [13,60]. The daily dose can be increased up to 200 mg without side effects [61,62]. However, a more recent placebo-controlled trial demonstrated that a combination of oral pyridoxine and metoclopramide did not improve the vomiting frequency or the nausea score [63]. "
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    ABSTRACT: Up to 90% of pregnant women experience nausea and vomiting. When prolonged or severe, this is known as hyperemesis gravidarum (HG), which can, in individual cases, be life threatening. In this article the aetiology, diagnosis and treatment strategies will be presented based on a selective literature review. Treatment strategies range from outpatient dietary advice and antiemetic drugs to hospitalization and intravenous (IV) fluid replacement in persistent or severe cases. Alternative methods, such as acupuncture, are not yet evidence based but sometimes have a therapeutic effect. In most cases, the condition is self limiting and subsides by around 20 weeks gestation. More severe forms require medical intervention once other organic causes of nausea and vomiting have been excluded. In addition, a psychosomatic approach is often helpful. In view of its potential complexity, general practitioners and obstetricians should be well informed about HG and therapy should be multimodal.
    BMC Medicine 07/2010; 8(46):46. DOI:10.1186/1741-7015-8-46 · 7.25 Impact Factor
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    ABSTRACT: QUESTIONMy patient has severe nausea and vomiting of pregnancy (NVP). I am having difficulty treating her, as nothing she has tried so far has been really effective. I heard that there is some new information regarding the treatment of this condition.ANSWEREven a less severe case of NVP can have serious adverse effects on the quality of a woman's life, affecting her occupational, social, and domestic functioning, and her general well-being; therefore, it is very important to treat this condition appropriately and effectively. There are safe and effective treatments available. We have updated Motherisk's NVP algorithm to include recent relevant published data, and we describe some other strategies that deal with secondary symptoms related to NVP.
    Canadian family physician Medecin de famille canadien 01/2008; 53(12):2109-11. · 1.34 Impact Factor
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