A randomized comparison of ginger and vitamin B6 in the treatment of nausea and vomiting of pregnancy

Abstract

Objective: To compare the efficacy of ginger to vitamin B6 in the treatment of nausea and vomiting of pregnancy.

Study design: A randomized double-blind controlled trial.

Setting: The Department of Obstetrics and Gynecology, Bangkok Metropolitan Administration Medical College and Vajira Hospital.

Subjects: Women with nausea and vomiting of pregnancy at or before 16 weeks of gestation, who attended the antenatal care clinic. The subjects requested anti-emetics, had no medical complications, non-hospitalized and were able to attend a one week follow-up visit. From November, 1999 to November 2000, 138 women participated and gave consent for the study.

Method: The subjects were randomly allocated into two groups to take either 500 mg of ginger orally or an identical 10 mg of vitamin B6 one capsule three times daily for three days. Subjects graded the severity of their nausea using visual analogue scales before treatment and recorded the number of vomiting episodes in the previous 24 hours and again during three consecutive days of treatment.

Main outcome measures: The change of nausea scores and the number of vomiting episodes during three days of treatment.

Results: The 64 subjects in each group remained in the study. The demographic data were comparable in both groups. The ginger and vitamin B6 significantly reduced the nausea scores from 5.0 (SD, 1.99) to 3.6 (SD, 2.48) and 5.3 (SD, 2.08) to 3.3 (SD, 2.07) respectively, with p < 0.001. The mean score change after treatment with ginger was 1.4 (2.21), less than with vitamin B6, which was 2.0 (2.19) but with no statistically significant difference (95% CI -1.4 to 0.2, p = 0.136). The ginger and vitamin B6 also significantly reduced the number of vomiting episodes from 1.9 (2.06) to 1.2 (1.75) and 1.7 (1.81) to 1.2 (1.50) respectively, with p < 0.01. The mean number change after treatment with ginger was 0.7 (2.18), more than with vitamin B6, which was 0.5 (1.44) but with no statistically significant difference, (p = 0.498). There were some minor side effects in both groups such as sedation (26.6% vs 32.8%, p = 0.439), and heartburn (9.4% vs 6.3%, p = 0.510), a non-significant difference.

Conclusion: The nausea score and the number of vomiting episodes were significantly reduced following ginger and vitamin B6 therapy. Comparing the efficacy, there was no significant difference between ginger and vitamin B6 for the treatment of nausea and vomiting during pregnancy.