Pyridoxine for nausea and vomiting of pregnancy: A randomized, double-blind, placebo-controlled trial

Our purpose was to determine the effectiveness of pyridoxine for nausea and vomiting of pregnancy.During an 11-month period 342 women who first attended Chiang Mai University Hospital antenatal clinic at < or = 17 weeks' gestation were randomized to received either oral pyridoxine hydrochloride, 30 mg per day, or placebo in a double-blind fashion. Patients graded the severity of their nausea by a visual analog scale and recorded the number of vomiting episodes over the previous 24 hours before treatment and again during 5 consecutive days on treatment.There was a significant decrease in the mean of posttherapy minus baseline nausea scores in the pyridoxine compared with that in the placebo group (t test, p = 0.0008). There was also a greater reduction in the mean number of vomiting episodes, but the differences did not reach statistical significance (p = 0.0552).Pyridoxine is effective in relieving the severity of nausea in early pregnancy.