Pyridoxone (vitamin B6)
Pyridoxone, otherwise known as Vitamin B6, is a vitamin which is required to maintain a healthy nervous system. It has been shown to be effective in helping nausea and vomiting in pregnancy in two randomised controlled trials against placebo (one trial at 30mgs / daily, the other at 75mgs / daily). A retrospective cohort study concluded that pyridoxine monotherapy had no increased risk for major malformations. There are no apparent side effects for doses under 50mg per day.
Current research supports a dose of 10mg 1 tablet 4 x per day.