Fishy metformin proves hard to swallow

Some patients are refusing to take metformin due to nausea caused by a reported dead fish or dirty socks odour burped up from the stomach, say US doctors. In a letter to the Annals of Internal Medicine, they say the problem can be addressed by coating the pills so they do not smell, but expressed surprise the reaction to metformin has not been previously reported. They report the case where one man who had taken brand-name metformin was switched to a generic, immediate-release version, resulting in nausea and the patient refusing to take the medication. However the symptoms went away after he took a coated, extended-release generic version. Doctors may think patients taking metformin are experiencing nausea, vomiting and flatulence as a result of the drug itself, when instead the symptoms could be caused just by the smell, the authors write. In Australia, a prospective randomised trial of weight management in overweight and obese young women has found that metformin may be effective in weight gain prevention, but lifestyle intervention was more effective than metformin in reducing body weight. However, higher attrition in the lifestyle group points towards a need for longer studies to determine the long-term sustainability and effectiveness of strategies in this group, they say....