What to expect from metformin for PCOS

Metformin changes how the body responds to insulin and reduces the amount of glucose made by the liver. In PCOS, this may support more regular ovulation and menstrual cycles for some people. It is not a hormone and does not remove every feature of PCOS. It may be prescribed alongside nutrition, movement, fertility care or other medicines, depending on your goals.

Nausea, loose stools, stomach discomfort or a metallic taste can occur, especially after starting or increasing the dose. These effects often ease as the body adjusts. Extended-release tablets may be an option for some people.

Take metformin exactly as prescribed, with a meal if advised, and swallow extended-release tablets whole. Do not change the dose or stop suddenly without discussing it with your prescriber. Keep follow-up appointments so kidney function, glucose-related results and symptoms can be reviewed. Tell the clinician about pregnancy, plans to conceive, kidney or liver problems, heavy alcohol use, and every medicine or supplement you take.

Contact your care team if vomiting or diarrhoea prevents you from drinking, side effects remain difficult, or your periods become unexpectedly heavy or prolonged. Seek urgent help for severe weakness, unusual sleepiness, trouble breathing, fainting or severe abdominal discomfort, particularly during an illness causing dehydration.

Ask which formulation and dose fit your symptoms, when to review your cycle or glucose goals, what to do if you miss a dose, and whether the plan changes if you become pregnant or need a procedure.