Metformin

Question 1

Class?

Answer 1

Biguanide anti diabetic

Question 2

Indication?

Answer 2

• type 2 diabetes

- anovulatory infertility due to polycystic ovary syndrome (under specialist supervision)

Question 3

A/Es?

Answer 3

• malabsorption of vitamin B12
• nausea, vomiting, diarrhoea
• anorexia
• rash

Rare
> lactic acidosis
- rare, but often fatal
- early symptoms include anorexia, nausea, vomiting, abdominal pain, cramps, malaise and weight loss.

> acute hepatitis

Question 4

Dose?

Answer 4

Immediate-release tablet:

• 500mg to 1g d (1/2 doses)
• max 3g d (3 doses)

Controlled-release tablet:
500mg to 2g d

Question 5

Counseling?

Answer 5

• This medicine is best taken with the evening meal;
do not take a dose if you skip a meal
• It is common to experience an upset stomach
(e.g. nausea, loss of appetite, diarrhoea) when you first start taking this medicine; these side effects often settle down or go away with continued use.
• Your doctor may recommend that you start with a low dose and slowly increase.
• limit the amount of alcohol you consume. Drinking alcohol can affect control of your diabetes. It can also increase the risk of serious side effects. Have something to eat when you drink alcohol.

Combination with glibenclamide:
Make sure that you, and your friends and family, know how to recognise and treat hypoglycaemia (low blood glucose); ask your doctor or diabetes educator if you are unsure.