When are these medicines likely to be used?

Type 1: As soon as this form of diabetes is diagnosed, a person will receive insulin. Occasionally this protects the few remaining beta cells and may result in a temporary remission (honeymoon period). However, this is invariably short and people with type 1 diabetes will need some form of insulin, coupled with dietary control, throughout their lives.

Type 2: In a person with impaired glucose tolerance or type 2 diabetes, the first approach to management will often be to regulate the diet and modify the life-style. A low-fat, high carbohydrate diet (coupled with reduction in calories for the overweight) will be combined with increased physical activity. If these measures prove inadequate, then medicines will be added in a cascade fashion to achieve control.

About 60-70 per cent of people with type 2 diabetes take oral medication, and rather fewer with type 1. The doctor may prescribe a medicine that stimulates insulin secretion, such as one of the sulphonylureas. In some people, especially those who are very overweight, the biguanide metformin is usually the first choice. An alpha-glucosidase inhibitor such as acarbose may also be prescribed, as this reduces the absorption of glucose in the intestines and hence its uptake into the blood.