Diabetes, once considered as a disease of the affluent west, has now emerged as a major cause of morbidity and mortality in developing countries as well. Rapid urbanisation, lack of physical exercise, obesity, high calories diet, mental tension and worries or hereditary factors, are responsible for this increase. Deficiency of insulin, (hormone produced in pancreas and responsible for sugar regulation in the body), or its absence is the root cause of diabetes which leads to increase in blood glucose. Children and young adults suffering from diabetes need only insulin for treatment as there is no insulin being produced in the body (type 1 diabetes). Middle aged or elderly patients can be tried on a schedule of diet restrictions, exercise and oral anti diabetic medicines (type II diabetes). But if blood glucose remains high persistently, they are switched over to insulin for better control. Apart from this, type 2 patients need insulin if they develop any complication of diabetes. When a diabetic woman becomes pregnant, insulin is preferred for adequately controlling the blood glucose as high blood glucose levels at this time are detrimental to the baby. Insulin is used during any major surgery or trauma in a diabetic to prevent infections. Thus, it can be seen that insulin is virtually a life line for diabetic patients. Different types of insulin are available with variation in the duration of action. Rapid acting insulins are useful for emergencies when the need is to bring down the high blood glucose immediately. They are also useful for allowing flexibility of meals. Intermediate and long acting insulins provide ease of administration as they need to be injected only once or twice in 24 hours. Insulin is always started in a low dose, which is adjusted with results of blood glucose. It always should be taken before food. This helps in preventing the post meal rise of blood glucose. Having a meal also ensures that blood glucose levels do not fall to very low levels with insulin. Between insulin injection and a meal, the time interval should not be more than 30 minutes. Regarding long term use, insulin is very safe. Occasionally, somebody can have allergy at site of injection. When used for a long time, sometimes resistance can develop to it, but this problem can be tackled by altering the type and dose of insulin. Unfortunately, insulin is available always in injection form. There are no tablets to be taken by mouth. Because one needs insulin for a lifetime, it is always better that the individual learns to inject him or herself. Injections are given subcutaneously, that is, below the superficial layers of skin and can be easily used by a person for self-injection over the thighs or forearms. Intravenous injections are used only for emergencies. Vial of insulin should be placed in a cool place at about four to eight degrees centigrade away from direct sunlight. Special syringes are available for injecting insulin which are commonly available in strengths of 40 and 100 units. Thus, once a person learns to inject insulin, he can easily use it correctly. Now prefixed insulins are available, which are very convenient. One just has to inject it without even bothering to draw a fixed amount from a vial. This has become very convenient for the user. Diabetic individuals should also be aware of symptoms of hypoglycemia (low blood glucose). If after injecting insulin, one experiences sweating, palpitations and or sudden weakness and giddiness, he should immediately eat or drink something to avoid serious hypoglycemia. Glucometers are easily available now. With them, one can monitor blood glucose levels at home and adjust dose of insulin accordingly. With correct use of insulin, regular diet and exercise every diabetic individual can maintain a good quality of life. Dr Rachna Pande, Specialist, internal medicine rachna212002@yahoo.co.uk