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When diet and exercise fail to sufficiently lower blood glucose levels in type 2 patients, the doctor may decide to add insulin, an oral sulfonylurea drug or both. However, no drug can replace diet and exercise; they are always essential.

Sulfonylurea drugs are used only for type 2 diabetes, mainly for patients whose diabetes is judged less severe. Insulin is the usual choice for advanced type 2 cases, and both drugs may be given if the illness is somewhere in between. (Patients on insulin alone often must take it several times a day; those who also take a sulfonylurea drug usually need insulin only once daily.)

These are, however, just rough rules of thumb. A patient's age, body build, lifestyle, preferences, how long he or she has had diabetes, and overall health may figure in the decision. In addition, experts disagree about whether patients are more likely to have heart attacks if treated with a sulfonylurea drug than if treated with just diet or diet and insulin.

Only one of the six sulfonylurea drugs sold in this country — tolbutamide (Orinase) — was used in the major scientific study that led to this controversy. But the other five are chemically very similar to it. FDA, therefore, requires the manufacturers of all sulfonylureas to include in the labeling and any promotional material for physicians a warning of this potential hazard.

The names of these other drugs are acetohexamide (Dymelor), chlorpropamide (Diabinese), glipizide (Glucotrol), glyburide (Diabeta and Micronase), and tolazamide (Tolinase). There are differences among them that can bear on which a doctor prescribes. For example, both tolbutamide and chlorpropamide can cause dizziness if combined with alcohol, a consideration for patients who drink.

It is not always clear whether insulin, oral medication, both, or just a more rigorous diet is best for a given type 2 patient. And some experts believe that a sulfonylurea should not be used with insulin. Patients may want to ask their doctors to explain all the options and the pros and cons of each.

Despite good treatment and control, both type 1 and type 2 patients tend to develop complications, especially as time goes on. Their impact can often be minimized or slowed by routine physician monitoring and by patients' promptly reporting even minor symptoms and changes in their well-being to the appropriate physician or other health-care professional.

Regular dental checkups are particularly important. So are periodic eye examinations by an ophthalmologist (physician eye specialist). Diabetics get cataracts and glaucoma more often than most people and also are prone to another potentially blinding disorder — diabetic retinopathy — that other people don't get. The sooner these disorders are detected, the greater are the chances of treatment's saving the patient's sight.

As Edward S. Horton, M.D., of the University of Vermont — a recent president of the American Diabetes Association — sums it up: "Diabetes can be a deadly disease. But with the help of modern medicine and their own efforts, many patients can lead long, active and relatively healthy lives."

Types of Insulin

The more than 30 insulin formulations on the U.S. market are variations of several basic types, the most commonly used of which are:

Purified Pork — pork pancreas-derived insulin that has undergone further purification

Purified Beef — beef pancreas-derived insulin that has undergone further purification

Recombinant DNA-origin (Human) — genetically engineered insulin made by a inserting the human gene for insulin production into a non-disease-producing laboratory strain of Escherichia coli bacteria or into yeast. Formulations of all insulins also vary by how quickly they act and for how long. Some formulations contain a mix of insulins that vary on these scores as well. Also, some are packaged to be used with only one manufacturer's model or models of injection or portable pump devices.

Each type of insulin has specific benefits that the doctor takes into consideration before telling the patient which insulin to take.

When insulin was first marketed in this country in the 1920s, no prescription was required because many patients did not have telephones and lived far from a doctor. FDA has allowed insulin to remain on the market OTC because it's needed by a large number of people whose lives depend on it. However, some states require a prescription for insulin and the devices used to administer it.

Diabetes patients should use only the insulin formulation their doctor recommends and should not switch formulations without their doctor's approval.

Tags: Diabetes

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FDA is A United States government body that oversees medical devices, including contact lenses, intraocular lenses, excimer lasers and eyedrops. In the US, these products must be approved by the FDA before they can be marketed.