Medications for People with Diabetes
by Phillip Treadwell, PharmD

Many medications are now available for the treatment of diabetes. Each of these drugs has distinct advantages and disadvantages. This does not mean, however, that when properly selected, the risks outweigh the benefits. It is crucial to remember that excellent control of diabetes is much more important than avoidance of side effects when the right medicines are used. I will explain some of the advantages and disadvantages of some of the commonly used diabetes medicines. With this information, you and your physician can make the best choice for your health.

Insulin is the original treatment of diabetes. It is actually a hormone produced by your body that is now available in a very pure form. It has many advantages such as: it is effective no matter how high your blood sugar is, and it works consistently and predictably. The major disadvantages of insulin are that, for most people, it requires multiple injections each day, can cause dangerously low blood sugar if not properly managed, and tends to cause increased appetite and weight gain.

Sulfonylureas were the next class of antidiabetes drugs available in America. They work by increasing insulin secretion by the pancreas. Although many have been used at one time or another, the major ones prescribed now are: glyburide (DiaBeta®, Micronase®), glipizide (Glucotrol®) and glimepiride (Amaryl®). The major advantages of these drugs are that they are inexpensive and can be taken as pills once or twice a day. They are also effective within a short period of time. Disadvantages are the risk of dangerously low blood sugars, and the potential for weight gain.

Metformin (Glucophage®) is an agent that has been available in America since the mid-1990’s. It works by causing the liver to produce less sugar. It does not cause weight gain and, in fact, often causes weight loss. It is fairly expensive, causes a lot of gastrointestinal problems (nausea, diarrhea, etc.) and may cause a fatal blood acid problem in people with a weak heart, kidneys or liver.

Thiazolidinediones (also known as glitazones) include rosiglitazone (Avandia®) and pioglitazone (Actos®). Troglitazone (Rezulin®) was another member of this class that was removed from the market by the FDA because of liver injury. These drugs cause the muscle cells in the body to take more sugar out of the blood, leading to lower blood glucose levels. These agents are not ones that cause weight gain, but do not cause weight loss either. Many experts think that the benefits of these drugs and metformin are probably greater than just the benefits expected from the reduction of blood sugar. Disadvantages of this class are rare liver injury and very high cost. They also cause fluid retention and this can make heart failure worse.

Many other medicines are available for diabetes, and there is no way that we can talk about all of them here. It is absolutely necessary that you do not discontinue diabetes medicines without consulting a physician. I do hope, however, that this information will help you to understand diabetes medicines and give you some things to discuss with your physician or pharmacist.