Author:

Catherine Tuck, MD

Medical reviewer:

Medically Reviewed On: November 05, 2003

Published on: November 05, 2003

Type 2 diabetes is the type of diabetes characterized by insulin resistance, in which the body is still able to make some insulin, but not enough for the body to handle sugar properly. It is usually treated with diet control, weight reduction, oral agents, or insulin. Having type 2 diabetes is often overwhelming for my patients. There are so many dos and don’ts, so many things you have to keep track of—like checking your eyes, checking your blood pressure, checking your cholesterol, checking your feet. There is also a lot to learn—how to count carbohydrates, how to predict what will make your blood sugar go up and down. The best advice I can give you is to find a doctor who you like and trust, someone who can take the time to go over all of his or her recommendations in detail. If you are lucky enough to have a diabetes team available, that’s even better. I work with both a nurse educator and a nutritionist as a team, to help our patients take control of their diabetes.

One positive thing about having diabetes in the year 2000 is that we have a lot of drugs we can use to help you get your blood sugars back to normal. This is extremely good news for you, because if you keep your blood sugar levels close to normal, you can prevent all of the terrible complications of diabetes. You should demand that your doctor help you get your blood sugar levels to normal—don’t let him or her tell you you’re doing fine when your blood sugars are still high.

Keep in mind that drugs are not magic. If you are taking a drug for diabetes control, it is still essential that you follow a good diet and get daily exercise. These two elements of diabetes control are the pillar on which all other diabetes treatment rests.
 

Keeping the Blood Sugars Close to Normal

I tell my patients that their blood sugar in the morning should be between 80 to 120 mg/dL before they eat, 80 percent of the time. In other words, since there will always be some daily variation in everyone’s blood sugar, 80 percent of the times that you’re checking your sugar, let’s say, during a week, your sugar should be in the 80 to 120 range. A normal blood sugar is actually between 60 to 105 mg/dL in the morning before you eat. So aiming for 80 to 120 is close to the normal range. Many of my patients are shocked when I tell them this. They are used to having blood sugars of 150 to 200 mg/dL or even higher when they wake up in the morning. That is too high.

After meals, your blood sugar should not go higher than about 150 mg/dL. You should check it about two hours after meals.

The best way to know if you are keeping your blood sugars under control is to do a test called the hemoglobinA1c, also known as the glycosylated hemoglobin. This test tells you what your blood sugar has been like, on average, during the past two to three months. If it is more than one percent higher than the normal range, you need to do a little better. Our test, for example, has a normal range from four to six percent. When a patient of mine has a test that is higher than seven percent, I try to get the patient either to work harder on diet and exercise or I increase their medications. The best thing, actually, would be to try to get your blood sugar all the way down to six percent and many patients are able to do that without too much trouble.

Your doctor should measure your hemoglobin A1c at least once every six months (better every three months) and tell you what it is so that you know how you are doing. I am shocked at how many of my patients have no idea what their hemoglobin A1c is!
 

Oral Medications for Type 2 Diabetes

The following medications are listed in the order that I usually recommend them.

Glucophage (metformin)
Glucophage is usually the first drug I recommend for type 2 patients who need medicines to get their blood sugars back to normal. This medicine has been used in Europe for decades and has been available in the United States for about five years. It works by helping the insulin that your body is still making work better. It also has a side effect which is very beneficial for most people with type 2 diabetes—it makes you lose a little bit of weight by decreasing appetite. Another good side effect for some people is that it tends to lower triglycerides (certain fats in the blood), which is great if you tend to have high triglycerides. The big plus if you take it by itself without any other diabetes medicines is that it never causes low blood sugar by working too much.

Glucophage is available in three dosage forms: 500, 850 and 1,000 milligrams. When I start my patients on Glucophage, I usually give them 500 milligrams once a day with food. After a week, if they are not having any gastrointestinal problems, I tell them to go up to two pills a day. Most people need the full dose to have an effect. The highest dose that seems to be effective is 1,000 milligrams twice a day. Alternately, you could take 850 milligrams three times a day, but since it is hard to take a pill three times a day, I usually try to have people take the 1,000 milligrams dose twice a day.

Glucophage does have some side effects. The most common side effect that some people have is gastrointestinal upset and diarrhea. It occurs in about 10 percent of patients and some of my patients just cannot tolerate the drug. There is no way to predict who will have problems with it, so I usually start people on the medicine slowly and tell them that if they have severe diarrhea to call me. If you start slowly and work up the dose there are usually no problems. Also, if you take the pills with meals, it is supposed to be a little bit easier on your stomach.

The most dangerous possible side effect of Glucophage is a very rare condition called lactic acidosis—this is a potentially life-threatening condition that requires immediate hospitalization and treatment. If you have kidney or liver problems, heart failure, or other severe medical illnesses, you should not take Glucophage, because there is a higher chance you might get lactic acidosis. Also, if you are on Glucophage and you are going to get any kind of intravenous dye for an x-ray or other procedure, your doctors will ask you to stop the Glucophage a few days ahead of time. This is because of the risk of your kidneys not working as well after the dye with the possibility of developing lactic acidosis after the procedure.

If you don’t have any of the medical problems listed above, then Glucophage is a very safe and effective medicine.

Sulfonylureas/meglitinides
Until a few years ago, these were the only oral drugs available for treating type 2 diabetes. Here is a list of all of the different sulfonylureas and meglitinides now available:
 
 

Generic name	Brand name
Acetohexamide	Dymelor
Chlorpropamide	Diabinese
Glimepiride	Amaryl
Glipizide	Glucotrol, Glucotrol XL
Glyburide	DiaBeta, Glynase PresTab, Micronase
Tolazamide	Tolinase
Tolbutamide	Orinase
Repaglinide	Prandin

Each of these drugs works by making your body produce more insulin. As you probably know, when you have type 2 diabetes, your body is able to make some insulin, but not quite enough to overcome the insulin resistance that your body has. When you take these drugs, your body is able to make a little more insulin and your blood sugar will come down back to normal.

These drugs are usually easy to take and they don’t upset your stomach. They work pretty well, especially if you’ve only had diabetes for a few years. Since these are the oldest drugs for diabetes, there are generic forms for most of them. If you pay for your own pills, these drugs are much cheaper than some of the newer drugs for diabetes.

The downsides of taking these drugs are as follows:

• If you take these drugs and then skip meals, you might develop a potentially dangerously low blood sugar; the drug makes your body produce insulin so you have to counter this with food. It can be problematic if you have an erratic eating schedule.
• It can sometimes lead to weight gain. Weight gain is often associated with a higher degree of insulin resistance and poorer sugar control. Generally, any time you improve controlling your blood sugar, you are likely to gain weight, because the extra sugar you were losing in your urine is now staying inside your body. (Glucophage is the only medicine that doesn’t usually cause gain weight, which is why I usually start with it.)

If you need to take a sulfonylurea, then I would recommend taking one of the brands that allows you to take a pill only once a day—Glucotrol XL or Amaryl.

Prandin is a new drug that some people find very convenient and helpful. It works slightly differently in that it only stays in your body for a short time. You take it right before you eat and it helps control your blood sugar for that meal, but then it goes away. This is great because it means you can skip meals—if you don’t feel like eating then you just don’t take Prandin and you don’t have to worry about a low blood sugar. On the other hand, you have to take it with every meal and it can be hard to have to take multiple pills each day.

Thiazolidinediones
These are the newest drugs available for people with type 2 diabetes. Rezulin was the first of these drugs to hit the market, but it caused serious liver damage and was taken off the market after the FDA decided there were other similar drugs that were safer. These newer and safer drugs are also thiazolidinediones. Their trade names are Avandia and Actos. These drugs work by helping the insulin that your body is already making work better, but they work on different parts of your body than metformin does.

The good thing about Avandia and Actos is that you can use them together with other types of diabetes medications like Glucophage and the sulfonylureas; all of their effects will add up, since they work differently. This means that if you are already taking the other two drugs, you can try taking this third kind of drug as well, and you may not have to take insulin shots right away. If you are taking insulin already but it is not working very well, which often happens when you have had type 2 diabetes for a long time, then adding one of these drugs to the insulin will often help bring your blood sugars back under control.

Another plus is that if you take one of these drugs by itself, you won’t get a low blood sugar, even if you skip meals. Also, they don’t upset your stomach or cause diarrhea like metformin can. Thiazolidinediones are unusual in that they take a long time to start working—sometimes up to six weeks—so if you’ve just started one of these pills, don’t expect to see results right away.

The downsides to the thiazolidinediones are as follows:

• They aren’t usually as effective or powerful as Glucophage or sulfonylureas so we don’t recommend them as the first drug to use.

• Like the sulfonylureas and insulin, they can cause weight gain.

• They can cause you to retain fluid, so if you have heart failure or any other problem that might result in swollen feet (i.e., conditions in which the body already may have difficulty in getting rid of excess fluid), you should be careful if you take these drugs.

• Because the newer drugs Avandia and Actos are related to the drug Rezulin, which was taken off the market, and because Avandia and Actos have only been on the market for a short time, the FDA has recommended that we check liver blood tests every two months on every patient who is taking them. This can be annoying to keep track of. However, even though we are very careful to check liver tests, the results from all studies so far show that Avandia and Actos are no more dangerous to the liver than the placebo pills, so I believe they are safe to take. However, these two drugs are fairly new and close attention should be paid to liver enzymes for patients taking Avandia or Actos.

Precose
Precose works by interfering with the absorption of carbohydrates in your stomach and intestines. The good thing about Precose is that it can work with other drugs to help lower your blood sugar and it doesn’t cause low blood sugar. However, it has pretty severe gastrointestinal side effects—flatulence, bloating, and diarrhea—and in my experience, most patients have a tough time handling it. Also, it isn’t the most powerful drug available and it’s still expensive. I don’t recommend it very often.
 

Summary

In addition to learning about type 2 medications, there are some other factors you need to consider. They are:

• If you are a woman who is of childbearing age, you should be aware that it isn’t safe to get pregnant while taking oral medicines. You should be treated with insulin and get normal blood-sugar readings before you get pregnant to reduce the chances of having birth defects related to diabetes.

• Each of these drugs works in different ways, so that we often combine them. I have many patients taking Glucophage, a sulfonylurea, and a thiazolidinedione. The medications are often used with insulin, to reduce the amount of insulin a patient has to take.

• A problem with all of the drugs for type 2 diabetes is that they usually work very well for a few years and then stop working. Usually when that happens, we add a second drug, and then a third, to the patient’s regimen. Most people need to take insulin eventually. If this happens to you, it doesn’t mean you’ve failed—it’s just what happens with type 2 diabetes.