The information provided here is meant to give you a general idea about each of the medicines listed below. Only the most general side effects are included. Ask your doctor if you need to take any special precautions. Use each of these medicines only as recommended by your doctor, and according to the instructions provided. If you have further questions about usage or side effects, contact your doctor.

Some people are able to manage type 2 diabetes with diet and exercise. But in many cases, medicines may need to be added to this treatment plan to help you control your blood sugar.

Oral antidiabetes medicines, often referred to as “oral agents” or oral hypoglycemic agents by doctors, are used to treat type 2 diabetes. They lower blood sugar levels in a variety of ways. Since each class works differently, they may be used in combination. All of these drugs work best when they are part of a total treatment program that includes a healthful diet and regular exercise.

Despite diet, exercise, and oral medicines, some people with end-stage type 2 diabetes may need to take insulin, exenatide, or pramlintide to keep their blood sugar in good control.

Prescription Medications

Sulfonylurea Drugs

Meglitinides

Biguanide

Thiazolidinediones

Alpha-glucosidase inhibitors

D-phenylalanine derivatives

Dipeptidyl peptidase-4 (DPP-4) inhibitors

Insulin

Exenatide

Pramlintide

Sulfonylurea Drugs

Common names include:

Sulfonylurea drugs stimulate the beta cells in the pancreas to make more insulin. They also help your body's cells use insulin better.

Sulfonylureas are generally taken 1-2 times per day, 30 minutes before a meal. You should take them at the same time each day, just as you plan your meals at about the same time every day.

All sulfonylureas have similar effects on your blood sugar level, but they may have different side effect profiles. Based on the results of your blood sugar monitoring, your doctor will work with you to adjust your dosage. Talk to your doctor about which side effects you should watch out for.

Special Considerations

Sulfonylurea drugs help to control your blood sugar by stimulating the production and release of insulin. Therefore, there is the chance that they can cause hypoglycemia (low blood sugar). Be sure to talk with your doctor and a registered dietitian about balancing the amount of food you eat with the amount of medicine you take to help reduce the risk of hypoglycemia.

Some of these drugs may cause negative effects if taken with alcohol. Chlorpropamide is the most common drug to cause such effects, which include vomiting and flushing.

Sulfonylurea drugs can also increase the risk of heart attack and congestive heart failure. Talk to your doctor about your individual risk factors for heart disease.

Meglitinides

Like sulfonylureas, repaglinide helps the pancreas produce more insulin. However, it works faster than sulfonylureas, allowing for more flexible timing of doses and meals.

Also like sulfonylureas, repaglinide also carries the risk of hypoglycemia. So, you should talk with your doctor and/or a registered dietitian about balancing the amount of food you eat with the amount of medicine you take. This will help to reduce the risk of hypoglycemia.

Repaglinide is usually taken 2-3 times a day before each meal.

Biguanides

Metformin works in the liver to make it produce less glucose and make your body more sensitive to insulin. Metformin can also lower blood fat levels and possibly lead to minor weight loss, which can ultimately help with blood sugar control.

Metformin is usually taken 1-3 times a day with meals. Metformin does not cause the body to make more insulin. Therefore, when it is used alone, it rarely causes hypoglycemia (low blood sugar). However, when combined with other diabetes drugs, it can cause hypoglycemia.

Special Considerations

Tell your doctor if you drink more than 2-4 alcoholic drinks a week, since metformin is poorly tolerated with alcohol. Also, if you are having surgery, or a test that requires dye, make sure the doctor knows you are taking metformin. It will need to be stopped temporarily.

Thiazolidinediones

Common names include:

These medicines are also called "insulin sensitizers" because they make the cells in your body more sensitive to or better able to use insulin. Specifically, they work in the muscle and fat cells. They may also help decrease the amount of glucose released by the liver. These drugs do not cause the body to make more insulin. Therefore, when they are used alone, they rarely cause hypoglycemia (low blood sugar). However, when they are combined with other diabetes drugs, they can cause hypoglycemia.

This type of medicine is usually prescribed once per day. It may be taken with or without food, at about the same time each day.

Special Considerations

  • In rare cases, thiazolidinediones can harm your liver. Therefore, your doctor will regularly monitor your liver function with blood tests when you are taking one of these drugs.
  • People who take rosiglitazone may be at an increased risk for having a heart attack . Discuss your risk with your doctor.
  • This group of medicine may also increase the risk of fractures in women.

Alpha-glucosidase Inhibitors

Common names include:

These medicines are also called "starch blockers" because they slow down the digestion of carbohydrates (starches and sugars), which are the major food sources of glucose. This slow-down in digestion leads to a slow-down in absorption, and therefore, a slower increase in blood sugar after a meal. When used alone, alpha-glucosidase inhibitors do not cause hypoglycemia, however when combined with other diabetes drugs, they may cause this side effect.

Alpha-glucosidase inhibitors should be taken with the first bite of each main meal. When you initially start this medicine, your doctor may have you take it less frequently. You will build up the dose over time as your body adjusts to the medicine.

Special Considerations

Table sugar (sucrose) is not effective at treating hypoglycemia when you are taking these drugs because alpha-glucosidase inhibitors slow the digestion of sucrose. If symptoms of hypoglycemia occur while you are taking one of these medicines, the following foods can be used to treat it:

  • 3-4 glucose tablets
  • 10 ounces of milk

D-phenylalanine Derivatives

Nateglinide helps the pancreas quickly produce more insulin. It can be prescribed for use with each meal and should be taken within 30 minutes before meals. Do not take a dose of Nateglinide if you skip a meal. Although this drug works when taken alone, for some people it may be more effective when it is combined with metformin (Glucophage). Nateglinide also carries the risk of hypoglycemia (low blood sugar).

Dipeptidyl Peptidase-4 (DPP-4) Inhibitors

Common names include:

  • Sitagliptin (Januvia)
    • The FDA has warned that sitagliptin may increase the risk of acute pancreatitis.
  • Vildagliptin (Galvus)
  • Saxagliptin (Onglyza)

DPP-4 inhibitors lengthen the activity of certain proteins, which increase the release of insulin after your blood sugar level rises with a meal. The medicine does this by blocking a specific enzyme (DPP-4), which is responsible for breaking down these proteins.These drugs can enhance your body’s own ability to reduce the elevated blood sugar levels.

This class of medicine is meant to be used together with diet and exercise to help improve the blood sugar levels. It can be used alone or added to other commonly prescribed oral antidiabetic drugs.

When to Contact Your Doctor

Diabetes pills do not work for everyone. Also, they may become less effective after a few months or years. Until you are well accustomed to your medicines, be sure to monitor your blood sugar levels regularly and record the information to tell your doctor. This will help you and your doctor recognize if your pills are not working properly and if you need a change in dosage or even treatment.

Report the following to your doctor immediately:

  • Fasting blood glucose (before breakfast) less than 100 milligrams per deciliter (mg/dl) [5.6 mmol/L]
  • Symptoms of hypoglycemia: sweatiness, shakiness, and confusion

When you start taking diabetes medicines, they may cause some side effects. (Each drug can cause different effects, so ask your doctor what to expect from your drug regimen.) However, many of these effects go away as your body adjusts to the medicine. If side effects persist, tell your doctor.

Once your diabetes is under adequate control on oral medicines, it may not be necessary to continue monitoring your blood sugar levels on a regular basis. Many type 2 diabetes (not taking insulin) can be adequately managed by using another test called glycosylated hemoglobin or hemoglobin A1c (HbA1c), which is done in a doctor’s office. Unlike blood sugar levels, HbA1c has the advantage of measuring average blood glucose levels over the last three-month period, which marks the effectiveness of diabetes management over the long-term. Most people with diabetes are recommended to keep their HbA1c levels below 7% to avoid or delay diabetic complications.

In a recent study of 453 moderately well-controlled type 2 diabetics who did not take insulin, researchers investigated whether patients who undertook regular self-monitoring of their blood sugar had better control over their diabetes than patients who did not monitor their blood sugar for an average of three years. They found no significant difference in HbA1c levels between the groups, suggesting that regular blood sugar testing in diabetics whose condition is under reasonably good control without insulin may not be necessary. However, you should be sure to have a discussion with your physician before discontinuing blood sugar monitoring.

Insulin

In almost all type 2 diabetes, the pancreas eventually stops making adequate amounts of insulin. To help control your diabetes, you may need to inject insulin. Insulin must be taken as an injection. If it were taken by mouth, it would be digested by the stomach before it reached your bloodstream where it needs to do its work.

Insulin Injection Sites

© 2009 Nucleus Medical Media, Inc.

To work properly, the amount of insulin you use must be balanced with the amount and type of food you eat, the amount of exercise you do, and the other diabetes medicines you are taking.

The amount of insulin you take must be balanced with the amount and type of food you eat and the amount of exercise you do. If you change your diet, your exercise, or both without changing your insulin dose, your blood glucose level can drop too low or rise too high. Before getting insulin, you should check your blood glucose level with a blood glucose meter. This will help you to determine how much insulin you need. Current insulin treatment regimens usually employ some combination of rapid-acting and long or very long-acting insulin. Insulin is usually given before meals and at bedtime.

All About Insulin

The three characteristics of insulin are:

  • Onset—the length of time it takes for the insulin to reach the bloodstream and begin lowering blood glucose after it is injected
  • Peak Time—the time during which insulin is at its maximum strength in terms of lowering blood glucose levels
  • Duration—how long the insulin continues to lower blood glucose

The main types of insulin available are:

Type of insulinOnset*Peak time*Duration*Notes on use
Rapid-acting10-30 minutes0.5-3 hours3-5 hoursInject immediately before a meal
Regular- or Short-acting0.5-1 hour2-5 hours5-8 hours 
Intermediate-acting
(NPH )
1-2.5 hours3-12 hours18-24 hoursOften used in combination with short-acting insulin
Long-acting
Levemir (detemir)
0.5-3 hours10-20 hours20-36 hours; nearly a continuous insulin releaseCan combine a long-acting with a short-acting to provide proper peaking of insulin at mealtimes
Very long-acting
Insulin glargine (Lantus)–enters the body quickly, and has long-lasting effects
1 hourn/a20-24 hours, continuous insulin releaseMay not be mixed with other types of insulin
Pre-Mixed—mixture of short-acting and intermediate-acting insulinsOnset*Peak time*Duration*
Humulin 50/5030 min2-5 hours18-24 hours
Humalog mix (75/25)15 min0.5-2.5 hours16-20 hours
Humulin 70/3030 min2-4 hours14-24 hours
Novolin 70/3030 min2-12 hoursup to 24 hours
Novolog 70/3010-20 min1-4 hoursup to 24 hours

*Each person has a unique response to insulin, so the times mentioned here are approximates.

In the table below are types of insulin and common brand names.

Type of insulinBrand names
Rapid-acting Humalog (insulin lispro)
NovoLog Cartridge (insulin aspart)
Regular- or Short-acting Humulin R (regular)
Iletin II Regular
Novolin R
ReliOn/Novolin R
Intermediate-acting Humulin N (NPH)
Iletin II NPH
Novolin N (NPH)
ReliOn/Novolin N (NPH)
Long-acting Levemir (detemir)
Lantus (insulin glargine)

Methods of Insulin Delivery

In the past, for insulin to be used by the body, it must be moved through the outermost layer of skin and into fatty tissue.

There are a few ways of getting insulin into your body by injection. Some examples are:

Syringe —The syringes you will use are small and have fine points and special coatings that help to make injecting as easy and painless as possible. When insulin injections are done properly, most people find that they are relatively painless.

Insulin is usually given as a subcutaneous injection . This means that the needle goes into the fat layer between the skin and the muscle to deliver a certain amount of medicine.

Pump —This is a computerized device, about the size of a beeper that you wear on your belt or in your pocket. It delivers a steady, measured dose of insulin through a flexible plastic tube called a cannula.

With the aid of a small needle, the cannula is inserted through the skin into the fatty tissue and is taped in place. In some products, the needle is removed and only a soft catheter remains in place. You control the release of insulin from the pump, based on your meals and your blood sugar level.

Because the pump continuously releases tiny doses of insulin, this delivery system most closely mimics the body's normal release of insulin. Also, pumps can deliver very precise insulin doses for different times of day, which may be necessary to correct the dawn phenomenon—the rise of blood sugar that occurs in the hours before and after waking.

Pen —The insulin pen looks very much like an old-fashioned cartridge pen, except that it has a needle and holds a cartridge of insulin. Pens are particularly useful for people who are often on the go, or whose coordination is impaired.

Note:

  • Check your insulin's expiration date. If you haven't finished it before then, throw the rest away.
  • Store unopened bottles of insulin in the refrigerator. Do not store your insulin at extreme temperatures.
  • Keep the bottle of insulin you are using at room temperature. Injecting cold insulin can sometimes make the injection more painful. (Most pharmacists believe that insulin kept at room temperature will last for about one month.)

Exenatide

After eating a meal, a hormone, Glucagon-like peptide-1 (GLP-1) is produced in the stomach and intestines. This hormone leads to insulin release from the beta cells in the pancreas. Moreover, it helps to control blood glucose levels by reducing the appetite and increasing the sense of fullness. Exenatide belongs to a family of chemicals which mimics the effects of GLP-1.

This medicine is meant to be used in type 2 diabetes patients whose blood glucose is not controlled with oral antidiabetes medicines. Exenatide may cause nausea and appetite suppression, which can lead to weight loss. This injectable medicine and is available in a disposable pen.

Pramlintide

Amylin is a hormone produced by the same beta cells which produce insulin. Amylin is released at the same time as insulin. Moreover, amylin reduces glucagons release and enhances the sense of fullness after eating a meal. Together with insulin, amylin helps lower the blood sugar level. Pramlintide is chemically related to amylin.

Pramlintide is used together with insulin in people who fail to achieve the desired blood glucose levels despite getting the optimal doses of insulin. This drug is given by injection immediately before a meal. The elderly should use this drug with special care.

Special Considerations

If you are taking medicines, follow these general guidelines:

  • If you give yourself insulin injections, always use a new needle. This will reduce your risk of infection.
  • Take your medicine as directed. Do not change the amount or the schedule.
  • Do not stop taking them without talking to your doctor.
  • Do not share them.
  • Know what the results and side effects. Report them to your doctor.
  • Some drugs can be dangerous when mixed. Talk to a doctor or pharmacist if you are taking more than one drug. This includes over-the-counter medicine and herb or dietary supplements.
  • Plan ahead for refills so you do not run out.