by Schroeder K

Healthy lifestyle choices including diet, exercise and weight control are main part of type 2 diabetes management. Medication may be needed to achieve target blood sugar (glucose) levels. Sometimes a single medication is effective. In other cases, a combination of medications works better.

The list of medications for type 2 diabetes is long and may be confusing. Learning about these drugs, how they're taken, what they do and what side effects they may cause will help you discuss treatment options with your care team.

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

Anti-diabetes medications that are taken by mouth, often referred to as oral agents, are used to treat type 2 diabetes. They lower blood glucose levels in a variety of ways. Since each class works differently, these medications may be used in combination. All of these drugs work best when they are part of a total treatment program that includes healthy eating and regular exercise.

Despite diet, exercise, and oral medications, some people with long-standing type 2 diabetes may need to take insulin or other medications to control their glucose levels.

Several classes of type 2 diabetes medicines exist. Each class of medicine works in different ways to lower blood sugar. A drug may work by:

  • Stimulating the pancreas to produce and release more insulin
  • Inhibiting the production and release of glucose from the liver
  • Blocking the action of stomach enzymes that break down carbohydrates
  • Improving the sensitivity of cells to insulin
  • Inhibiting the reabsorption of glucose in the kidneys
  • Slowing how quickly food moves through the stomach

Each class of medicine has one or more drugs. Some of these drugs are taken as a pill, while others must be injected.

Prescription Medications



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 glucose control.

Metformin is usually taken 1-2 times a day with meals. Metformin does not cause the body to make more insulin. When it is used alone, it rarely causes hypoglycemia (low blood glucose levels). 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 contrast dye for scans, make sure the doctor knows you are taking metformin. The medication will need to be stopped temporarily.

Sulfonylurea Drugs

Common names include:

  • Chlorpropamide
  • Glipizide
  • Glyburide
  • Glimepiride
  • Tolazamide
  • Tolbutamide

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

These medications are generally taken 1-2 times per day, 30 minutes before a meal. This medication should always be taken with food. This is to reduce the risk of developing hypoglycemia.

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

Special Considerations

Sulfonylurea drugs help to control your blood glucose by stimulating the production and the release of insulin. Therefore, there is the chance that they can cause hypoglycemia. Be sure to talk with your doctor and a registered dietitian about balancing the amount of food you eat with the amount of medication 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 these effects, which includes vomiting and flushing.

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


Common names include:

  • Repaglinide
  • Nateglinide

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

Also like sulfonylureas, these medications can increase 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 medication you take. This will help to reduce the risk of hypoglycemia.

Repaglinide is usually taken 2-4 times a day, within 15-30 minutes before each meal.


Common names include:

  • Rosiglitazone
  • Pioglitazone

These medications 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. Pioglitazone has an added benefit of improving cholesterol levels.

When combined with other diabetes drugs, thiazolidinediones may cause hypoglycemia.

This type of medication 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.
  • This group of medications can increase your risk of edema and heart failure.
  • This group of medications may also increase the risk of fractures in women.
  • Pioglitazone may increase your risk of bladder cancer.
Alpha-glucosidase Inhibitors

Common names include:

  • Acarbose
  • Miglitol

These medications 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 glucose 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 medication, your doctor may have you take it less frequently. You will build up the dose over time as your body adjusts to the medication.

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 medications, glucose tablets should be used to treat it.

Dipeptidyl Peptidase-4 (DPP-4) Inhibitors

Common names include:

  • Sitagliptin
  • Vildagliptin
  • Saxagliptin
  • Linagliptin

DPP-4 inhibitors lengthen the activity of certain proteins, which increase the release of insulin after your blood glucose level rises with a meal. The medication 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 glucose levels.

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

Glucagon-like Peptide-1 Receptor Agonist
  • Exenatide
  • Liraglutide

After eating a meal, a hormone called glucagon-like peptide-1 (GLP-1) is produced in the stomach and intestines. This hormone leads to insulin being released from the beta cells in the pancreas.

GLP-1 agonists are meant to be used in people with type 2 diabetes whose blood glucose is not controlled with oral anti-diabetes medications.

Side effects from these medications may include:

  • Low blood glucose
  • Headache
  • Nausea, vomiting
  • Diarrhea
  • Irritation where the shot is given

There is also a concern that some of these agents may increase the risk of developing a rare type of thyroid tumor (medullary cancer) in certain people. Discuss this with your doctor.



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 glucagon's release and enhances the sense of fullness after eating a meal. Together with insulin, amylin helps lower the blood glucose level. Pramlintide is chemically related to amylin. And like amylin, Pramlintide reduces appetite, and its use has been associated with weight loss.

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.

Sodium-Glucose Co-Transporter 2 (SGLT-2) Inhibitors

SGLT-2 inhibitors are oral medications that block the reabsorption of glucose in the kidneys. This means more glucose is passed in the urine.

Side effects from this medication may include:

  • High blood pressure
  • Kidney problems
  • Hypoglycemia
  • Increased risk of genital fungal infections
  • Increased low-density lipoprotein (LDL) cholesterol
Bile Acid Binders


Colesevelam is an oral medication. The medication binds to food in the intestines and blocks it from being absorbed into the body. It is used with other antidiabetes drugs, and with diet and exercise. It is not recommended in people with a history of bowel obstruction, high triglycerides, or pancreatitis caused by high triglycerides.

Side effects from this medication may include:

  • Constipation
  • Cold symptoms, including stuffy nose or sore throat
  • Indigestion
  • Hypoglycemia
  • Nausea
  • High blood pressure
Dopamine Agonist


Dopamine agonists reduce the amount of prolactin in the bloodstream by blocking the release of prolactin from the pituitary gland. It has also been shown to reduce blood glucose leves in people with diabetes.

It is used in the treatment of pituitary and endocrine disorders. It is not recommended in people who have uncontrolled high blood pressure, women who are breastfeeding, or those who experience fainting with migraine headaches. Talk to your doctor if you have liver or kidney problems.

Side effects from this medication may include:

  • Nausea, vomiting
  • Low blood pressure, which can lead to lightheadedness and fainting
  • Headaches
  • Raynaud's phenomenon
  • Daytime sleepiness


In almost all patients with type 2 diabetes, the pancreas eventually no longer makes enough insulin for the body. 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
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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 medications you are taking.

If you change your eating habits, your exercise, or both without changing your insulin dose, your blood glucose level can drop too low or rise too high. Current insulin treatment regimens usually employ some combination of rapid-acting and long- or very long-acting insulin.

All About Insulin

The 3 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 insulin Description
Rapid-acting This type of insulin works in about 5 minutes. It reaches its peak in about 1 hour and lasts for 2-4 hours.
Regular- or Short-acting This type of insulin works in about 30 minutes. It reaches its peak in about 2-3 hours and lasts about 3-6 hours.
Intermediate-acting This type of insulin works in about 2-4 hours. It reaches its peak in about 4-12 hours and lasts about 12-18 hours.
Long-acting This type of insulin works in about 6-10 hours and lasts for about 20-24 hours.

Insulin can also come in premixed forms, which combine intermediate-acting insulin with rapid- or short-acting insulin.

Methods of Insulin Delivery

There are several different ways of getting insulin into your body by injection. Some examples are:

  • Syringe—The syringes you will use are small and have fine needles with 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.
  • 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 who have poor coordination. The majority of pens are disposable.
  • Pump—This is a small computerized device 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. Because the pump continuously releases tiny doses of insulin, this delivery system most closely mimics the body's normal release of insulin.
  • 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.)

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 medications, be sure to monitor your blood glucose 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 any low blood sugars or symptoms of hypoglycemia to your doctor immediately.

When you start taking diabetes medications, 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 medication. If side effects persist, tell your doctor.

Once your diabetes is under adequate control on oral medications, it may not be necessary to continue monitoring your blood sugar levels on a regular basis. Type 2 diabetes (when 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 3-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. But individual goals may vary.

Special Considerations

If you are taking medications, follow these general guidelines:

  • Take the medication as directed. Do not change the amount or the schedule.
  • Ask what side effects could occur. Report them to your doctor.
  • Talk to your doctor before you stop taking any prescription medication.
  • Plan ahead for refills if you need them.
  • Do not share your prescription medication with anyone.
  • Medications can be dangerous when mixed. Talk to your doctor if you are taking more than one medication, including over-the-counter products and supplements.


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