Oral Medicines for Type 2 Diabetes

Diabetes pills can help to manage your blood sugar. These pills are not insulin. They work to manage your blood sugar in a few ways. You may be given a combination of medicines. Always follow your healthcare provider's instructions.

Some pills may put you at greater risk for low blood sugar (hypoglycemia). Watch for symptoms of low blood sugar (see below). Call your provider if low blood sugar happens often.

Type of diabetes pills


These pills help control the amount of sugar in your blood. They decrease the amount of sugar your liver makes. And they help your muscles use insulin better. You often take these medicines with or after each meal. Possible side effects and other problems include:

  • Diarrhea

  • Nausea

  • Vomiting

  • Belly (abdominal) bloating

  • A lot of gas

  • Metallic taste in mouth

  • Lower blood vitamin B12 levels from decreased absorption from the gastrointestinal tract of this vitamin

Have your vitamin B-12 levels checked often if you use these pills for a long time. This is even more important if you have anemia or peripheral neuropathy.


These pills help your body make more insulin. They are taken 30 minutes before a meal. Possible side effects include low blood sugar.

Alpha-glucosidase inhibitors

These pills slow the digestion of sugars and starches. They can help keep your blood sugar from going too high after a meal. Take them with the first bite of each main meal. Possible side effects include:

  • Stomach pain

  • Diarrhea

  • A lot of gas


These pills help your muscle cells use insulin better. Your healthcare provider may order lab tests to check your liver before prescribing these pills. He or she will also check it often while you are taking them. Possible side effects include: 

  • Weight gain

  • Extra fluid in your body and swelling

  • Higher risk for heart failure

  • Osteoporosis and higher risk for broken bones


These pills increase your insulin for a short time. You take them before meals. Possible side effects include:

  • Low blood sugar

  • Diarrhea

  • Headache 

  • Slightly raised risk for heart problems

DPP-4 inhibitors

These pills help lower blood sugar levels in people with type 2 diabetes. They are less likely to cause low blood sugar, unless you take them with a sulfonylurea. You take them once a day. Possible side effects include:

  • Upper respiratory tract infection

  • Stuffy or runny nose

  • Sore throat

  • Headache

Other side effects are under study.

SGLT-2 inhibitors

These pills help lower blood sugar levels in people with type 2 diabetes. They raise the amount of sugar that leaks into the urine. Possible side effects include:

  • Urinary tract infections

  • Genital fungal infections, especially in women

  • Dehydration

  • Low blood pressure

  • Increased bone fractures

  • Keotacidosis while blood sugar is only mildly raised above the target range

The FDA has issued a safety warning for the SGLT-2 inhibitor canagliflozin. Recent studies have shown that this medicine increases the risk of leg and foot amputations. If you are taking this medicine, tell your healthcare provider right away if you have any new pain or tenderness, sores, or infections in your legs or feet. Talk with your provider before stopping any diabetes medicine. 

Dopamine D2 receptor agonist (bromocriptine mesylate)

These pills help lower blood sugar levels in people with type 2 diabetes. Possible side effects of this medicine include:

  • Nausea

  • Vomiting

  • Feeling tired and weak (fatigue)

  • Dizziness

  • Headaches

Combination pills

These medicines may help keep your blood sugar in your target range. They also help your pancreas make more insulin. And they may help your muscles use insulin better. Side effects depend on which type of combination you use. Your healthcare provider can tell you more.

Watch for symptoms of low blood sugar

Symptoms include:

  • Headaches

  • Shakiness or dizziness

  • Hunger

  • Cold, clammy skin

  • Sweating

  • A hard, fast heartbeat

  • Confusion or irritability

If you think your blood sugar is low, check a blood sample with a meter. If the level is low, eat one of the "quick fix" foods below. They can help raise your blood sugar:

  • 3 to 4 glucose tablets

  • 1 serving of glucose gel

  • 1/2 cup (4 ounces) of any fruit juice

  • 1/2 cup (4 ounces) of regular (not diet) soda

  • 1 tbsp of honey or sugar

  • 5 to 6 pieces of hard candy

Recheck your blood sugar in 15 minutes. If it is still low, eat another serving. If it stays low after the second snack, seek medical care.


Online Medical Reviewer: Marianne Fraser MSN RN
Online Medical Reviewer: Raymond Kent Turley BSN MSN RN
Online Medical Reviewer: Robert Hurd MD
Date Last Reviewed: 11/1/2019
© 2000-2021 The StayWell Company, LLC. All rights reserved. This information is not intended as a substitute for professional medical care. Always follow your healthcare professional's instructions.