Medicines for type 2 diabetes

Also called anti-diabetic medicines

When you have type 2 diabetes, your body does not make enough insulin or does not use it well enough, resulting in raised blood glucose levels. When used with a healthy diet and exercise, diabetes medicine can effectively lower your blood glucose levels.

The main aim of treatment for diabetes is to reduce your risk of getting complications by controlling your blood glucose levels. Having constantly raised blood glucose levels damages your blood vessels and nerves, leading to problems affecting your kidneys, feet and eyes. Your risk of stroke and heart attacks also increases. 

On this page you will find information on:

When are medicines used for type 2 diabetes?

Diabetes medications are used to lower blood glucose levels when lifestyle changes have not been successful. Sometimes, medicines may be prescribed at diagnosis, if blood glucose levels are very high. Diabetes medication does not replace lifestyle changes. They are used in addition to eating a healthy balanced diet, weight loss and exercising regularly. Watch a video: what you need to know about diabetes medications

Examples of diabetes medicines

There are a variety of medicines used to treat type 2 diabetes – most are available as tablets. The most commonly prescribed medicine is metformin. Some people also need insulin, which is available as an injection only.

Your diabetes may be well controlled on one medicine alone, or you may need a combination of medicines, including 
a combination of tablets and insulin injection. Every person’s care plan is different and your health care provider will work with you to find out the best treatment plan for you. 

Diabetes medication Description

Most people with type 2 diabetes are started on metformin tablets.

  • Metformin is especially useful if you are overweight or obese because it doesn't cause weight gain. 
  • It works by improving your body's response to the insulin you naturally make. It also decreases the amount of glucose made by your liver and increases the use of glucose by your muscles.
  • It is usually taken two times a day, with or after food. 
  • A side effect of metformin may be diarrhoea (runny poos), but this is improved when it is taken with food. Read more about metformin.
Other diabetes medicines These medicines are usually prescribed if you are unable to take metformin or if your blood glucose levels have not been lowered successfully with metformin alone. Combining medications can be a more effective way to lower your blood glucose levels. Click on the links below to find out more about each medication.
 Insulin Insulin injections are used when your blood glucose levels have not been lowered successfully with tablets. This is usually when your body no longer produces enough insulin. Insulin medication is very similar to natural human insulin. Insulin is given as an injection, under the skin. It cannot be given as tablets because chemicals in the stomach destroy it. There are various different types of insulin. Read more about insulin

Tips for taking diabetes medicines

  • Get to know your diabetes medicines: for your medicines to work well, you need to take them as prescribed. Make sure you understand the right time to take them and any special instructions about timing around meals. Ask your doctor, nurse or pharmacist if you are unsure. Read more about questions to ask about your diabetes medicines.
  • Develop a routine for taking your medication: ask your pharmacist if medications should be taken at a certain time of day or without food. Then create a daily habit. This might involve taking medicines with breakfast or right before bed. If you have problems fitting your medicines into your everyday life (work schedule, meals, activities) ask for help or suggestions to make your medication routine simpler to follow.
  • Pill boxes or blister packs: ask your pharmacist about aids to help you to give medication as prescribed, for example using pill boxes or blister packs. Read more about remembering to take your medicine.
  • Keep a record of all medications, including over-the-counter (OTC) medicines such as vitamins, herbal supplements and complementary medicines. Take this record to medical appointments, and ask your doctor or pharmacists before you take anything new so they can check that it is safe for you.
  • Have a sick day plan: if you are taking diabetes medicines and are unwell with the flu, or other infections such as gastro (vomiting or diarrhoea), urinary tract infections, skin infections or chest infections, you need to take extra care. In these situations, blood glucose levels can become more difficult to manage. Read more about diabetes sick day plan.
  • Side effects – talk to your doctor or pharmacist: diabetes medicines affect each person differently. These medicines can sometimes cause side effects. The side effects will depend on your body and the type of medicine you are taking. Tell your doctor, pharmacist or nurse about any problems you may be having with your medicines. They may recommend a change to your medicine or give you tips to help you deal with the side effects. Read more about medicines and side effects.
  • Be patient: it may take a while to find a medicine regimen that works for you. Your adjustment process will have its highs and its lows, but your health professionals are there to help guide you if you have problems.

Questions to ask about your diabetes medicines

Understanding what your medicines are for and how to take them will help ensure you get the most benefit from them. Here are some questions that you might ask your doctor, pharmacist or nurse:  

  • What is the name of my medicine and what does it do?
  • What is the strength (for example, how many milligrams)? 
  • When should I expect the medicine to start working, and how will I know if it is?
  • How much should I take for each dose?
  • At what times of day should I take my medicine?
  • Am I supposed to take it with something to eat?
  • What should I do if I forget to take a dose?
  • Are there any side effects to watch out for?
  • Can my diabetes medicine cause low blood glucose?
  • What should I do if my blood glucose is too low?
  • What should I do if I feel better and don't want to finish taking all of it?
  • Is it okay to take with other medicines, alcohol or natural remedies?
  • What should I do if it doesn't seem to work?

Learn more

Return to main diabetes page


  1. Treatment of diabetes New Zealand Formulary
  2. Managing patients with type 2 diabetes: from lifestyle to insulin BPAC, 2015
  3. Vildagliptin: a new treatment for type 2 diabetes BPAC, 2018
  4. Management of type 2 diabetes New Zealand Primary Care Handbook 2012
Credits: Sandra Ponen, pharmacist. Reviewed By: Angela Lambie, Pharmacist, Auckland Last reviewed: 11 Apr 2019