Many people feel unsure about their diabetes medicines. You might recognise some of these thoughts:

• “I take the tablets but I’m not really sure what they do.”
• “My medicines keep changing and I don’t know why.”
• “I’m worried about side effects but don’t want to annoy the doctor.”

This guide is not here to tell you which medicines you personally should be on. Instead, it offers a plain-language overview of the main groups of medicines for type 2 diabetes, what they are trying to do in the body, and the sort of questions you can safely ask at your next review.

It works best if you read it alongside our other diabetes pieces on test results, food and movement:

HbA1c, Finger-Prick Tests & Daily Life  ·  Diabetes-Friendly Plate on a Budget  ·  Movement After Meals

What Are Diabetes Medicines Trying to Achieve?

However complicated the names sound, most type 2 diabetes medicines are trying to do one or more of the following:

• Help your body use insulin better (improve insulin sensitivity).
• Help your body release more insulin when it is needed.
• Slow down how quickly sugar from food enters your bloodstream.
• Help you pass extra sugar out of the body in your urine.
• Support weight loss in some people.
• Protect your heart and kidneys if you are at higher risk.

When you understand what a medicine is “trying to do”, it becomes easier to notice whether it is helping you – and to have a calm conversation if something feels wrong.

Metformin – Often the First Tablet

For many people, the first tablet offered for type 2 diabetes is metformin. You might see brand names, but “metformin” is the drug name your team will use.

In simple terms, metformin:

• Helps your body use insulin more effectively.
• Reduces the amount of sugar released by your liver.
• Does not usually cause low blood sugar (hypos) when taken on its own.

Common issues people mention include:

• Stomach upset, wind or loose stools – especially at the start.
• Feeling full or mildly queasy.

If you struggle with metformin, do not simply stop it on your own. Your GP or nurse may be able to:

• Adjust the dose more slowly.
• Switch you to a modified-release version that is gentler on the stomach.
• Consider alternative tablets if it still does not suit you.

Sulfonylureas – Helping the Pancreas Release More Insulin

A group of medicines called sulfonylureas includes drugs such as gliclazide and glimepiride. These tablets:

• Encourage the pancreas to release more insulin.
• Can lower blood sugar quite strongly.

Because of this, they can sometimes cause low blood sugar (hypos), especially if:

• You miss or delay a meal.
• You lose a lot of weight, become more active or are unwell.
• You have kidney problems or other illnesses.

Your team should explain:

• What hypo symptoms feel like for you (for example shaking, sweating, confusion).
• How to treat a hypo quickly and safely.
• Whether you should check your blood sugar more often on these medicines.

DPP-4 Inhibitors – “Gliptins” That Help Hormones Work Better

Another group often used in type 2 diabetes is called DPP-4 inhibitors, sometimes known as “gliptins” (for example sitagliptin, linagliptin, alogliptin).

In plain language, these tablets:

• Help gut hormones that signal “food has arrived” last longer.
• Encourage your body to release more insulin when food is present.
• Reduce the amount of sugar your liver releases.

They usually:

• Do not cause weight gain.
• Have a lower risk of hypos than some other tablets, especially when not combined with sulfonylureas or insulin.

Your GP, nurse or pharmacist should explain any blood tests needed to monitor your kidneys or liver while you are on these medicines.

SGLT2 Inhibitors – Passing Extra Sugar Out Through the Urine

You may have heard of medicines such as empagliflozin, dapagliflozin or canagliflozin. These are SGLT2 inhibitors.

They work mainly by:

• Helping your kidneys pass extra sugar out of the body in your urine.
• Reducing blood sugar levels.
• Often supporting modest weight loss.

They can also have important heart and kidney protection benefits for some people at higher risk, which is why your team may recommend them even if your blood sugar looks fairly controlled.

Things to be aware of (your team should talk through these in detail):

• Higher risk of genital or urine infections – good hygiene and early treatment are important.
• Needing to pass urine more often.
• Rare but serious side effects such as ketoacidosis – you should be given clear sick-day rules and emergency advice.

GLP-1 Receptor Agonists – Injections or Tablets That Mimic Gut Hormones

Some people are offered medicines such as semaglutide, dulaglutide or liraglutide. These are GLP-1 receptor agonists. Many are injections given weekly; some now come as tablets.

In everyday language, GLP-1 medicines:

• Act like a natural gut hormone that tells the body “you’ve eaten enough”.
• Help you feel fuller sooner and for longer.
• Encourage insulin release when food is present.
• Slow how quickly the stomach empties food into the intestines.

This combination can:

• Lower blood sugar.
• Support weight loss in many people.
• Provide heart and kidney benefits for some groups at high risk.

Common early side effects include:

• Feeling sick or “off food”.
• Occasional vomiting or diarrhoea.

Your team should explain how to start slowly, what to watch out for, and when to seek urgent help (for example, severe stomach pain that does not settle).

Insulin – When and Why It May Be Added

Some people with type 2 diabetes eventually need insulin injections, either on their own or alongside tablets. This can feel like a big step and often causes worry.

Reasons insulin may be recommended include:

• Blood sugar remains high despite tablets and lifestyle changes.
• Serious illness or surgery that makes control more difficult.
• Kidney or liver problems that limit other medicine options.
• Very high blood sugars at diagnosis that need quicker control.

Insulin:

• Is a hormone your body already makes – injections are a way of “topping it up”.
• Can be given in different types (background, mealtime, or mixed).
• Always needs clear education about hypos, dose changes and monitoring.

Starting insulin is not a “failure”. It is one of several tools. The key question is always: “What gives me the best chance of feeling well and protecting my body in the long term?”

How Do Medicines Fit with Food, Movement and Tests?

Tablets and injections cannot work in isolation. They sit alongside:

• Your eating pattern and portion sizes.
• Your day-to-day movement and activity.
• Your sleep, stress levels and other health conditions.
• Your regular blood tests (for example HbA1c, kidney function, cholesterol).

You may find it helpful to think of your care as four linked strands:

• Tests: understood via our piece “HbA1c, Finger-Prick Tests and Daily Life – How They Connect.”
• Food: supported by “Building a Diabetes-Friendly Plate on a Budget.”
• Movement: supported by “Movement After Meals – A Powerful but Overlooked Tool.”
• Medicines: explored in this article.

You do not have to change everything at once. Your team can help you decide which strand to focus on next.

Ten Questions You Can Safely Ask About Your Medicines

You are allowed to understand your treatment. These questions are reasonable, respectful and useful for your GP, nurse or pharmacist:

1. “Which medicines am I taking specifically for my diabetes, and what is each one trying to do?”
2. “Which of my medicines could cause low blood sugar, and what should I look out for?”
3. “What tests do I need to have regularly while I am on these medicines (for example kidneys, liver, HbA1c)?”
4. “Are any of my tablets doing similar jobs – is there anything we could simplify?”
5. “How will we know if this new medicine is helping – what should improve or change?”
6. “What are the most common side effects, and which ones mean I should seek urgent help?”
7. “If I become unwell with vomiting, diarrhoea or infection, what should I do with my diabetes medicines?”
8. “Do any of these medicines help protect my heart or kidneys as well as my blood sugar?”
9. “If I am struggling to afford prescriptions or to manage my tablets, who can help me?”
10. “Could we write a simple medicines list in plain language that I can keep at home and share with family or carers?”