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  1. About pioglitazone
  2. Key facts
  3. Who can and can't take pioglitazone
  4. How and when to take it
  5. Side effects
  6. How to cope with side effects
  7. Pregnancy and breastfeeding
  8. Cautions with other medicines
  9. Common questions

1. About pioglitazone

Pioglitazone is a medicine used to treat type 2 diabetes.

Type 2 diabetes is an illness where the body doesn't make enough insulin, or the insulin that it makes doesn't work properly. This can cause high blood sugar levels (hyperglycaemia).

Pioglitazone helps to control your blood sugar levels by helping your body make better use of the insulin it produces.

Pioglitazone is only available on prescription. It comes as tablets.

It also comes as tablets containing a mixture of pioglitazone and metformin. Metformin is another medicine used to treat diabetes.

2. Key facts

  • It's usual to take pioglitazone once a day.
  • You can take it with or without food.
  • After 3 to 6 months, your doctor will check your blood sugar levels to see if pioglitazone is working for you.
  • Some people find they put on weight when taking pioglitazone.
  • Pioglitazone is also called by the brand names Actos and Glidipion. The brand name for pioglitazone with metformin is Competact.

3. Who can and can't take pioglitazone

Pioglitazone can be taken by adults (aged 18 years and older).

Pioglitazone isn't suitable for some people. To make sure it's safe for you, tell your doctor if you:

  • have had an allergic reaction to pioglitazone or any other medicines in the past
  • have liver or heart problems
  • have or have ever had bladder cancer or blood in your pee
  • have illnesses caused by your diabetes, including macular oedema (a swelling at the back of your eye)
  • have a condition such as osteoporosis or osteopenia that affects your bones

If you're over 75 years old, you may be more likely to break a bone or get heart failure. Talk to your doctor about whether pioglitazone is suitable for you.

4. How and when to take it

Doses of pioglitazone can vary. Follow your doctor's instructions when taking this medicine.

You'll usually take pioglitazone once a day. You can take it at any time, for example in the morning or in the evening. Try to take it at the same time every day.

Swallow the tablet whole, with a glass or water. Do not chew it.

You can take pioglitazone with or without food.

How much will I take?

Pioglitazone comes as 15mg, 30mg and 45mg tablets.

The usual starting dose is 1 tablet (either 15mg or 30mg), taken once a day. The maximum dose is 45mg, taken once a day.

Will my dose go up or down?

Your doctor will check your blood sugar levels regularly. They may change your dose of pioglitazone if they need to.

What if I take too much?

The amount of pioglitazone that can lead to an overdose varies from person to person.

Urgent advice: Contact your doctor straight away if you take too much pioglitazone

If you take pioglitazone with other diabetes medicines, taking too many tablets may cause low blood sugar.

If you think you have low blood sugar, have some food or drink that quickly gets sugar into your bloodstream such as sugar cubes or fruit juice. This type of sugar won't last long in your blood. You may also need to eat a starchy carbohydrate, like a sandwich or some biscuits.

What if I forget to take it?

If you forget to take your pioglitazone, skip the missed dose and take your next dose at the usual time.

Do not take a double dose to make up for a forgotten one.

If you forget doses often, it may help to set an alarm to remind you. You could ask your pharmacist for advice on other ways to remember your medicines.

5. Side effects

Like all medicines, pioglitazone can cause side effects, although not everyone gets them.

Common side effects

These common side effects happen in more than 1 in 100 people. Talk to your doctor or pharmacist if these side effects bother you or don't go away:

  • sinus, throat or chest infections
  • problems with your eyes - your eyesight may be affected for a short time at the start of your treatment
  • putting on weight
  • pins and needles (numb fingers or toes)

Serious side effects

Some people may have serious side effects after taking pioglitazone.

Call your doctor straight away if:

  • your skin or whites of your eyes turn yellow - these can be signs of a liver problem
  • you put on weight quickly, your arms, legs or stomach are swollen, and you have problems breathing - these can be signs of heart failure
  • there's blood in your pee and you have problems peeing or need to pee urgently - these can be signs of bladder cancer

You're also at greater risk of breaking a bone when taking pioglitazone, particularly if you are a woman. If you are treated for a broken bone or fracture, let your doctor know as soon as possible afterwards.

Low blood sugar

Pioglitazone doesn't usually cause low blood sugar (known as "hypos" or hypoglycaemia) when taken on its own. However, hypos can happen when you take pioglitazone with other diabetes medicines such as insulin or gliclazide.

Early warning signs of low blood sugar include:

  • feeling hungry
  • trembling or shaking
  • sweating
  • confusion
  • difficulty concentrating

It's also possible for your blood sugar to go too low while you're asleep. If this happens, it can make you feel sweaty, tired and confused when you wake up.

Low blood sugar may happen if you:

  • take too much of some types of diabetes medicines
  • eat meals irregularly or skip meals
  • are fasting
  • don't eat a healthy diet and aren't getting enough nutrients
  • change what you eat
  • increase your physical activity without eating more to compensate
  • drink alcohol, especially after skipping a meal
  • take some other medicines or herbal medicines at the same time
  • have a hormone disorder such as hypothyroidism
  • have kidney or liver problems

To prevent hypos, it's important to have regular meals, including breakfast. Never miss or delay a meal.

If you're planning to exercise more than usual, make sure you eat carbohydrates (bread, pasta, cereals) before, during or afterwards.

Always carry a fast-acting carbohydrate with you, like sugar cubes, fruit juice or some sweets, in case your blood sugar level gets low. Artificial sweeteners won't help. You may also need to eat a starchy carbohydrate, like a sandwich or a biscuit, to maintain your blood sugar for longer.

If taking in sugar does not help or if the hypo symptoms come back, contact your doctor or the nearest hospital.

Make sure your friends and family know about your diabetes and the symptoms of low blood sugar levels so they can recognise a hypo if it happens.

Serious allergic reaction

It is possible to have a serious allergic reaction (anaphylaxis) to pioglitazone.

Immediate action required: Call 999 or go to A&E if:

  • you get a skin rash that may include itchy, red, swollen, blistered or peeling skin
  • you're wheezing
  • you get tightness in the chest or throat
  • you have trouble breathing or talking
  • your mouth, face, lips, tongue or throat start swelling

You could be having a serious allergic reaction and may need immediate treatment in hospital.

These are not all the side effects of pioglitazone. For a full list see the leaflet inside your medicines packet.


You can report any suspected side effect to the UK safety scheme.

6. How to cope with side effects

What to do about:

  • sinus, throat or chest infections – make sure you get your yearly flu jab. If you're getting a lot of infections, or you're worried, speak to your doctor.
  • problems with your eyes - do not drive or operate machinery until your eyesight is back to normal. If it lasts for more than a day or two make an appointment with your doctor.
  • putting on weight - try to eat a healthy balanced diet without increasing your portion sizes. Regular exercise will also help to keep your weight stable. If you're still putting on weight see your doctor - it may be due to fluid retention.
  • pins and needles (numb fingers or toes) - if this side effect bothers you or doesn't go away after a few days talk to your doctor.

7. Pregnancy and breastfeeding

Pioglitazone is not generally recommended in pregnancy. It's not clear whether pioglitazone can harm your unborn baby.

Talk to your doctor if you're trying for a baby, or if you find out that you're pregnant while taking pioglitazone. They will probably prescribe insulin for you instead.

Pioglitazone and breastfeeding

Pioglitazone isn't usually recommended while breastfeeding. There isn't any information to say whether it's safe or not.

Your doctor will probably recommend a different diabetes medicine while you're breastfeeding.

Non-urgent advice: Tell your doctor if you're:

  • pregnant
  • trying to get pregnant
  • breastfeeding

8. Cautions with other medicines

Some medicines interfere with the way pioglitazone works. Your doctor may need to adjust your dose of pioglitazone. They may also recommend checking your blood sugar levels more often.

Tell your doctor if you're taking any of these medicines before starting on pioglitazone:

  • gemfibrozil, a medicine used to reduce cholesterol
  • rifampicin, a medicine for treating tuberculosis

Taking pioglitazone with painkillers

It's safe to take paracetamol with pioglitazone.

Check with your doctor or pharmacist before taking ibuprofen with pioglitazone. This is particularly important if you have heart problems or if you're at risk of getting heart problems.

Mixing pioglitazone with herbal remedies and supplements

There's very little information about taking herbal remedies or supplements with pioglitazone.


For safety, tell your doctor and pharmacist if you're taking any other medicines, including herbal remedies, vitamins or supplements.

9. Common questions

How does pioglitazone work?

Pioglitazone belongs to a group of diabetes medicines called thiazolidinediones (or glitazones).

It helps control blood sugar levels by improving how your body uses a hormone called insulin. It does this by helping your cells become more sensitive to the insulin your body makes.

How long does it take to work?

Pioglitazone takes a few weeks to lower your blood sugar levels.

You won't necessarily feel any different when taking pioglitazone, as you may not have had any symptoms of diabetes. This doesn't mean that pioglitazone isn't working - and it's important to keep taking it.

Pioglitazone will help keep your blood sugar stable and reduce your chances of getting problems related to diabetes in the future.

How long will I take pioglitazone for - and can I come off it?

Treatment for diabetes is usually for life.

Do not stop taking pioglitazone without talking to your doctor.

If you stop taking pioglitazone suddenly your blood sugar levels may get worse.

If you want to stop taking your medicine, speak to your doctor. They may be able to suggest an alternative treatment for your diabetes.

Is it safe to take long term?

Pioglitazone is usually safe to take for a long time. Your doctor will give you regular tests to check whether it's OK for you to continue taking it.

Older people are slightly more likely to get some of the less common side effects of pioglitazone, such as heart failure.

Your doctor will make sure you have regular checks if they think there's a higher risk of side effects.

Does it cause 'hypos' (hypoglycaemia)?

Pioglitazone doesn't usually cause low blood sugar (known as "hypos" or hypoglycaemia) when taken on its own.

If you're taking other medicines for diabetes, your doctor may recommend reducing the dose of these other medicines when you start pioglitazone. This will reduce the risk of hypos.

Can pioglitazone cause heart failure?

Taking pioglitazone together with insulin increases your risk of heart failure. The risk is higher if you're over 65 years old.

If you already have heart failure, there's a small chance that taking pioglitazone can make it worse.

If you're unusually short of breath, put on weight quickly or have swollen legs, feet or ankles (oedema), see your doctor straight away.

Are there different types of medicine for treating diabetes?

Pioglitazone is a thiazolidinedione (also known as a glitazone). It's the only one in this group of medicines available in the UK.

There are other types of medicines that can lower blood sugar levels:

Metformin is usually the first choice of medicine used for treating type 2 diabetes. Pioglitazone can be prescribed on its own or together with other diabetes medicines such as metformin, DPP-4 inhibitors and SGLT2 inhibitors.

Your doctor will decide on the best way to treat your type 2 diabetes. They will look at your medical history and how your blood sugar levels respond to a medicine or combination of medicines.

Can I get diabetes medicines for free?

If you have diabetes, you're entitled to free prescriptions for all of your medicines (not just your diabetes ones).

To claim your free prescriptions, you'll need to have a medical exemption certificate (FP92A). You can get an application form at your GP surgery. Once you've filled in the form, ask your doctor to sign it.

Can I take pioglitazone before surgery?

You can usually take pioglitazone before surgery and on the day of surgery too - even if you're not eating (fasting).

If you're going to have an operation, tell your doctor that you're taking pioglitazone. Also tell them about any other medicines you may be taking, including other diabetes medicines.

This is because medicines for type 2 diabetes can increase your risk of low blood sugar during the operation. Low blood sugar can be difficult to detect when you're having a general anaesthetic to put you to sleep.

Your doctor may change you to insulin for a few days before your operation.

Will it affect my contraception?

Pioglitazone doesn't affect any type of contraception, including the combined pill and emergency contraception.

However, talk to your doctor before starting to take contraceptive pills if you're already taking pioglitazone. They may change your dose of pioglitazone. This is because contraceptive pills change how your body handles sugar.

Will it affect my fertility?

There's no firm evidence to suggest that taking pioglitazone will reduce fertility in either men or women.

However, speak to a pharmacist or your doctor if you're trying to get pregnant. They may want to review your treatment.

Pioglitazone can make some women with polycystic ovary syndrome (PCOS) ovulate. This can increase your chance of getting pregnant and you may need to use contraception if you're not trying for a baby.

Can I drink alcohol with it?

Yes, you can drink alcohol while taking pioglitazone. However, it's best to drink no more than 2 units a day. Drinking more than this can increase your risk of low blood sugar.

Try to keep to the recommended guidelines of no more than 14 units of alcohol a week. A standard glass of wine (175ml) is 2 units. A pint of lager or beer is usually 2 to 3 units of alcohol.

Is there any food or drink I need to avoid?

It's a good idea to cut down on foods with added sugar. Check the nutrition labels as many foods and drinks are high in sugar, such as:

  • sweets
  • cakes
  • biscuits
  • chocolate
  • some fizzy drinks
  • juice drinks

Be careful eating food and drink containing karela because it can lower your blood sugar levels and mean your diabetes isn't controlled as well as it should be.

Karela (also called bitter gourd) is used to flavour foods such as curries. It has a bitter taste and is also made into juice and tea.

Will I put on weight or lose weight?

Some people find they gain body fat when taking pioglitazone. This can make them put on weight.

Try to eat a healthy balanced diet without increasing your portion sizes, so you don't gain too much weight. Regular exercise will also help to keep your weight stable.

Pioglitazone can also make you retain water. If you put on weight, have swollen ankles, feet or legs (oedema), and have problems breathing, make an urgent appointment to see you doctor. These can be signs of heart failure.

Can I drive or ride a bike?

If your blood sugar levels are stable, then taking pioglitazone shouldn't affect your ability to drive, cycle or use machinery and tools.

However, if you take pioglitazone with other medicines for type 2 diabetes, your blood sugar levels can become too low. This can reduce your concentration. If this happens to you, do not drive, cycle, or use machines or tools, until you feel better.

If your eyesight if affected by changes in your blood sugar, do not drive or use machinery until you can see clearly again. See your doctor or optician if your vision doesn't get better.

Can lifestyle changes help?

There are some lifestyle changes you can make to help control the symptoms of diabetes. These include:

Pioglitazone is usually prescribed when diet and exercise alone have not been enough to control your blood sugar levels.