Pioglitazone is a member of the family of medications known as thiazolidinediones. It is used to lower high blood sugar associated with type 2 diabetes. Thiazolidinediones such as pioglitazone help insulin to work more effectively. By keeping blood sugar at a desired level, pioglitazone can help to prevent or delay the long-term problems associated with uncontrolled high blood sugar (e.g., kidney disease, eye problems, nerve problems, heart disease). Pioglitazone may be used alone when blood sugar is not controlled only by diet and exercise or in combination with one other diabetes medication, including metformin and the sulfonylureas (e.g., glyburide, gliclazide).

Pioglitazone should start lowering your blood sugar shortly after you begin taking it. The maximum lowering of blood sugar due to pioglitazone usually occurs about 14 weeks after starting it.

This medication may be available under multiple brand names and/or in several different forms. Any specific brand name of this medication may not be available in all of the forms or approved for all of the conditions discussed here. As well, some forms of this medication may not be used for all of the conditions discussed here.

Your doctor may have suggested this medication for conditions other than those listed in these drug information articles. If you have not discussed this with your doctor or are not sure why you are taking this medication, speak to your doctor. Do not stop taking this medication without consulting your doctor.

Do not give this medication to anyone else, even if they have the same symptoms as you do. It can be harmful for people to take this medication if their doctor has not prescribed it.

The usual starting dose for adults is 15 mg or 30 mg taken once daily. Diet and exercise programs should be continued while taking pioglitazone. Your doctor may decide to increase the dose of pioglitazone to 45 mg daily if lower doses do not sufficiently reduce your blood sugar levels.

Pioglitazone may be taken with or without food. It should be taken daily and at regular intervals as prescribed by the doctor, so that blood levels of the medication always remain in an effective range.

Many things can affect the dose of medication that a person needs, such as body weight, other medical conditions, and other medications. If your doctor has recommended a dose different from the ones listed here, do not change the way that you are taking the medication without talking to your doctor.

It is important to take this medication exactly as prescribed by your doctor. If you miss a dose, take it as soon as possible and continue with your regular schedule. If it is almost time for your next dose, skip the missed dose and continue with your regular dosing schedule. Do not take a double dose to make up for a missed one. If you are not sure what to do after missing a dose, contact your doctor or pharmacist for advice.

Store this medication at room temperature, protect it from light and moisture, and keep it out of the reach of children.

Do not take this medication if you:

• are allergic to pioglitazone or any ingredients of this medication
• are pregnant
• have been diagnosed with any stage of heart failure
• have blood or a red colour in your urine
• have or have had bladder cancer
• have reduced liver function

Many medications can cause side effects. A side effect is an unwanted response to a medication when it is taken in normal doses. Side effects can be mild or severe, temporary or permanent.

The side effects listed below are not experienced by everyone who takes this medication. If you are concerned about side effects, discuss the risks and benefits of this medication with your doctor.

The following side effects have been reported by at least 1% of people taking this medication. Many of these side effects can be managed, and some may go away on their own over time.

Contact your doctor if you experience these side effects and they are severe or bothersome. Your pharmacist may be able to advise you on managing side effects.

• dizziness
• hunger
• lack of energy
• shakiness
• sweating
• weight gain

Although most of the side effects listed below don't happen very often, they could lead to serious problems if you do not seek medical attention.

Check with your doctor as soon as possible if any of the following side effects occur:

• blurred vision due to swelling (or fluid) in the back of the eye
• fractures, usually in the hand, upper arm, or foot
• liver problems:
• dark urine
• lack of appetite
• nausea
• stomach pain
• tiredness
• vomiting
• yellowing of the skin
• problems with teeth
• signs of anemia (low red blood cells; e.g., dizziness, pale skin, unusual tiredness or weakness, shortness of breath)
• signs of heart failure (e.g., breathlessness, fatigue easily, sudden weight gain, difficulty breathing, leg swelling)
• swelling of the feet or lower legs, hands, or wrists
• rapid weight gain
• unexpected or unusual menstrual bleeding

Stop taking the medication and seek immediate medical attention if any of the following occur:

• swelling of the face, lips, mouth, tongue, or throat (may cause difficulty in swallowing or breathing); hives or rash (which may be itchy)
• symptoms of bladder cancer (e.g., red colour or blood in the urine, increased need to urinate or pain while urinating)

Some people may experience side effects other than those listed. Check with your doctor if you notice any symptom that worries you while you are taking this medication.

You should be aware of the signs of low blood sugar and what to do about it when taking any medication that reduces your blood sugar, including pioglitazone. Signs of low blood sugar include:

• anxiety
• behaviour change similar to being drunk
• blurred vision
• cold sweats
• confusion
• continuous headache
• cool and pale skin
• difficulty thinking
• drowsiness
• excessive hunger
• fast heartbeat
• nausea
• nervousness
• shakiness
• slurred speech
• unusual tiredness or weakness

If you experience symptoms of low blood sugar, eat glucose tablets or gel, corn syrup, honey, or sugar cubes, or drink juice or a non-diet soft drink, as discussed with your doctor or diabetes educator.

Before you begin taking a medication, be sure to inform your doctor of any medical conditions or allergies you may have, any medications you are taking, whether you are pregnant or breast-feeding, and any other significant facts about your health. These factors may affect how you should take this medication.

Bladder: Taking pioglitazone may increase the risk of developing bladder cancer. If you have risk factors for bladder cancer, such as age, smoking, or someone in your family has had bladder cancer you may be more likely to develop this disease. Do not use this medication if you have or have had bladder cancer.

If you experience symptoms such as blood or red colour in your urine, an urgent need to urinate, pain while urinating, or pain in the back or lower abdomen, talk to your doctor right away.

Fractures: Pioglitazone has been associated with an increased incidence of bone fracture for female patients. You and your doctor should consider the risk of fractures. Talk to your doctor if you have any concerns.

Heart failure: Pioglitazone can cause fluid buildup in the body, which may lead to congestive heart failure. This medication should not be used by anyone who has any degree of heart failure, or anyone who is at risk of heart failure (including people with swelling due to fluid buildup). If you develop fluid buildup or swelling, shortness of breath, fatigue, or excessive weight gain while taking this medication, you should consult your doctor immediately.

Liver: Although liver problems have not been observed with pioglitazone, another similar medication has caused liver problems in a small number of people. You should report any signs of liver problems (abdominal or stomach pain, dark urine, loss of appetite, nausea or vomiting, unusual tiredness or weakness, or yellow eyes or skin) to your doctor at once.

Use with other diabetes medications: Pioglitazone should not be used with insulin. It should not be used in combination (i.e., triple therapy) with both metformin and a sulfonylurea (e.g., glyburide, gliclazide); however, it may be used with either metformin or a sulfonylurea.

Vision: Pioglitazone may cause fluid to build up in the eye (macular edema) causing vision changes. If you experience any change to your vision, contact your doctor.

Pregnancy: Pioglitazone has not been studied for use by pregnant women. This medication should not be used during pregnancy. In general, blood sugar should be controlled during pregnancy by using insulin injections. If you become pregnant while taking this medication, contact your doctor immediately.

Breast-feeding: It is not known if pioglitazone passes into breast milk. If you are a breast-feeding mother and are taking this medication, it may affect your baby. Talk to your doctor about whether you should continue breast-feeding.

Children: The safety and effectiveness of using this medication have not been established for children.

There may be an interaction between pioglitazone and any of the following:

• abiraterone acetate
• acetylsalicylic acid (ASA)
• androgens (e.g., testosterone)
• atypical antipsychotics (e.g., clozapine, olanzapine, quetiapine, risperidone)
• beta-blockers (e.g., acebutolol, atenolol, metoprolol)
• birth control pills
• clopidogrel
• corticosteroids (e.g., dexamethasone, hydrocortisone, prednisone)
• deferasirox
• diabetes medications (e.g., acarbose, canagliflozin, glyburide, insulin, linagliptin, lixisenatide, metformin)
• disopyramide
• diuretics (water pills; e.g., furosemide, hydrochlorothiazide, triamterene)
• estrogens (e.g., conjugated estrogen, estradiol, ethinyl estradiol)
• everolimus
• gemfibrozil
• glucagon
• hepatitis C antivirals (e.g., elbasvir, grazoprevir, sofosbuvir, velpatasvir, voxilaprevir)
• HIV protease inhibitors (e.g., atazanavir, indinavir, ritonavir, saquinavir)
• hydroxychloroquine
• lanreotide
• mifepristone
• monoamine oxidase inhibitors (MAOIs; e.g., moclobemide, phenelzine, rasagiline, selegiline, tranylcypromine)
• octreotide
• pasireotide
• pentamidine
• pegvisomant
• pregabalin
• progestins (e.g., dienogest, levonorgestrel, medroxyprogesterone, norethindrone)
• protein kinase inhibitors (e.g., ceritinib, loratinib, nilotinib, sunitinib)proton pump inhibitors (e.g., lansoprazole, omeprazole, pantoprazole)
• quinolone antibiotics (e.g., ciprofloxacin, norfloxacin)
• rifampin
• selective serotonin reuptake inhibitors (SSRIs; e.g., citalopram, fluoxetine, paroxetine, sertraline)
• sirolimus
• somatostatin acetate
• somatropin
• sulfamethoxazole
• tacrolimus
• tramadol
• trimethoprim

If you are taking any of these medications, speak with your doctor or pharmacist. Depending on your specific circumstances, your doctor may want you to:

• stop taking one of the medications,
• change one of the medications to another,
• change how you are taking one or both of the medications, or
• leave everything as is.

An interaction between two medications does not always mean that you must stop taking one of them. Speak to your doctor about how any drug interactions are being managed or should be managed.

Medications other than those listed above may interact with this medication. Tell your doctor or prescriber about all prescription, over-the-counter (non-prescription), and herbal medications you are taking. Also tell them about any supplements you take. Since caffeine, alcohol, the nicotine from cigarettes, or street drugs can affect the action of many medications, you should let your prescriber know if you use them.