Actos (Pioglitazone) - Oral


Actos (pioglitazone) has a boxed warning, the strongest warning required by the Food and Drug Administration (FDA), for the following risks associated with its use.

Actos can cause or worsen heart failure in some people. After starting Actos and any changes in dose, watch for heart failure symptoms, such as fast weight gain, swelling, and shortness of breath.

People with heart failure who have symptoms of NYHA Class III or IV heart failure should not take Actos.

What Is Actos?

Actos (pioglitazone) is an oral prescription antidiabetic medication. When used along with diet and exercise, it improves blood sugar control in adults with type 2 diabetes.

Actos is in a drug class known as thiazolidinediones. Drugs in this category are also sometimes referred to as glitazones. This medication decreases blood glucose (sugar) levels by improving the body’s sensitivity to insulin.

Actos contains the ingredient pioglitazone. It is available in both brand name and generic form as a tablet.

Drug Facts

Generic Name: Pioglitazone

Brand Name(s): Actos

Drug Availability: Prescription

Administration Route: Oral

Therapeutic Classification: Hypoglycemic

Available Generically: Yes

Controlled Substance: N/A

Active Ingredient: Pioglitazone

Dosage Form(s): Tablet

What Is Actos Used For?

The Food and Drug Administration (FDA) approved Actos for blood sugar control in adults with type 2 diabetes. It should not be used for type 1 diabetes, another form of diabetes in which insulin production decreases, or diabetic ketoacidosis, a complication of diabetes.

While it can help manage your condition, Actos is not a cure. To achieve optimal blood sugar control, you must take this medication as prescribed and combine it with diet and exercise.

How to Take Actos

Read the patient information leaflet that comes with your Actos prescription. Before starting treatment, talk to your healthcare provider or pharmacist if you have questions.

Actos is usually taken once daily. You can take it with or without food. Do not change the dose unless your healthcare provider tells you to do so.

Follow your healthcare provider’s instructions on other measures such as diet, exercise, and blood sugar testing. Your healthcare provider will tell you how often to check your blood sugar. Try to document your blood sugar findings so you can report them at your next healthcare visit.

If you take Actos in combination with other oral medications for diabetes or insulin injections, you may be more likely to develop low blood sugar (hypoglycemia). Low blood sugar can cause you to feel shaky, hungry, dizzy, or cranky. To treat low blood sugar, your healthcare provider may advise you to take fast-acting glucose tablets or drink a small amount of apple juice.

You may also be prescribed glucagon to be used in case of a severe low blood sugar emergency. Glucagon is available as an injection or nasal spray (the nasal spray is called Baqsimi). You can educate your family and close friends on how to administer glucagon in an emergency situation.


Store Actos at room temperature (between 68 F and 77 F), away from heat, direct light, and moisture. Keep the medication in its original labeled container and out of the reach of children and pets. The bottle should be kept tightly closed when not in use.

How Long Does Actos Take to Work?

When you take a dose of Actos, the drug reaches its maximum levels in the body in about two hours. It may take about two weeks for your blood sugar to decrease, and up to three months to see the full effect of Actos.

What Are the Side Effects of Actos?

This is not a complete list of side effects, and others may occur. A healthcare provider can advise you on side effects. If you experience other effects, contact your healthcare provider. You may report side effects to the FDA at or 1-800-FDA-1088.

Like other medications, Actos may cause side effects. Let your healthcare provider know about any side effects you experience while taking this medication.

Common Side Effects

The most common side effects of Actos are:

  • Flatulence (gas)
  • Headache 
  • Muscle pain
  • Ovulation induction, which is when you ovulate (release a mature egg from the ovaries), even if you normally do not, and can result in pregnancy
  • Sore throat 
  • Swelling/fluid retention 
  • Upper respiratory tract infection/sinus infection
  • Weight gain

Severe Side Effects

Call your healthcare provider immediately if you have serious side effects. Call 911 if your symptoms feel life-threatening or if you think you’re having a medical emergency. Serious side effects and symptoms such as:

  • Congestive heart failure (CHF): Symptoms may include weight gain, shortness of breath, and swelling. CHF is more common in patients who take both Actos and insulin.
  • Diabetic macular edema: This serious complication can cause vision problems or blindness.
  • Bone fractures sometimes occur in older females.
  • Hypersensitivity: Symptoms may include hives, trouble breathing, and swelling of the lips, face, tongue, or throat, and require emergency medical attention.
  • Increased risk of bladder cancer: Symptoms can include painful or difficult urination.
  • Liver problems: Symptoms may include pain, appetite loss, fatigue, and yellowing of the skin or whites of the eyes.

Long-Term Side Effects

While Actos is often well tolerated, long-term effects are possible. These adverse effects may be delayed or can cause lasting health complications.

Long-term side effects can be mild, like:

  • Weight gain
  • Back pain
  • Sinus infection
  • Sore throat
  • Appetite loss
  • Menstrual irregularities (which can increase the chance of pregnancy)

Moderate long-term side effects can include:

  • Swelling 
  • Anemia
  • Liver problems
  • Bone loss, which can increase the risk of bone fractures

Severe long-term side effects may include: 

  • Heart failure
  • Bone fractures
  • Liver failure
  • Hepatic encephalopathy (brain abnormalities due to liver disease)
  • Vision problems or blindness
  • Cancer
  • Rhabdomyolysis (a life-threatening condition caused by muscle breakdown and muscle death)

Report Side Effects

Actos may cause other side effects. Call your healthcare provider if you have any unusual problems while taking this medication.

If you experience a serious side effect, you or your healthcare provider may send a report to the FDA's MedWatch Adverse Event Reporting Program or by phone (800-332-1088).

Dosage: How Much Actos Should I Take?

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The dose of this medicine will be different for different patients. Follow your doctor's orders or the directions on the label. The following information includes only the average doses of this medicine. If your dose is different, do not change it unless your doctor tells you to do so.

The amount of medicine that you take depends on the strength of the medicine. Also, the number of doses you take each day, the time allowed between doses, and the length of time you take the medicine depend on the medical problem for which you are using the medicine.

  • For oral dosage form (tablets):
    • For type 2 diabetes:
      • Adults—At first, 15 or 30 milligrams (mg) once a day. Your doctor may adjust your dose as needed. However, the dose is usually not more than 45 mg once a day.
      • Children—Use and dose must be determined by your doctor.


You may need to use caution when taking Actos if you are 65 years or older, especially if you have heart or kidney problems. Heart or kidney problems can increase your risk of fluid retention and heart failure. Your healthcare provider may monitor you while you are taking Actos and stop the medication if heart problems occur.

Actos can also induce ovulation if you are of reproductive potential and do not have monthly periods. This can increase the chance of pregnancy. If you are pregnant or plan to become pregnant, talk to your healthcare provider before taking Actos. If you are taking Actos and find out you are pregnant, contact your healthcare provider immediately for medical advice.

There is no human data about Actos and breastfeeding. Consult your healthcare provider before breastfeeding while taking Actos.

Missed Dose

If you miss a dose of Actos, take it as soon as you can. Do not take two doses together.

Overdose: What Happens If I Take Too Much Actos?

Taking too much Actos can cause hypoglycemia (low blood sugar).

Symptoms of hypoglycemia can include:

  • Weakness 
  • Blurry vision
  • Sweating
  • Tremors
  • Difficulty speaking
  • Stomach pain
  • Confusion
  • Seizures

What Happens If I Overdose on Actos?

If you think you or someone else may have overdosed on Actos, call a healthcare provider or the Poison Control Center (800-222-1222).

If someone collapses or isn't breathing after taking Actos, call 911 immediately.


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It is very important that your doctor check your progress at regular visits to make sure that this medicine is working properly and to decide if you should continue to use it. Blood and urine tests may be needed to check for unwanted effects.

This medicine may cause some women who do not have regular monthly periods to ovulate. This can increase the chance of pregnancy. If you are a woman of childbearing potential, you should discuss birth control options with your doctor.

If you are rapidly gaining weight, having shortness of breath, chest pain or discomfort, extreme tiredness or weakness, irregular breathing, irregular heartbeat, or excessive swelling of the hands, wrist, ankles, or feet, check with your doctor immediately. These may be symptoms of a serious heart problem.

If you have abdominal or stomach pain, dark urine, a loss of appetite, nausea or vomiting, unusual tiredness or weakness, or yellow eyes or skin, check with your doctor right away. These may be symptoms of a serious liver problem.

Check with your doctor right away if blurred vision, decreased vision, or any other change in vision occurs while you are taking this medicine. Your doctor may want you to have your eyes checked by an ophthalmologist (eye doctor).

This medicine may increase the risk for bone fractures in women. Ask your doctor about ways to keep your bones strong to help prevent fractures.

This medicine may increase your risk for bladder cancer if you take it for more than 12 months. Tell your doctor right away if you have blood in the urine, a frequent, strong, or increased urge to urinate, painful urination, or pain in the back, lower abdomen, or stomach.

This medicine can cause hypoglycemia (low blood sugar). However, low blood sugar can occur if you delay or miss a meal or snack, exercise more than usual, drink alcohol, cannot eat because of nausea or vomiting, or take certain medicines. Low blood sugar must be treated before it causes you to pass out (unconsciousness). People feel different symptoms of low blood sugar. It is important that you learn which symptoms you have in order to treat it quickly. Talk to your doctor about the best way to treat low blood sugar.

Hyperglycemia (high blood sugar) may occur if you do not take enough or skip a dose of your medicine, overeat or do not follow your meal plan, have a fever or infection, or do not exercise as much as usual. High blood sugar can be very serious and must be treated right away. It is important that you learn which symptoms you have in order to treat it quickly. Talk to your doctor about the best way to treat high blood sugar.

There may be a time when you need emergency help for a problem caused by your diabetes. You need to be prepared for these emergencies. It is a good idea to wear a medical identification (ID) bracelet or neck chain at all times. Also, carry an ID card in your wallet or purse that says you have diabetes with a list of all your medicines.

Do not take other medicines unless they have been discussed with your doctor. This includes prescription or nonprescription (over-the-counter [OTC]) medicines and herbal or vitamin supplements.

What Are Reasons I Shouldn’t Take Actos?

Actos is not appropriate for everyone. You should not take this medication if allergic to pioglitazone or any inactive ingredients in Actos.

Other people who should not take Actos include:

  • Children and teenagers under 18
  • People with NYHA Class III or IV heart failure or heart failure with symptoms (such as shortness of breath, fatigue, and leg swelling)
  • People with type 1 diabetes
  • People with diabetic ketoacidosis
  • People with bladder cancer

Actos may be prescribed with caution in some cases only if the healthcare provider determines it is safe. This includes people:

  • At risk of heart failure
  • With NYHA Class I or II heart failure
  • With edema (swelling)
  • With liver problems
  • With a history of bladder cancer 
  • Who are of childbearing age and do not ovulate (Actos can cause ovulation, increasing the chance of pregnancy)

What Other Medications May Interact With Actos?

Tell your healthcare provider about all of the medicines you take, including prescription and over-the-counter (OTC) medicines, and vitamins or supplements.

Medications that commonly interact with Actos include:

  • Insulin or other medications that lower blood sugar: Taking these along with Actos can increase the risk of low blood sugar. A dosage adjustment may be required.
  • Lopid (gemfibrozil): This combination increases Actos levels in the body. If you must take these drugs together, your healthcare provider may prescribe Actos at its lowest dose of 15 milligrams (mg) daily.
  • Rifampin: Rifampin decreases Actos levels in the body, which can make Actos less effective. A dosage adjustment of Actos may be required.
  • Topiramate: Topiramate can also decrease Actos levels in the body. If you take these drugs together, your healthcare provider may monitor your blood sugar control.

Additionally, try to avoid alcohol while taking Actos. Alcohol can lower blood sugar and interfere with your treatment.

Other examples of drugs that may interact with Actos include:

Other interactions may occur with Actos. Consult your healthcare provider for a full list of drug interactions.

What Medications Are Similar?

Actos is currently the only drug in the thiazolidinedione drug class. Rezulin (troglitazone) and Avandia (rosiglitazone) are thiazolidinedione drugs removed from the market that are no longer available.

Besides Actos, various oral medications are available to help control blood sugar in adults with type 2 diabetes, including:

A drug class that is becoming very popular for people with type 2 diabetes is a category known as glucagon-like peptide-1 (GLP-1) receptor agonists. These drugs are not insulin but help the pancreas release insulin, prevent the liver from making too much sugar, and slow down food leaving the stomach.

GLP-1 receptor agonists include the oral drug Rybelsus (semaglutide) and the following injectable drugs: 

People with type 2 diabetes may also need injectable insulin to help control blood sugar. There are several types of long-acting (e.g., Lantus and Levemir) and short-acting (e.g., Humalog and Novolog) insulin.

This is a list of drugs also prescribed for type 2 diabetes. It is NOT a list of drugs recommended to take with pioglitazone. Talk to your pharmacist or a healthcare provider if you have questions.

Frequently Asked Questions

  • What is Actos used for?

    Actos is used to help control blood sugar in adults with type 2 diabetes. However, it does not cure diabetes. Therefore, you must also adhere to a diet and exercise plan to help improve blood sugar. Actos should also not be used in type 1 diabetes or diabetic ketoacidosis.

  • How does Actos work?

    Actos increases the body’s sensitivity to insulin and helps control blood sugar levels.

  • What drugs should not be taken with Actos?

    Several different medications can interact with Actos. Taking insulin or other blood-sugar-lowering drugs can enhance the risk of extremely low blood sugar. You may need to be extra careful while taking these medications together. Other drugs that interact with Actos include gemfibrozil, rifampin, and topiramate. Tell your healthcare provider about all the medications you take before starting Actos.

  • How long does it take for Actos to work?

    Your blood sugar will start to decrease as soon as two weeks after starting treatment. However, it may take two or three months to reach the maximum effect.

  • What are the side effects of Actos?

    The most common side effects of Actos are headache, muscle pain, gas, sore throat, swelling, weight gain, and sinus infection or upper respiratory tract infection. Actos can also cause women of reproductive potential to ovulate when they normally do not ovulate, which can increase the likelihood of pregnancy.

    In rare cases, Actos can cause serious side effects such as heart failure, vision problems or blindness, fractures (in older females), liver problems, and an increased risk of bladder cancer. If you have signs of an allergic reaction, such as trouble breathing, hives, or swelling of the face, lips, tongue, or throat, get emergency medical help right away.

  • What is the boxed warning on Actos?

    Actos has a boxed warning, which states that:

    • Actos can cause or worsen heart failure in some people.
    • People should be monitored for heart failure after starting Actos and after any changes in dose. 
    • People with NYHA Class III or IV heart failure or symptoms of heart failure should not take Actos.

    A boxed warning is the strictest warning label required by the FDA.

  • How do I stop taking Actos?

    Your healthcare provider will advise you on how long to take Actos. Do not stop taking the medication without medical guidance.

How Can I Stay Healthy While Taking Actos?

Before taking Actos, discuss your medical history and all medication you take with your healthcare provider.

When taking Actos, follow your healthcare provider’s instructions for use. Read the patient information leaflet that comes with your prescription.

Prepare a diabetes kit to keep on hand, with supplies such as:

  • A blood glucose testing meter and plenty of supplies (e.g., strips, lancing device, lancets, alcohol wipes)
  • Emergency contact information
  • Glucagon (injection or nasal Baqsimi)
  • Treatments for low blood sugar such as glucose tablets and juice boxes

Wear a medical alert bracelet or necklace at all times. This alerts emergency responders that you have type 2 diabetes.

Actos should be used along with diet and exercise. Talk to your healthcare provider about what kind of diet and exercise regimen you should follow and monitor your blood sugar regularly.

Medical Disclaimer

Verywell Health's drug information is meant for educational purposes only and is not intended to replace medical advice, diagnosis, or treatment from a healthcare provider. Consult your healthcare provider before taking any new medication(s). IBM Watson Micromedex provides some of the drug content, as indicated on the page.

5 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. DailyMed. Label: Actos- pioglitazone hydrochloride tablet.

  2. Schernthaner G, Currie CJ, Schernthaner GH. Do we still need pioglitazone for the treatment of type 2 diabetes? A risk-benefit critique in 2013. Diabetes Care. 2013;36 Suppl 2(Suppl 2):S155-161. doi:10.2337/dcS13-2031

  3. MedlinePlus. Pioglitazone.

  4. Prescribers’ Digital Reference. Pioglitazone - drug summary.

  5. Andreasen CR, Andersen A, Knop FK, Vilsbøll T. How glucagon-like peptide 1 receptor agonists work. Endocr Connect. 2021;10(7):R200-R212. doi:10.1530/EC-21-0130

By Karen Berger, PharmD
Karen Berger, PharmD, is a community pharmacist and medical writer/reviewer.