Actos Side Effects

Generic Name: pioglitazone

Note: This page contains information about the side effects of pioglitazone. Some of the dosage forms included on this document may not apply to the brand name Actos.

Not all side effects for Actos may be reported. You should always consult a doctor or healthcare professional for medical advice. Side effects can be reported to the FDA here.

For the Consumer

Applies to pioglitazone: oral tablet

In addition to its needed effects, some unwanted effects may be caused by pioglitazone (the active ingredient contained in Actos). In the event that any of these side effects do occur, they may require medical attention.

You should check with your doctor immediately if any of these side effects occur when taking pioglitazone:

More common
  • Chest pain
  • decreased urine output
  • dilated neck veins
  • extreme fatigue
  • irregular breathing
  • irregular heartbeat
  • problems with teeth
  • shortness of breath
  • swelling of the face, fingers, feet, or lower legs
  • tightness in the chest
  • trouble with breathing
  • weight gain
  • wheezing
Less common
  • Pain or swelling in the arms or legs without an injury
  • pale skin
  • swelling
  • trouble with breathing when active
  • unusual bleeding or bruising
  • unusual tiredness or weakness
Incidence not known
  • Dark urine
  • loss of appetite
  • nausea or vomiting
  • stomach pain
  • unexplained, rapid weight gain
  • yellow eyes or skin

Some of the side effects that can occur with pioglitazone may not need medical attention. As your body adjusts to the medicine during treatment these side effects may go away. Your health care professional may also be able to tell you about ways to reduce or prevent some of these side effects. If any of the following side effects continue, are bothersome or if you have any questions about them, check with your health care professional:

More common
  • Blurred vision or other changes in vision
  • cough
  • dry mouth
  • flushed, dry skin
  • fruit-like breath odor
  • headache
  • increased hunger
  • increased thirst
  • increased urination
  • loss of consciousness
  • muscle pain or soreness
  • problems with your teeth
  • runny or stuffy nose
  • sore throat
  • stomachache
  • sweating
  • unexplained weight loss

For Healthcare Professionals

Applies to pioglitazone: oral tablet


The types of side effects reported when pioglitazone (the active ingredient contained in Actos) was used in combination with sulfonylurea, metformin or insulin were generally similar to those reported during pioglitazone monotherapy with the exception of an increase in the occurrence of edema in the insulin combination study.

Pioglitazone has been generally well tolerated with the incidence of adverse effects similar to placebo. Upper respiratory tract infections, headache, sinusitis, myalgia, tooth disorder and pharyngitis were reported slightly more frequently than placebo in clinical trials.


Endocrine side effects have included mild to moderate hypoglycemia which was reported during combination therapy with a sulfonylurea or insulin.


Hematologic side effects have included anemia which was reported in 1% of pioglitazone (the active ingredient contained in Actos) patients and none of the placebo patients. Pioglitazone may cause decreases in hemoglobin and hematocrit. Across all clinical studied, mean hemoglobin values declined by 2 to 4%. Anemia was reported more frequently when pioglitazone was combined with insulin, a sulfonylurea or metformin.


A case of angioneurotic edema, characterized as a sore throat followed by dyspnea and swelling of the lips and tongue, has been reported.

Cardiovascular side effects have included edema which was reported in 4.8% of pioglitazone patients versus 1.2% of placebo patients. In combination studies, edema was reported for 7.2% of patients treated with pioglitazone and sulfonylureas compared to 2.1% of patients on sulfonylureas alone. In combination therapy studies with metformin, edema was reported in 6.0% of patients on combination therapy compared to 2.5% of patients on metformin alone. In combination therapy studies with insulin, edema was reported in 15.3% of patients on combination therapy compared to 7.0% of patients on insulin alone.


Hepatic side effects have included reports of liver damage associated with pioglitazone (the active ingredient contained in Actos) therapy.


Ocular side effects have included postmarketing reports of new onset or worsening diabetic macular edema with decreased visual acuity.

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