Compare Metformin vs. Actos

Head-to-head comparisons of medication uses, side effects, ratings, and more.

Glucophage
(Metformin)

Actos
(Pioglitazone)

Lowers blood sugar. Glucophage (Metformin) is a very effective medicine to lower blood sugar and the risk of complications and death from diabetes, but it's likely to cause diarrhea for the first few weeks.Lowers blood sugar. Actos (Pioglitazone) is a last-choice blood sugar-lowering medicine since it's only moderately effective but has a lot of undesirable side effects.
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Reviews & ratings
Button Group. All currently active
Button Group. All currently active
5.008611410118407Metformin
Reviews for Glucophage (Metformin)
65%
of people say Glucophage (Metformin) is worth it
46%
say it works well
16%
say it's a big hassle
Reviews for Actos (Pioglitazone)
42%
23% vs. Glucophage (Metformin)
31%
15% vs. Glucophage (Metformin)
21%
5% vs. Glucophage (Metformin)
Side effects
MetforminActos
  • Diarrhea 41%
  • Nausea/vomiting 18%
  • Passing gas 6%
  • Indigestion 3%
  • Muscle weakness 3%
  • Abdominal discomfort 1%
  • Headache 1%
More Metformin side effects »
  • Swelling due to excess fluid 11%
  • Low blood sugar 8%
  • Ear, nose, or throat infection 4%
  • Sore throat 4%
  • Cardiac failure 2%
  • Muscle pain 2%
  • Headache 2%
  • Back pain 1%
  • Sinus inflammation 1%
More Actos side effects »
How it works
MetforminActos
Glucophage (Metformin) is an anti-diabetic drug. It lowers sugar production in your body, decreases sugar absorption in your intestines, and makes your body more sensitive to insulin.Actos (Pioglitazone) is an anti-diabetic drug. It improves your body's ability to use insulin to lower your blood sugar.
Type of medication
MetforminActos
Anti-diabetic
Biguanide
Prescription only
Anti-diabetic
Thiazoladinedione
Prescription only
Available as
MetforminActos
  • Pill
  • Extended release
  • Liquid
  • Pill
Used for (click to learn more)
MetforminActos
Risk factors for serious side effects
MetforminActos
  • Kidney problems
  • Liver problems
  • Congestive heart failure
  • Using contrast dye for procedures
  • Surgery
  • Alcohol use
    Detailed Glucophage (Metformin) risks & warnings »
    • Heart failure diagnosis
      • Current liver problems
        • Female
        Detailed Actos (Pioglitazone) risks & warnings »
        Pregnancy category
        MetforminActos
        BFDA pregnancy category (Probably safe)

        Research studies with animals haven’t found a risk to unborn babies, but it hasn’t been properly studied in humans.

        See the FDA package insert
        CFDA pregnancy category (Weigh risks vs. benefits)

        Research studies with animals found harmful effects on unborn babies. It hasn’t been properly studied in humans. The benefits might outweigh the risks even if you’re pregnant. Talk with your doctor.

        See the FDA package insert
        Alcohol
        No specific alcohol-related info.No specific alcohol-related info.
        Food
        • Always take it with food or switch to the extended release version to avoid upset stomach.
        No specific food-related info.
        Kidneys and liver
        • People with poor kidney function can't use it.
        • Glucophage (Metformin) can cause this rare but life-threatening condition. Symptoms include deep and rapid breathing, nausea, vomiting, and stomach pain. This is a medical emergency and you should get help right away. Baseline blood work for kidney and liver function are helpful to see if you can use Glucophage (Metformin). It may not be a good choice for people with kidney problems. Glucophage (Metformin) should be stopped 48 hours before and/or after surgery or any imaging procedure needing contrast dye.
        No specific kidneys and liver-related info.
        Sex
        No specific sex-related info.No specific sex-related info.
        Sleep
        No specific sleep-related info.No specific sleep-related info.
        Weight
        • Unlike some diabetes medicines, doesn't cause weight gain or low blood sugar.
        • More likely to cause weight gain (2 to 6 pounds or more) compared to other blood sugar-lowering medicines.
        • Can cause weight gain, headache, and fluid retention.
        • Actos (Pioglitazone) can cause too much fluid buildup in your body, which can cause or worsen congestive heart failure. Your doctor should follow your blood tests and weight closely when you start Actos (Pioglitazone) or increase your dose. People with heart failure classification NYHA Class III/IV shouldn't use Actos (Pioglitazone).
        • Actos (Pioglitazone) may increase fluid buildup in your body, called edema. The risk increases with a higher dose. Tell your doctor about any unexpected weight gain, swelling of extremities, or trouble breathing.
        Upsides and benefits
        MetforminActos
        • A common first treatment for people with newly-diagnosed Type 2 diabetes.
        • The only oral diabetes medicine that lowers complications and deaths from conditions related to diabetes.
        • Lowers A1c levels by 1-2%. (Hemoglobin A1c measures your average blood sugar over time.)
        • Also lowers certain lipid (fat and cholesterol) levels.
        • Unlike some diabetes medicines, doesn't cause weight gain or low blood sugar.
        • You don't have to check your blood sugar every day with this medicine.
        • One of the least expensive diabetes medicines.
        • Oral blood sugar-lowering medicine.
        • Prevents the harmful effects of high sugar levels on your organs and blood vessels.
        • Lowers A1c levels by around 1%. (Hemoglobin A1c measures your average blood sugar over time.)
        • Rarely causes low blood sugar.
        • Oral blood sugar-lowering medicine.
        • Prevents the harmful effects of high sugar levels on your organs and blood vessels.
        Downsides and risks
        MetforminActos
        • Most people will have nausea, indigestion, or diarrhea in the first few weeks. You can minimize this if you take it on a full stomach.
        • People with poor kidney function can't use it.
        • Only works if your body can still make your own insulin, a hormone that tells your body what to do with sugar, protein, and fat.
        • May take several weeks to lower blood sugar.
        • You have to check your blood sugar regularly with this medicine.
        • Has more side effects than similar medicines, so it's usually not the first choice for new Type 2 diabetes patients.
        • More likely to cause weight gain (2 to 6 pounds or more) compared to other blood sugar-lowering medicines.
        • Up to 1 in 10 people might get fluid retention (edema), ranging from mild ankle swelling to severe swelling in the lungs that makes it hard to breathe. People with severe congestive heart failure shouldn't use Actos.
        • Raises the risk of bone fractures, especially for people who already have a risk for fractures.
        • Slightly raises the risk of bladder cancer.
        Tips from our pharmacists for people taking the medication
        MetforminActos
        • Can cause upset stomach with nausea and especially diarrhea in the first couple of weeks.
        • Always take it with food or switch to the extended release version to avoid upset stomach.
        • Tell your doctor about any deep or rapid breathing, or persistent nausea, vomiting, and stomach pain.
        • Check your blood sugar regularly.
        • Takes several weeks to see full effect on blood sugar control.
        • Can cause weight gain, headache, and fluid retention.
        • Tell your doctor about any mental confusion, persistent abdominal pain, dark urine, yellowing of eyes/skin, or easy bruising.
        • Not recommended for patients with certain heart problems.
        • Check your blood sugar regularly.
        Learn more
        More about MetforminSide effectsReviews & ratingsAlternativesFDA package insert
        More about ActosSide effectsReviews & ratingsAlternativesFDA package insert