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Compare Propylthiouracil vs. Methimazole

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

  • Propylthiouracil
    Methimazole
  • Propylthiouracil
    Methimazole

  • Summary of Propylthiouracil vs. Methimazole

    Summary for Antithyroid
    Prescription only

    Propylthiouracil is used to treat an overactive thyroid (also known as hyperthyroidism). The medication is typically used if you can't tolerate methimazole or are preparing to undergo surgery. It can cause serious, life-threatening liver damage with symptoms that you need to look out for (e.g., itchiness and upper right abdominal pain). Other possible side effects include nausea, rash, joint pain, and loss of taste. Propylthiouracil is a first-choice treatment option during pregnancy, but shouldn't be used after the first trimester due to the risk of harm to mothers and unborn babies.

    Summary for Antithyroid agent
    Prescription only

    Methimazole is used to treat hyperthyroidism, which happens when your thyroid makes more thyroid hormones than what the body needs. This medication is a tablet that’s taken by mouth. Common side effects include rash, drowsiness, and headache. Methimazole isn’t recommended for use in the first trimester of pregnancy, but it’s the preferred option during the second and third trimesters. While it doesn’t have a brand name on the market currently, there’s a lower-cost generic version available.

  • Indications of Propylthiouracil vs. Methimazole

    Indications for
    •High thyroid hormone levels (hyperthyroidism) in people:
    •With Graves’ disease or other medical conditions who can’t take methimazole, receive thyroid surgery, or radioactive iodine treatment
    •Who are preparing to undergo thyroid surgery or radioactive iodine treatment
    Indications for

    High thyroid hormone levels (hyperthyroidism) in people:

    •With Graves’ disease or other medical conditions who can’t receive thyroid surgery or radioactive iodine treatment
    •Who are preparing to undergo thyroid surgery or radioactive iodine treatment

  • Pros and Cons of Propylthiouracil vs. Methimazole

    Pros and Const for Antithyroid
    Pros
    •Can be used during the first three months of pregnancy
    •First-choice medication for treating thyroid storm (life-threatening thyroid problem)
    •Available as a lower-cost generic
    Cons
    •Must be taken three times a day
    •More serious side effects than methimazole, like potential liver damage
    •Can raise your chance of infections
    Pros and Const for Antithyroid agent
    Pros
    •Maintenance dosing is once a day
    •Lower-cost therapy since it’s only available as generic on the market
    •May work better than propylthiouracil (PTU) to improve thyroid hormone levels
    •Less likely to cause serious liver damage compared to other antithyroid medications
    Cons
    •Need to get blood tests often to check thyroid hormone levels for dosage adjustments
    •May lower your body’s ability to fight infections
    •May increase your risk of bleeding
    •Unsafe to use during the first trimester of pregnancy

  • Common Side Effects of Propylthiouracil vs. Methimazole

    Common Side Effects for
    •Nausea
    •Vomiting
    •Upper stomach pain or tenderness
    •Joint pain
    •Itching
    •Tingling sensation
    •Loss or change in taste
    •Loss of hair
    •Muscle pain
    •Headache
    •Nerve pain
    •Swelling (edema)
    •Dizziness
    Common Side Effects for

    Up to 10% of people taking this medication have reported the following side effects:

    •Raised, itchy rash
    •Nausea
    •Vomiting
    •Stomach upset

  • Warnings of Propylthiouracil vs. Methimazole

    Common Side Effects for
    •Liver damage
    •Harm to unborn babies
    •Weakened immune system
    •Low thyroid levels (hypothyroidism)
    •Blood vessel problems
    Common Side Effects for
    •Harm to unborn baby during the first trimester of pregnancy
    •Low white blood cell count (agranulocytosis)
    •Liver damage
    •Low levels of thyroid hormone (hypothyroidism)
    •Thickening of blood vessels (vasculitis)

  • Prices with our coupons for Propylthiouracil vs. Methimazole

    Learn more about Propylthiouracil
    Learn more about Methimazole

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