What is Propylthiouracil: Uses, Warnings & Interactions

Updated Jan 13, 2021  •  Published Dec 30, 2020

Propylthiouracil overview

Generic Names:

  • Propylthiouracil

Uses:

  • Treats Graves' disease and hyperthyroidism (too much thyroid hormone from the thyroid gland) in patients who have already been treated with other medicines (such as methimazole) that did not work well.

Therapeutic Classes:

  • Antithyroid Agent

Forms:

  • Tablet

How it’s taken:

  • By mouth

What form(s) does Propylthiouracil come in

  • Tablet

What are common Propylthiouracil doses?

  • Tablet 50MG

Common Propylthiouracil prescriptions

  • Propylthiouracil
    50mg tablet

How to take Propylthiouracil

  • Your doctor will tell you how much medicine to use. Do not use more than directed.

  • It is best to take propylthiouracil at the same time each day. If you take more than one tablet every day, try to take the medicine at evenly spaced intervals, such as every 12 hours if you take it two times a day, or every 8 hours if you take it three times a day.

  • It is best to take propylthiouracil at the same time each day. If you take more than one tablet every day, try to take the medicine at evenly spaced intervals, such as every 12 hours if you take it two times a day, or every 8 hours if you take it three times a day.

  • Your doctor will tell you how much medicine to use. Do not use more than directed.

What to do if you miss a dose of Propylthiouracil

  • Take a dose as soon as you remember. If it is almost time for your next dose, wait until then and take a regular dose. Do not take extra medicine to make up for a missed dose.

  • Oral routeAsk your pharmacist, doctor, or health caregiver about the best way to dispose of any outdated medicine or medicine no longer needed.

  • Keep all medicine out of the reach of children. Never share your medicine with anyone.

Propylthiouracil contraindications

  • You should not use this medicine if you have had an allergic reaction to propylthiouracil, or if you are pregnant or breastfeeding.

Propylthiouracil warnings

  • Your doctor will check your progress and the effects of this medicine at regular visits. Keep all appointments. Blood tests may be needed to check for unwanted effects.

  • Severe fever or chills, or fever that lasts longer than 2 days.

  • Skin rash or itching.

  • Swelling in your neck (thyroid).

  • Unexplained bleeding or bruising.

  • Unusual weakness.

  • Yellowing of your skin or the whites of your eyes.

  • It is not safe to take this medicine during pregnancy. It could harm an unborn baby. Tell your doctor right away if you become pregnant.

  • Make sure your doctor knows if you have liver disease.

  • It may take several days or weeks for propylthiouracil to start working. Do not stop using the medicine without talking to your doctor.

  • This medicine may make you bleed, bruise, or get infections more easily. Take precautions to prevent illness and injury. Wash your hands often.

  • Liver problems may occur with this medicine. Stop using this medicine and check with your doctor right away if you are having more than one of these symptoms: right upper abdominal or stomach pain or tenderness; clay-colored stools; dark urine; decreased appetite; fever; headache; itching; loss of appetite; nausea and vomiting; skin rash; swelling of the feet or lower legs; unusual tiredness or weakness; or yellow eyes or skin.

  • Tell any doctor or dentist who treats you that you are using this medicine. You may need to stop using this medicine several days before you have surgery or medical tests.

Propylthiouracil interactions

  • Talk to your doctor before getting any vaccines (such as flu shots). Also, other people living in your home should not get oral polio vaccine while you are using this medicine. There is a chance they could pass on the polio virus to you.

  • It may take several days or weeks for propylthiouracil to start working. Do not stop using the medicine without talking to your doctor.

  • This medicine may make you bleed, bruise, or get infections more easily. Take precautions to prevent illness and injury. Wash your hands often.

  • Liver problems may occur with this medicine. Stop using this medicine and check with your doctor right away if you are having more than one of these symptoms: right upper abdominal or stomach pain or tenderness; clay-colored stools; dark urine; decreased appetite; fever; headache; itching; loss of appetite; nausea and vomiting; skin rash; swelling of the feet or lower legs; unusual tiredness or weakness; or yellow eyes or skin.

  • Tell any doctor or dentist who treats you that you are using this medicine. You may need to stop using this medicine several days before you have surgery or medical tests.

  • Your doctor will check your progress and the effects of this medicine at regular visits. Keep all appointments. Blood tests may be needed to check for unwanted effects.

  • Make sure your doctor knows if you are also using amiodarone (Cordarone®), certain blood pressure medicine (such as atenolol, metoprolol, propranolol, Inderal®, or Toprol®), potassium supplements, a blood thinner (such as warfarin, Coumadin®), theophylline (Theo-Dur®), or digoxin (Lanoxin®).

Propylthiouracil side effects

Serious Side Effects

  • Dry, puffy skin.

  • Unexplained bleeding or bruising.

  • Severe fever or chills, or fever that lasts longer than 2 days.

  • Allergic reaction: Itching or hives, swelling in your face or hands, swelling or tingling in your mouth or throat, chest tightness, trouble breathing

  • Swelling in your neck (thyroid).

  • Dark-colored urine or pale stools.

  • Nausea, vomiting, loss of appetite, or pain in your upper stomach.

  • Yellowing of your skin or the whites of your eyes.

  • Cough or sore throat.

  • Mouth sores.

  • Unusual weakness.

  • Changes in menstrual periods.

  • Skin rash or itching.

Less Serious Side Effects

  • Headache.