Notice: Images are for illustration only and may not reflect the exact product you receive. Brand-name medications may look different depending on their country of origin—Canadian versions, for example, often include a "PR" symbol on the packaging. Rest assured, the medication, dosage, and active ingredients will be exactly as prescribed. Canada Pharmacy Store is committed to your health and safety, and we work only with licensed pharmacies to ensure you receive trusted, high-quality medication every time.
General Medication Fact Sheet for Propylthiouracil
| Field | Information |
|---|---|
| Generic Name | Propylthiouracil |
| Brand Name Versions | None (Generic Only) |
| Boxed/Label Warning | Propylthiouracil can cause severe liver injury and acute liver failure, in some cases leading to death or liver transplant. It is also associated with an increased risk of birth defects. |
| Purpose | Antithyroid agent used to treat hyperthyroidism (overactive thyroid) |
| Mechanism of Action | Inhibits the production of thyroid hormones by blocking the enzyme thyroid peroxidase and preventing the conversion of T4 to T3 in peripheral tissues. |
| Dosage Forms | Oral tablets |
| Available Strengths | 50 mg |
| Dosage Frequency | Typically three times daily, or as directed by a healthcare provider |
| Common Side Effects | Nausea, vomiting, headache, rash, itching, joint pain |
| Serious Side Effects | Liver damage, agranulocytosis (low white blood cell count), vasculitis, severe allergic reactions |
| Drug Interactions | Anticoagulants (e.g., warfarin), digoxin, theophylline |
| Important Notes | Report signs of liver problems (e.g., jaundice, dark urine) or infection (e.g., fever, sore throat) immediately to your doctor; regular blood tests are required. This medication can cause harm to a developing baby and is only recommended when other options are not appropriate. |
| Storage | Store at room temperature away from moisture and light |
| Missed Dose | Take as soon as you remember; if it is almost time for your next dose, skip the missed dose and continue with your regular dosing schedule. Do not double the dose. |
| Alternatives | Methimazole, Radioactive Iodine, Thyroidectomy |
Propylthiouracil Alternatives
| Medication | Mechanism of Action | Notes |
|---|---|---|
| Methimazole (Tapazole) | Inhibits thyroid hormone synthesis. | Generally preferred over propylthiouracil due to a lower risk of liver damage. |
| Radioactive Iodine | Destroys thyroid cells. | Administered orally; often leads to hypothyroidism. |
| Thyroidectomy | Surgical removal of the thyroid gland. | Reserved for certain cases (e.g., large goiters, pregnancy contraindications). |
Propylthiouracil Side Effects
| Common Side Effects | Serious Side Effects |
|---|---|
| Nausea | Liver damage |
| Vomiting | Agranulocytosis (low white blood cell count) |
| Headache | Vasculitis |
| Rash | Severe allergic reactions (hives, swelling, difficulty breathing) |
| Itching | Hypothyroidism (underactive thyroid) |
| Joint pain | Lupus-like syndrome |
Propylthiouracil Dosage Guide
| Condition | Starting Dose | Maintenance Dose | Administration Notes |
|---|---|---|---|
| Hyperthyroidism | 300-600 mg daily | 100-150 mg daily | Divided into three doses; adjust based on thyroid function tests. |
