09/14, 2007
Uses of Antithyroid Agents Information
Type of Drug:
Antithyroid drugs.
How the Antithyroid Agents Works:
The oral antithyroid drugs inhibit the formation of thyroid hormones.
Uses of The Antithyroid Agents:
To treat hyperthyroidism (overactive thyroid gland). To treat or prepare the overactive thyroid for surgery or radioactive iodine therapy. Sodium iodide I 131 preparations may be used to treat certain forms of thyroid cancer.
Unlabeled Uses: Occasionally doctors may prescribe propylthiouracil to treat liver disease due to alcoholism.
Precatuions:
Pregnancy: Studies have shown a potential adverse effect to the fetus. Us only if clearly needed and the potential benefits to the mother outweigh the possible hazards to the fetus. These agents, if used carefully, are effective in treating hyperthyroidism complicated by pregnancy. Dose must be adequate but not excessive. These drugs cross the placenta and could induce goiter or even cretinism (congenital lack of thyroid secretion which can stop physical and mental development) in the fetus. Propylthiouracil is less likely than methimazole to cross the placenta.
Breastfeeding: Patients receiving antithyroid preparations should not breastfeed.
Children: Safety and effectiveness of sodium iodide I 131 in children have not been established. Sodium iodide I 131 is not usually used for treatment of hyperthyroidism in patients under 30 years of age unless circumstances preclude other methods of treatment.
Lab Tests: Lab tests will be required to monitor therapy. Tests include blood count , bone marrow function, and thyroid function.
Drug Interactions:
Tell your doctor or pharmacist if you are taking or planning to take any overÂthe-counter or prescription medications or dietary supplements while taking an antithyroid agent. Doses of one or both drugs may need to be modified or a different drug may need to be prescribed. The following drugs or drug classes interact with antithyroid agents:
Side Effects of Antithyroid Agents:
Every drug is capable of producing side effects. Many antithyroid agent users experience no, or minor, side effects. The frequency and severity of side effects depend on many factors including dose, duration of therapy, and individual susceptibility. Possible side effects include:
Digestive Tract: Nausea; vomiting; stomach upset or pain; loss of taste sensation; swelling of salivary glands.
Nervous System: Abnormal skin sensations; headache; drowsiness; depression; feeling of whirling motion; hyperactivity.
Skin: Unusual bleeding or bruising; rash; itching; hives; excessive skin pigmentation; yellowing of skin or eyes; abnormal hair loss.
Other: Joint or muscle pain; fever; fluid retention (edema); swollen lymph glands; abnormal blood counts; kidney disease; lung disease; liver disease; low blood sugar.
Other: Sodium iodide I 131 only: Radiation sickness (eg, nausea, vomiting); anemia; chromosomal abnormalities; tenderness and swelling of the neck; pain on swallowing; sore throat; cough; temporary thinning of hair.
Guidelines for Use:
- Dosage is individualized. Take exactly as prescribed.
- Do not change the dose or stop taking this medicine unless advised to do so by your doctor.
- Take methimazole or propylthiouracil at regular intervals around the clock (usually every 8 hours), unless directed otherwise by your doctor.
- Notify your doctor if fever, sore throat, hay fever, unusual bleeding or bruising, headache, general body discomfort, rash, yellowing of the skin, vomiting, itching, appetite loss, skin surface changes, or pain in the upper right side of your body occurs.
- If a dose of methimazole or propylthiouracil is missed, take it as soon as possible. If several hours have passed or it is nearing time for the next dose, do not double the dose to catch up, unless advised to do so by your doctor. If more than one dose is missed or it is necessary to establish a new dosage schedule, contact your doctor or pharmacist.
- Lab tests will be required to monitor therapy. Be sure to keep appointments.
- Store methimazole or propylthiouracil at room temperature (59° to 86°F). Store sodium iodide I 131 at room temperature controlled in compliance with government regulations.
Tagged under:antithyroid drugs, overactive thyroid gland, Thyroid Drugs, thyroid secretion treatment of hyperthyroidism