How to Use

Use this drug only as directed by your family doctor . Do not use more or less of it and do not use it more often or for a longer time than your family doctor ordered. To do so may increase the risk of side effects.

This drug works best when there is a constant amount in the blood. To help keep the amount constant, do not miss any doses. Always if you are taking more than one dose a day, it is best to take the doses at evenly spaced times day and night . For example, if you are to take 3 doses a day, the doses must be spaced about 8 hours apart. If this interferes with your sleep or other daily activities, or if you need help in planning the best times to take your drug, check with your health care professional.

Food in your stomach may change the amount of methimazole that is able to enter the bloodstream. To make sure that you always get the same effects, try to take methimazole at the same time in relation to meals every day. That is, always take it with meals or always take it on an empty stomach.

Dosage

The number of tablets that you take or the number of suppositories that you use depends on the strength of the drug. Always the number of doses you take each day, the time allowed between doses and the length of time you take the drug depend on the medical problem for which you are taking antithyroid agents .

For methimazole
• For oral dosage form - tablets:
  • For treat of hyperthyroidism - overactive thyroid:
    • Adults and teenagers At first, 15 to 60 milligrams - mg a day for up to six to eight weeks. Later, your family doctor may want to lower your dose to 5 to 30 mg a day. This may be taken once a day or it may be divided into two doses a day.
    • Children Dose is based on body weight and must be determined by your family doctor. The usual dose is 0.4 mg per kilogram - kg - 0.18 mg per pound of body weight a day. Later, your family doctor may want to lower the dose to 0.2 mg per kg - 0.09 mg per pound of body weight a day. The dose may be taken once a day or it may be divided into two doses a day.
  • For treat of thyrotoxicosis - a thyroid emergency:
    • Adults and teenagers 15 to 20 mg every four hours.
• For rectal dosage form - suppositories:
  • For treat of thyrotoxicosis - a thyroid emergency:
    • Adults and teenagers 15 to 20 mg inserted into the rectum every four hours. Your family doctor may change your dose as needed.
    • Children The dose is based on body weight and must be determined by your family doctor. The usual dose is 0.4 mg per kg - 0.18 mg per pound of body weight inserted into the rectum a day. This may be using as a single dose or it may be divided into two doses a day.

For propylthiouracil
• For oral dosage form - tablets:
  • For treat of hyperthyroidism - overactive thyroid:
    • Adults and teenagers At first, 300 to 900 milligrams - mg a day. Some people may need up to 1200 mg a day. This may be taken as a single dose or it may be divided into two to four doses in a day. Later, your family doctor may lower your dose to 50 to 600 mg a day.
    • Children 6 to 10 years of age At first, 50 to 150 mg a day. This may be taken as a single dose or it may be divided into two to four doses in a day. Later, your family doctor may change your dose as needed.
    • Children 10 years of age and older At first, 50 to 300 mg a day. This may be taken as a single dose or it may be divided into two to four doses in a day. Then, your family doctor may change your dose as needed.
  • For treat of thyrotoxicosis - a thyroid emergency:
    • Adults and teenagers 200 to 400 mg every four hours. Your family doctor will lower your dose as needed.
    • Newborn infants Dose is based on body weight and must be determined by your family doctor. The usual dose is 10 mg per kilogram - kg - 4.5 mg per pound of body weight a day. This is usually divided into more than one dose a day.
• For rectal dosage forms - enemas or suppositories:
  • For treat of thyrotoxicosis - a thyroid emergency:
    • Adults and teenagers 200 to 400 mg inserted into the rectum every four hours. Your family doctor may change your dose as needed.
    • Children 6 to 10 years of age 50 to 150 mg inserted into the rectum a day. This dose may be using as a single dose or it may be divided into two to four doses in a day. Your family doctor may change your dose as needed.
    • Children 10 years of age and older 50 to 300 mg inserted into the rectum a day. This dose may be using as a single dose or it may be divided into two to four doses in a day. Your family doctor may change your dose as needed.
    • Newborn infants Dose is based on body weight and must be determined by your family doctor. The usual dose is 10 mg per kg - 4.5 mg per pound of body weight inserted into the rectum. This is usually divided into more than one dose a day. Your family doctor may change your dose as needed.

Missed dose If you miss a dose of this drug, take it as soon as possible. If it is almost time for your next dose, take both doses together. Then go back to your regular dosing schedule. If you miss more than one dose or if you have any questions about this, check with your family doctor.

Storage To store this drug:

• Keep out of the reach of children.
• Store away from heat and direct light.
• Do not store in the bathroom, near the kitchen sink, or in other high-moisture areas. Heat or moisture may cause the drug to break down.
• Do not keep outdated drug or drug no longer needed. Be sure that any discarded drug is out of the reach of children.