Metirapone, with its unique pharmacological effects, has opened up a new path in the field of endocrine therapy.

1. Drug name

1. Common name: Metyrapone

2. Trade name: Metopirone®

II. Indications

This product is used in combination with other diagnostic tests to diagnose adrenal insufficiency in adult and pediatric patients.

III. Specifications and Characteristics

1. Specification: Soft capsule, each containing 250 mg of metyrapone.

2. Characteristics: White to yellowish-white, opaque, oblong capsules with the red "HRA" imprinted on one side.

IV. Main components

Active ingredient: Metyrapone.

5. Usage and Dosage

Single-dose short-course regimen (recommended usage):

1. Applicable population: Adult and pediatric patients.

2. Recommended dosage: Single dose at 30 mg/kg body weight (maximum dose not exceeding 3 grams).

3. Time of Administration: Take it at midnight, along with milk, yogurt, or Dim sum.

4. Blood sampling and testing: Collect blood samples the next morning (7:30-8:00) for the determination of plasma 11-deoxycorticosteroid and/or adrenocorticotropic hormone (ACTH) levels.

VI. Dose adjustment

This product is primarily intended for diagnostic testing, and the dosage is calculated based on body weight.

VII. Medication Precautions

1. Timing of medication (before or after meals): It is recommended to take it with a meal (milk, yogurt, or Dim sum) at midnight to improve tolerance.

2. Missed dose: This product is intended for a single diagnostic use and does not include instructions for missed or skipped doses. If the medication is not taken as scheduled, consult a doctor.

3. Vomiting: If vomiting occurs after taking the medication, it may affect drug absorption and the accuracy of test results. Patients should inform their doctors.

4. Important notice:

Before administering medication, it is necessary to confirm the responsiveness of the patient's adrenal glands through an exogenous ACTH stimulation test.

Before use, medications that may affect pituitary or adrenal cortex function (such as anticonvulsants, psychotropic drugs, hormone preparations, corticosteroids, antithyroid drugs, cyproheptadine, etc.) should be discontinued for at least 5 half-lives of the drug.

During and after the testing period, acute adrenal insufficiency may be induced. It is recommended that high-risk patients be hospitalized for observation, and prophylactic administration of glucocorticoids may be considered after blood sampling.

VIII. Medication for special populations

1. Children: It can be used to diagnose adrenal insufficiency in children, and the dosage is calculated based on body weight.

2. Elderly patients: Clinical research data is insufficient, but existing experience has not revealed any differences in response compared to younger adult patients.

3. Pregnant women: Metyrapone can pass through the placenta and may reduce fetal cortisol production. Unless there is a clear need, the benefits and risks should be carefully evaluated.

4. Lactating women: Metolazone and its active metabolite can be secreted in breast milk, and their effects on breastfed infants are unknown. The benefits of breastfeeding should be weighed against the necessity of maternal treatment.

5. Patients with hepatic insufficiency: Patients with cirrhosis may have a reduced response to metyrapone.

6. Patients with thyroid dysfunction: Hypothyroidism or hyperthyroidism may lead to a lower-than-normal response to the metyrapone test.

IX. Adverse reactions

1. Cardiovascular system: hypotension.

2. Digestive system: nausea, vomiting, abdominal discomfort or pain.

3. Central nervous system: headache, dizziness, sedation.

4. Skin: allergic rash.

5. Hematological system: leukopenia, anemia, and thrombocytopenia.

X. Contraindications

1. Hypersensitivity to metyrapone or any of its excipients is a contraindication.

2. Patients with adrenal insufficiency are prohibited from using this product.

XI. Drug interactions

1. The impact of other medications on metyrapone: Anticonvulsants, psychotropic drugs, hormone preparations, corticosteroids, antithyroid drugs, and cyproheptadine may affect the results of the metyrapone test. If it is not possible to discontinue these medications, the necessity of conducting the test needs to be reassessed.

2. Effects of metolazone on other drugs: This product inhibits the glucuronidation of acetaminophen, reducing its clearance rate and increasing the risk of adverse reactions. It should be avoided in combination with acetaminophen.

XII. Storage method

1. Store at room temperature between 20°C to 25°C (68°F to 77°F), with brief storage allowed between 15°C to 30°C (59°F to 86°F).

2. Keep the container sealed and avoid exposure to heat and moisture.

Metyraponeinformation