DOSAGE AND ADMINISTRATION For Oral Administration The initial dosage varies from 0.75 to 9 mg a day depending on the disease being treated. It Should Be Emphasized That Dosage Requirements Are Variable And Must Be Individualized On The Basis Of The Disease Under Treatment And The Response Of The Patient. After a favorable response is noted, the proper maintenance dosage should be determined by decreasing the initial drug dosage in small decrements at appropriate time intervals until the lowest dosage that maintains an adequate clinical response is reached. Situations which may make dosage adjustments necessary are changes in clinical status secondary to remissions or exacerbations in the disease process, the patient's individual drug responsiveness, and the effect of patient exposure to stressful situations not directly related to the disease entity under treatment. In this latter situation it may be necessary to increase the dosage of the corticosteroid for a period of time consistent with the patient's condition. If after long-term therapy the drug is to be stopped, it is recommended that it be withdrawn gradually rather than abruptly. In the treatment of acute exacerbations of multiple sclerosis, daily doses of 30 mg of dexamethasone for a week followed by 4 to 12 mg every other day for one month have been shown to be effective (see PRECAUTIONS: Neuro-Psychiatric ). In pediatric patients, the initial dose of dexamethasone may vary depending on the specific disease entity being treated. The range of initial doses is 0.02 to 0.3 mg/kg/day in three or four divided doses (0.6 to 9 mg/m2bsa/day). For the purpose of comparison, the following is the equivalent milligram dosage of the various corticosteroids: Dexamethasone, 1.5 Methylprednisolone, 8 Prednisone, 10 Triamcinolone, 8 Prednisolone, 10 Betamethasone, 1.5 Hydrocortisone, 40 Paramethasone, 4 Cortisone, 50 These dose relationships apply only to oral or intravenous administration of these compounds. When these substances or their derivatives are injected intramuscularly or into joint spaces, their relative properties may be greatly altered. In acute, self-limited allergic disorders or acute exacerbations of chronic allergic disorders, the following dosage schedule combining parenteral and oral therapy is suggested: Dexamethasone sodium phosphate injection, 4 mg per mL First Day 1 or 2 mL, intramuscularly Dexamethasone tablets, 0.75 mg Second Day 4 tablets in two divided doses Third Day 4 tablets in two divided doses Fourth Day 2 tablets in two divided doses Fifth Day 1 tablet Sixth Day 1 tablet Seventh Day No treatment Eighth Day Follow-up visit This schedule is designed to ensure adequate therapy during acute episodes, while minimizing the risk of overdosage in chronic cases. In cerebral edema , dexamethasone sodium phosphate injection is generally administered initially in a dosage of 10 mg intravenously followed by 4 mg every six hours intramuscularly until the symptoms of cerebral edema subside. Response is usually noted within 12 to 24 hours and dosage may be reduced after two to four days and gradually discontinued over a period of five to seven days. For palliative management of patients with recurrent or inoperable brain tumors, maintenance therapy with either dexamethasone sodium phosphate injection or dexamethasone tablets in a dosage of 2 mg two or three times daily may be effective. Dexamethasone Suppression Tests 1. Tests for Cushing’s syndrome Give 1.0 mg of dexamethasone orally at 11:00 p.m. Blood is drawn for plasma cortisol determination at 8:00 a.m. the following morning. For greater accuracy, give 0.5 mg of dexamethasone orally every 6 hours for 48 hours. Twenty-four hour urine collections are made for determination of 17-hydroxycorticosteroid excretion. 2. Test to distinguish Cushing’s syndrome due to pituitary ACTH excess from Cushing’s syndrome due to other causes. Give 2.0 mg of dexamethasone orally every 6 hours for 48 hours. Twenty-four hour urine collections are made for determination of 17-hydroxycorticosteroid excretion.