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.
Patients can eat and drink normally and take all their usual medications prior to the test. Estrogen containing medications, including the contraceptive pill and hormone replacement therapy, should be stopped for six weeks prior to measuring serum cortisol. This is because estrogen induces cortisol binding globulin and leads to elevations in measured serum cortisol. Any steroid containing medications should also be documented, and avoided if possible, as they may interfere with the hypothalamo-pituitary-adrenal axis, or cross react with the cortisol assay.