DEXAMETHASONE SODIUM PHOSPHATE INJECTION USP

INJECTION

**Dosage and administration** DEXAMETHASONE SODIUM PHOSPHATE INJECTION USP can be given without mixing or dilution. Use only clear and colourless solutions. Discard any unused solution after opening ampoule. Use the contents of the injection solution only once. _All dosage recommendations are given in units of dexamethasone phosphate._ _Intravenous and intramuscular injection:_ General considerations Dosage must be individualized on the basis of the disease and the response of the patient. In order to minimize side effects, the lowest possible dosage adequate to control the disease process should be used (see ‘Side Effects’ – _please refer to the Product Insert/Patient Information Leaflet published on HSA for the full drug information_). Usually the parenteral dosage ranges are one-third to one-half the oral dose, given every 12 hours. The usual initial dosage is 0.5 – 20 mg (0.125 – 5 mL) a day. In situations of less severity, lower doses will generally suffice. However, in certain overwhelming, acute, life-threatening situations, administration in dosages exceeding the usual dosages may be justified. In these circumstances, the slower rate of absorption by intramuscular administration should be recognised. The initial dosage should be maintained or adjusted until a satisfactory response is noted. Both the dose in the evening, which is useful in alleviating morning stiffness, and the divided dosage regimen are associated with greater suppression of the hypothalamo-pituitary-adrenal axis. After a favourable response is noted, the proper maintenance dosage should be determined by decreasing the initial dosage by small amounts at appropriate intervals to the lowest dosage which will maintain an adequate clinical response. Chronic dosage should preferably not exceed 500 micrograms dexamethasone daily. Close monitoring of drug dosage is needed. If DEXAMETHASONE SODIUM PHOSPHATE INJECTION USP is to be stopped after it has been given for more than a few days, it should be withdrawn gradually rather than stopped abruptly. Whenever possible, the intravenous route should be used for the initial dose and for as many subsequent doses as are given while the patient is in shock (because of the irregular rate of absorption of any medicament administered by any other route in such patients). When the blood pressure responds, use the intramuscular route until oral therapy can be substituted. For the comfort of the patient, not more than 2 ml should be injected intramuscularly at any one site. Emergencies treatment The usual dose of DEXAMETHASONE SODIUM PHOSPHATE INJECTION USP by intravenous or intramuscular injection is 4 – 20 mg (1 – 5 mL), depending on the severity of the condition (see also «Shock»). This dose may be repeated until adequate response is noted. After initial improvement, single doses of 2 – 4 mg (0.5 – 1 mL) repeated as necessary, should be sufficient. The total daily dosage usually need not exceed 80 mg (20 mL), even in severe conditions. When constant maximal effect is desired, dosage must be repeated at three-hour or four-hour intervals, or maintained by slow intravenous drip. Intravenous and intramuscular injections are advised in acute illness. When the acute stage has passed, oral steroid therapy should be substituted as soon as feasible. Shock (of haemorrhagic, traumatic or surgical) Usually 2 to 6 mg/kg body weight as a single intravenous injection. This may be repeated in two to six hours if shock persists. Alternatively, this may be followed immediately by the same dose in an intravenous infusion. Therapy with DEXAMETHASONE SODIUM PHOSPHATE INJECTION USP is an adjunct to, and not a replacement for conventional therapy. Administration of these high doses should be continued only until the patient’s condition has stabilised and usually no longer than 48 – 72 hours. Cerebral oedema Associated with primary or metastatic brain tumour, pre-operative preparation of patients with increased intracranial pressure secondary to brain tumour: initially 10 mg (2.5 mL) intravenously, followed by 4 mg (1 mL) intramuscularly every six hours until symptoms of cerebral oedema subside. Response is usually noted within 12 – 24 hours; dosage may be reduced after two to four days and gradually discontinued over five to seven days. High doses of DEXAMETHASONE SODIUM PHOSPHATE INJECTION USP are recommended for initiating short-term intensive therapy for acute life-threatening cerebral oedema. Following the high loading dose schedule of the first day of therapy, the dose is scaled down over the seven to ten day period of intensive therapy and subsequently reduced to zero over the next seven to ten days. When maintenance therapy is required, substitute oral Dexamethasone as soon as possible (see table below). Palliative management of recurrent or inoperable brain tumours: Maintenance therapy should be determined for each patient: 2 mg (0.5 mL) two or three times a day may be effective. The smallest dosage necessary to control cerebral oedema should be used. Suggested high dose schedule in cerebral oedema: Adults: Initial Dose50 mg IV1st day8 mg IV every 2 hours2nd day8 mg IV every 2 hours3rd day8 mg IV every 2 hours4th day4 mg IV every 2 hours5th day – 8th day4 mg IV every 4 hoursThereafterdecrease by daily reduction of 4 mg Children (35 kg and over): Initial Dose25 mg IV1st day4 mg IV every 2 hours2nd day4 mg IV every 2 hours3rd day4 mg IV every 2 hours4th day4 mg IV every 4 hours5th day – 8th day4 mg IV every 6 hoursThereafterdecrease by daily reduction of 2 mg Children (below 35 kg): Initial Dose20 mg IV1st day4 mg IV every 3 hours2nd day4 mg IV every 3 hours3rd day4 mg IV every 3 hours4th day4 mg IV every 6 hours5th day – 8th day2 mg IV every 6 hoursThereafterdecrease by daily reduction of 1 mg Intrasynovial, intralesional, and soft-tissue injection In general, these injections are employed when only one or two joints or areas are affected. Some of the usual single doses are:  Frequency of injection: once every three to five days to once every two to three weeks, depending on response. Use in children Dosage should be limited to a single dose on alternate days to minimise suppression of the hypothalamo-pituitary-adrenal axis. Use in the elderly Treatment of elderly patients, particularly if long term, should be planned bearing in mind the more serious consequences of the common side effects of corticosteroids in old age, especially osteoporosis, diabetes, hypertension, susceptibility to infection and thinning of the skin. Close clinical supervision is required to avoid life threatening reactions (see ‘Side-effects’ – _please refer to the Product Insert/Patient Information Leaflet published on HSA for the full drug information_).