Dexamethasone

Indications

Dexamethasone is used for: Shock, Bronchial asthma, Status asthmaticus, Rheumatoid arthritis, Gout, Severe allergies, Skin diseases, Hyperpyrexia, Bacteraemia, Toxaemia, Acute adrenocortical insufficiency, Cortisosteroid-responsive dermatoses, Eczema, Urticaria, Cerebral oedema, COVID-19 Disease (Off-label), other indications where glucocorticoid therapy is required.

Adult Dose

Oral Anti-inflammatory Adult: 0.75-9 mg daily in 2-4 divided doses; Screening test for Cushing's syndrome Adult: 0.5 mg every 6 hr for 48 hr after determining baseline 24-hr urinary 17-hydroxycorticosteroid (17-OHCS) concentrations. During the second 24 hr of dexamethasone admin, urine is collected and analysed for 17-OHCS. Alternatively, after a baseline plasma cortisol determination, 1 mg may be given at 11 pm and plasma cortisol determined at 8 am the next morning. Plasma cortisol and urinary output of 17-OHCS are depressed after dexamethasone admin in normal individuals but remain at basal levels in patients with Cushing's syndrome. Acute exacerbations in multiple sclerosis Adult: 30 mg daily for 1 wk followed by 4-12 mg daily for 1 mth. COVID-19 Disease (Off-label) Based on preliminary evidenced from the RECOVERY trial, NIH guidelines recommends dexamethasone to reduce mortality in hospitalized patients with COVID-19 disease who are receiving either invasive mechanical ventilation or oxygen alone, but not among those receiving no respiratory support 6 mg PO/IV qDay for up to 10 days or discharge, whichever comes first

Child Dose

Oral Anti-inflammatory Child: 1 mth-18 yr: 10-100 mcg/kg daily in 1-2 divided doses via oral admin, adjusted according to response; up to 300 micrograms/kg daily may be used in emergency situations. Acute exacerbations in multiple sclerosis Child: 1 mth-12 yr: 100-400 mcg/kg daily in 1-2 divided doses; 12-18 yr: Initially 0.5-24 mg daily. Max. 24 mg daily.

Renal Dose

Administration

Should be taken with food.

Contra Indications

Ocular herpes simplex is an example of absolute contraindication to corticosteroid therapy. Relative contraindications are: Gastrointestinal ulcer, acute or chronic infections, osteoporosis, pregnancy, diabetes mellitus, renal insufficiency, hypertension, history of psychotic illness, immediate before prophylactic immunization and finally hypersensitivity to Dexamethasone.

Precautions

Dexamethasone should be used with caution in the presence of congestive heart failure or hypertension, in patients with diabetes mellitus, epilepsy, glaucoma, infectious disease, chronic renal failure and uraemia and in elderly persons. Lactation: Drug excreted in breast milk; not recommended

Pregnancy-Lactation

Pregnancy Corticosteroids readily cross the placenta Adverse developmental outcomes including orofacial clefts (cleft lip with or without cleft palate), intrauterine growth restriction, and decreased birth weight have been reported with maternal use of corticosteroids during pregnancy Pregnancy testing is recommended for females of reproductive potential before initiating treatment Contraception Use effective contraception during treatment and for at least 1 month following final dose Infertility in males Steroids may increase or decrease motility and number of spermatozoa in some patients In animals, dexamethasone affects male spermatogenesis Lactation Systemically administered corticosteroids appear in human milk and could suppress growth, interfere with endogenous corticosteroid production, or cause other untoward effects Advise women not to breastfeed during treatment and for 2 weeks after the last dose

Interactions

Increased risk of hypokalaemia when used concurrently with potassium-depleting drugs such as amphotericin B and loop diuretics. Reduces efficacy of isoniazid, salicylates, vaccines and toxoids. Increased activity of dexamethasone and cyclosporin when used together. Concurrent use with aspirin or ethanol may lead to increased GI side effects. Potentially Fatal: Reduced efficacy in combination with ephedrine, cholestyramine, phenytoin, phenobarbital and rifampicin.

Side Effects

Side effects of Dexamethasone : Acne, Adrenal suppression, Arrhythmia, Bradycardia, Cardiac arrest, Cataracts, Change in spermatogenesis, Delayed wound healing, Depression, Diabetes mellitus, Diaphoresis, Emotional instability, Erythema, Euphoria, Exophthalmos, GI perforation, Glaucoma, Glucose intolerance, Glucosuria, Hepatomegaly, Hypokalemic alkalosis, Increased intracranial pressure, Increased transaminases, Insomnia, Kaposi's sarcoma, Menstrual irregularity, Moon face, Myopathy, Neuritis, Osteoporosis, Peptic ulcer, Perianal pruritus, Petechia, Perianal pruritus, Pituitary adrenal axis suppression, Pseudotumor cerebri (on withdrawal), Psychosis, Pulmonary edema, Rash, Seizure, Spermatogenesis altered (increased or decreased), Ulcerative esophagitis, Urticaria, Vertigo, Weight gain

Mode of Action

Dexamethasone is a synthetic glucocorticoid which decreases inflammation by inhibiting the migration of leukocytes and reversal of increased capillary permeability. It suppresses normal immune response.