Dexamethasone

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. Dexamethasone inhibits phospholipase A2, the first step in prostaglandin synthesis, and inhibits chemotactic infiltration of neutrophils into the site of inflammation.

• Allergic states (asthma, atopic dermatitis, contact dermatitis, drug hypersensitivity)
• Collagen disease (lupus erythematosus, rheumatoid arthritis)
• Dermatologic diseases (pemphigus, Stevens-Johnson syndrome)
• Endocrine disorders (adrenocortical insufficiency, congenital adrenal hyperplasia)
• Gastrointestinal diseases (ulcerative colitis, Crohn's disease)
• Hematologic disorders (autoimmune hemolytic anemia, ITP)
• Neoplastic diseases (leukemias, lymphomas)
• Nervous system (multiple sclerosis, cerebral edema)
• Ophthalmic diseases (uveitis, temporal arteritis)
• Renal diseases (nephrotic syndrome)
• Respiratory diseases (sarcoidosis, tuberculosis)
• Rheumatic disorders (gout, ankylosing spondylitis)

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.

Dexamethasone inhibits phospholipase A2, reducing prostaglandin synthesis, and suppresses immune cell activity, thereby reducing inflammation and allergic reactions.

Adult (Oral): 0.75-9 mg daily in 2-4 divided doses; Multiple sclerosis: 30 mg daily for 1 week, then 4-12 mg daily for 1 month; Cushing's screening: 0.5 mg every 6 hours for 48 hours.
Child: 10-100 mcg/kg daily in 1-2 divided doses; up to 300 mcg/kg/day in emergencies.
Injection: 0.05-0.20 mg/kg/day; emergencies: 10-20 mg IV, then 6 mg every 6 hours.

Take with food (to avoid stomach upset). Swallow the tablet whole, do not chew, crush or break. Injection can be given IV, IM or locally.

If you miss a dose of Dexamethasone, take it as soon as possible. However, if it is almost time for your next dose, skip the missed dose. Do not double the dose.

Common: Mood changes, bone density reduction, stomach upset, Cushing syndrome, weight gain, acne.
Long-term: Osteoporosis, glaucoma, cataracts, muscle weakness, immunosuppression, hypertension, diabetes.

May affect driving ability (dizziness, vision changes, muscle weakness). Increased infection risk. Do not stop abruptly (gradual tapering required). Avoid live vaccines. Caution in diabetes, hypertension, osteoporosis, peptic ulcer, glaucoma, liver and kidney disease.

Absolute: Ocular herpes simplex.
Relative: GI ulcer, acute or chronic infections, osteoporosis, pregnancy, diabetes, renal insufficiency, hypertension, history of psychotic illness, hypersensitivity.

Potassium-depleting drugs (amphotericin B, loop diuretics): Increased risk of hypokalemia.
Isoniazid, salicylates, vaccines: Reduced efficacy.
Cyclosporin: Increased activity.
Aspirin, ethanol: Increased GI side effects.
Ephedrine, cholestyramine, phenytoin, phenobarbital, rifampicin: Reduced efficacy.

It is unsafe to consume alcohol with Dexamethasone (increases GI side effects).

Pregnancy Category C. Dexamethasone may be unsafe during pregnancy. Animal studies have shown harmful effects. Prolonged or repeated use may increase risk of intrauterine growth retardation.

Dexamethasone is excreted in breast milk. Mothers taking high dosages should be advised not to breastfeed.

Pediatric patients should be titrated to the lowest effective dose to minimize growth effects.

Elderly patients should be used with caution (higher risk of osteoporosis, diabetes, hypertension).

Renal impairment: Probably safe in kidney disease. No dose adjustment may be needed. Regular kidney function monitoring is advisable.
Hepatic impairment: Use with caution. Dose adjustment may be needed.

Treatment of overdose is by supportive and symptomatic therapy.

Tablet: Store in a cool & dry place, protected from light & moisture.
Injection: Store below 30°C, protected from light. Do not freeze.

Dexamethasone