Professional Information

Dexamethasone

Pronunciation: (DEX-a-METH-a-sone)
Class: Glucocorticoid, Corticosteroid

Trade Names:
Decadron
- Tablets 0.5 mg
- Tablets 0.75 mg

Trade Names:
Decaspray
- Aerosol 0.04%

Trade Names:
Dexamethasone
- Tablets 0.5 mg
- Tablets 0.75 mg
- Tablets 1 mg
- Tablets 1.5 mg
- Tablets 2 mg
- Tablets 4 mg
- Tablets 6 mg
- Elixir 0.5 mg per 5 mL
- Solution, oral 0.5 mg per 5 mL

Trade Names:
Dexamethasone Intensol
- Concentrate, oral 1 mg/mL

Trade Names:
Dexpak 6 Day Taper Pak
- Tablets (21 tablets) 1.5 mg

Trade Names:
Dexpak 10 Day Taper Pak
- Tablets (35 tablets) 1.5 mg

Trade Names:
Dexpak 13 Day Taper Pak
- Tablets (51 tablets) 1.5 mg

Trade Names:
Maxidex
- Suspension, ophthalmic 0.1%

Apo-Dexamethasone (Canada)
ratio-Dexamethasone (Canada)
Dexamethasone Sodium Phosphate

Trade Names:
Decadron Phosphate
- Cream 0.1%

Trade Names:
Dexamethasone Sodium Phosphate
- Injection 4 mg/mL
- Injection 10 mg/mL
- Solution, ophthalmic 0.1%
- Solution, otic 0.1%

Trade Names:
Dexasol
- Solution, ophthalmic 0.1%

Trade Names:
Hexadrol Phosphate
- Injection 20 mg/mL

PMS-Dexamethasone (Canada)

Pharmacology

Synthetic long-acting glucocorticoid that depresses formation, release, and activity of endogenous mediators of inflammation, including prostaglandins, kinins, histamine, liposomal enzymes, and complement expression. Also modifies the body's immune response.

Pharmacokinetics

Metabolism

Metabolized in the liver by CYP3A4.

Elimination

The t _½ 1.8 to 3.5 h.

Onset

Rapid (injection).

Duration

Short (injection).

Indications and Usage

Testing of adrenal cortical hyperfunction; management of allergic and inflammatory ophthalmic processes, allergic states, cerebral edema associated with primary or metastatic brain tumor, collagen diseases, craniotomy or head injury, dermatologic diseases, edematous states (caused by nephrotic syndrome), GI diseases, hematologic disorders, multiple sclerosis, neoplastic diseases, primary or secondary adrenal cortex insufficiency, respiratory diseases, rheumatic disorders, trichinosis with neurologic or myocardial involvement, tuberculous meningitis.

Intralesional administration

Treatment for conditions such as alopecia areata, discoid lupus erythematosus, keloids, and psoriatic plaques.

Intra-articular or soft-tissue administration

Short-term adjunctive treatment for conditions such as synovitis of osteoarthritis, rheumatoid arthritis, acute gouty arthritis, and posttraumatic osteoarthritis.

Ophthalmic

Treatment of steroid-responsive inflammatory conditions of palpebral and bulbar conjunctiva, lid, cornea, and anterior segment of globe; sympathetic ophthalmia; temporal arteritis; uveitis.

Otic (using ophthalmic solution)

Steroid-responsive inflammatory conditions of the external auditory meatus, such as allergic otitis externa.

Unlabeled Uses

Treatment of nonrheumatic carditis; mixed connective tissue disease; polyarteritis nodosa; relapsing polychondritis; vasculitis; diagnosis of endogenous depression; severe eczema; pemphigoid; localized cutaneous sarcoid; sarcoidosis; hemolysis; prevention of nausea and vomiting associated with chemotherapy, especially cisplatin-containing regimens; breast and prostatic carcinoma; adjunct treatment for fever caused by malignant neoplasm; adjunct treatment for brain neoplasm; multiple myeloma; myasthenia gravis; cerebral ischemia; cerebri pseudomotor; desquamative gingivitis; oral lesions associated with corticosteroid responsive disorder; recurrent aphthous stomatitis; pericarditis; nasal polyps; croup; acute and chronic asthmatic bronchitis; noncardiogenic pulmonary edema; airway-obstructing hemangioma in infants; respiratory distress syndrome; acute calcium pyrophosphate deposition disease; Reiter disease; rheumatic fever; organ transplant rejection; prophylaxis for acute mountain sickness; adjunctive treatment for bacterial meningitis.

Contraindications

Systemic fungal infections; IM use in idiopathic thrombocytopenic purpura; coadministration with live virus vaccines; topical monotherapy in primary bacterial infections; intranasal use in untreated localized infections involving nasal mucosa; ophthalmic use in acute superficial herpes simplex keratitis, fungal diseases of ocular structures, vaccinia, varicella, and ocular tuberculosis.

Dosage and Administration

All dosages shown are for adults unless indicated otherwise.

Acute Allergic Disorders

IM / PO

First day

IM 4 or 8 mg.

Second and Third days

PO 1.5 mg twice daily.

Fourth day

PO 0.75 mg twice daily.

Fifth and Sixth days

PO 0.75 mg daily.

Seventh day

No treatment.

Eighth day

Follow-up visit.

Steroid Responsive Inflammatory Ophthalmic Conditions
Adults

Ophthalmic

Ophthalmic suspension

Instill 1 or 2 drops in conjunctival sac. In mild disease, drops may be used up to 4 to 6 times daily. In severe disease, drops may be used hourly, being tapered to discontinuation as inflammation subsides.

Ophthalmic solution

Instill 1 or 2 drops into conjunctival sac every hour during the day and every 2 h during the night. When a favorable response is observed, reduce dose to 1 drop every 4 h. Then, 1 drop 3 to 4 times daily may be sufficient.

Steroid-Responsive Inflammatory Otic Conditions
Adults

Otic Instill ophthalmic solution 3 or 4 drops directly into the aural canal 2 or 3 times daily. When favorable response is obtained, gradually reduce dose and eventually discontinue.

Dexamethasone
Initial dose

PO 0.75 to 9 mg/day.

Suppression tests Cushing syndrome

PO 1 mg at 11 pm or 0.5 mg every 6 h for 48 h.

To distinguish pituitary adrenocorticotropic hormone (ACTH) excess caused by Cushing syndrome from other causes

PO 2 mg every 6 h for 48 h.

Dexamethasone Sodium Phosphate
Systemic

IV / IM 0.5 to 9 mg/day.

Brain tumors

IV / IM 2 mg 2 to 3 times daily.

Cerebral edema

IV 10 mg, then 4 mg IM every 6 h until max response.

Intra-articular, intralesional, or soft tissue

Large joints, 2 to 4 mg; small joints, 0.8 to 1 mg; bursae, 2 to 3 mg; tendon sheaths, 0.4 to 1 mg; soft tissue infiltration, 2 to 6 mg; ganglia 1 to 2 mg.

Unresponsive shock

IV 1 to 6 mg/kg as single injection or 40 mg followed by repeated IV injections every 2 to 6 h.

Ophthalmic solution

Instill 1 to 2 drops into conjunctival sac every 1 h during day and every 2 h during night.

Ophthalmic solution (for use in ears)

Instill 3 or 4 drops into ear canal 2 to 3 times per day.

General Advice

Withdraw treatment gradually after long-term therapy.
Ophthalmic suspension: Shake well before using.

Storage/Stability

Refer to package insert for directions on how to store each particular form of dexamethasone.

Tablets

Store at 68° to 77°F. Protect from moisture and light.

Elixir

Store at 59° to 86°F. Avoid freezing.

Oral solution

Store at 68° to 77°F. Do not freeze. Protect from light.

Ophthalmic solution

Store at 59° to 86°F.

Ophthalmic suspension

Store upright at 46° to 80°F.

Injection

Store at 68° to 77°F. Protect from light and freezing.

Drug Interactions

Aminoglutethimide

May decrease dexamethasone-induced adrenal suppression.

Amphotericin B

Cardiac enlargement and CHF have been reported.

Anticholinesterases

May antagonize anticholinesterase effects in myasthenia gravis.

Anticoagulants, oral

May alter anticoagulant dose requirements.

Antidiabetic agents

Dexamethasone may increase blood glucose levels, necessitating antidiabetic agent dosage adjustments.

Aprepitant

Dexamethasone plasma levels may be elevated and the t _½ prolonged, increasing the pharmacologic effects and adverse reactions.

Cholestyramine, epinephrine

Dexamethasone plasma levels may be reduced, decreasing the efficacy.

Cyclosporine

Activity of both cyclosporine and dexamethasone may be increased. In addition, convulsions have been reported.

CYP3A4 substrates (eg, erythromycin, indinavir)

Plasma levels may be reduced by dexamethasone, decreasing efficacy.

Digoxin

Because of possible dexamethasone-induced hypokalemia, the risk of arrhythmias may be increased.

Hepatic enzyme inducers (eg, barbiturates, carbamazepine, phenytoin, rifampin)

Dexamethasone plasma levels may be reduced, decreasing the efficacy. In addition, seizure control with phenytoin may be altered.

Hepatic enzyme inhibitors (eg, azole antifungal agents [eg, ketoconazole], estrogens [including oral contraceptives], macrolide antibiotics [eg, erythromycin])

Dexamethasone plasma levels may be elevated, increasing the pharmacologic effects and adverse reactions. In addition, ketoconazole can inhibit adrenal corticosteroid synthesis, causing adrenal insufficiency during dexamethasone withdrawal.

NSAIDs, salicylates

Risk of GI adverse reactions may be increased. In addition, salicylate levels and efficacy may be reduced.

Potassium-depleting agents (eg, amphotericin B, loop and thiazide diuretics)

Risk of hypokalemia may be increased.

Thalidomide

Use with caution, toxic epidermal necrolysis has been reported with concurrent use of dexamethasone.

Laboratory Test Interactions

May cause increased urine glucose and serum cholesterol; decreased serum levels of potassium, T ₃ , and T ₄ ; decreased uptake of thyroid 131 iodine; false-negative nitroblue-tetrazolium test; altered brain scan results; suppression of skin test reactions. False-negative results to the dexamethasone suppression test may occur in patients receiving indomethacin.

Adverse Reactions

Cardiovascular

Arrhythmias, bradycardia, cardiac arrest, cardiac enlargement, CHF, circulatory collapse, fat embolism, hypertension, hypertrophic cardiomyopathy in premature infants, myocardial rupture following recent MI, pulmonary edema, syncope, tachycardia, thromboembolism, vasculitis.

CNS

Convulsions, emotional instability, euphoria, headache, increased appetite, increased intracranial pressure with papilledema (pseudotumor cerebri) usually following discontinuation of treatment, insomnia, malaise, mood swings, neuritis, neuropathy, paresthesia, personality changes, psychic disorders, vertigo.

Dermatologic

Acne; allergic dermatitis; dry scaly skin; ecchymosis and petechiae; erythema; impaired wound healing; increased sweating; rash; striae; suppression of skin test reactions; thin, fragile skin; thinning scalp hair; urticaria.

EENT

Exophthalmos, glaucoma, increased IOP, posterior subcapsular cataracts.

Electrolytes

Fluid retention, hypokalemic alkalosis, potassium loss, sodium retention.

Endocrine

Decreased carbohydrate and glucose tolerance, development of cushingoid state, glycosuria, hirsutism, hyperglycemia, hypertrichosis, increased requirements for insulin or oral hypoglycemic agents in diabetes, manifestation of latent diabetes mellitus, menstrual irregularities, secondary adrenocortical and pituitary unresponsiveness, suppression of growth in children.

GI

Abdominal distention, hiccups, nausea, pancreatitis, peptic ulcer and possible perforation and hemorrhage, perforation of the small and large intestine, ulcerative esophagitis.

Genitourinary

Decreased or increased motility and number of spermatozoa.

Hepatic

Elevation in serum liver enzyme levels, hepatomegaly.

Hypersensitivity

Anaphylactoid reactions, anaphylaxis, angioedema.

Metabolic-Nutritional

Abnormal fat deposits, moon face, negative nitrogen balance caused by protein catabolism, weight gain.

Musculoskeletal

Aseptic necrosis of femoral and humeral heads, loss of muscle mass, muscle weakness, osteoporosis, pathologic fracture of long bones, steroid myopathy, tendon rapture, vertebral compression fractures.

Miscellaneous

Decreased resistance to infection, edema.

Precautions

Pregnancy

Category C

Lactation

Excreted in breast milk.

Children

May be more susceptible to adverse reactions from topical use than adults. Observe growth and development of infants and children on prolonged therapy.

Ophthalmic solution and suspension

Safety and efficacy not established in children.

Elderly

May require lower doses. Use with caution, usually starting at the low end of the dosage range because of the greater frequency of decreased hepatic, renal, or cardiac function, and of concomitant diseases or other drug therapy.

Ophthalmic suspension

No differences in safety and efficacy have been observed between elderly and younger patients.

Renal Function

Use cautiously; monitor renal function.

Sulfite Sensitivity

Some products may contain sodium bisulfite, which may cause allergic-type reactions in some individuals.

Adrenal suppression

Prolonged therapy may lead to hypothalamic-pituitary-adrenal suppression.

Fluid and electrolyte balance

Can cause elevated BP, salt and water retention, and increased potassium and calcium excretion. Dietary salt restriction and potassium supplementation may be needed.

GI

Because of increased risk of perforation, use with caution in patients with diverticulitis, fresh intestinal anastomosis, latent peptic ulcers, or nonspecific ulcerative colitis.

Hepatitis

May be harmful in chronic active hepatitis positive for hepatitis B surface antigen.

Infections

May mask signs of infection. May decrease host-defense mechanisms to prevent dissemination of infection.

Musculoskeletal

Bone formation may be decreased and bone resorption may be increased.

Neuropsychiatric

Psychic or psychotic manifestations may occur, including euphoria, insomnia, personality changes, and severe depression; in addition, emotional instability or psychotic tendencies may be exacerbated.

Ocular effects

Use systemically with caution in ocular herpes simplex because of possible corneal perforation.

Ophthalmic use

Prolonged use may result in glaucoma or other complications.

Stress

Increased dosage of rapidly acting corticosteroid may be needed before, during, and after stressful situations.

Withdrawal

Abrupt discontinuation may result in adrenal insufficiency. Discontinue gradually.

Overdosage

Symptoms

Acne, anorexia, arthralgia, central obesity, diabetes, dizziness, dyspnea, ecchymoses, electrolyte and fluid imbalance (chronic cushingoid changes), fainting, fever, hirsutism, hyperlipidemia, hypertension, hypoglycemia (acute overdose), infection, malaise, moon face, myalgia, myopathy, nausea, orthostatic hypotension, osteoporosis, peptic ulcer, sexual dysfunction, skin desquamation, striae.

Patient Information

Caution patient that stopping drug abruptly is dangerous and may cause adrenal insufficiency.
Explain rationale for tapering off medication when that time comes.
Instruct patient to avoid exposure to chickenpox or measles and to immediately notify health care provider if exposure occurs.
Teach patient or family procedures for correctly administering specific form of drug (eg, ophthalmic).
Caution patient against receiving immunizations while drug is being taken.
Advise patient on long-term therapy to carry medication identification (eg, card, bracelet). In case of emergency, this information is important for treatment.
Instruct patient to avoid people with infections, particularly respiratory.
Teach patient to take oral forms with meals or snacks if GI irritation occurs.
Review guidelines for missed doses of particular product with patient.
Teach patient on long-term therapy how to keep a weight record.
Instruct patient to inform other health care providers if taking a steroid.
Review signs of infection and remind patient that fever, swelling, and redness may be masked in infection.
Review possible adverse reactions of dexamethasone with patient and instruct patient to report these to health care provider.