02/10/2021
dexamethasone
INDICATIONS
Used systemically and locally in a wide variety of chronic diseases including: Inflammatory, Allergic, Hematologic, Endocrine, Neoplastic, Dermatologic, Autoimmune disorders, Management of cerebral edema, Diagnostic agent in adrenal disorders. Unlabeled Uses: Short-term administration to high-risk mothers before delivery to prevent respiratory distress syndrome in the newborn. Adjunctive management of nausea and vomiting from chemotherapy. Treatment of airway edema prior to extubation. Used in neonates with bronchopulmonary dysplasia to facilitate ventilator weaning.
ACTION
In pharmacologic doses, suppresses inflammation and the normal immune response. Has numerous intense metabolic effects (see Adverse Reactions and Side Effects). Suppresses adrenal function at chronic doses of 0.75 mg/day. Has negligible mineralocorticoid activity. Therapeutic Effects: Suppression of inflammation and modification of the normal immune response.
PHARMACOKINETICS
Absorption: Well absorbed after oral administration. Sodium phosphate salt is rapidly absorbed after IM administration. Absorption from local sites (intra-articular, intralesional) is slow but complete.
Distribution: Widely distributed, crosses the placenta, and appears to enter breast milk.
Metabolism and Excretion: Mostly metabolized by the liver.
Half-life: Low birth weight infants with BPD: 9.3 hr; Children 3 mo–16 yr: 4.3 hr; Adults: 3–4.5 hr (plasma), 36–54 hr (tissue); adrenal suppression lasts 2.75 days.
CONTRAINDICATIONS AND PRECAUTIONS
Contraindicated in: Active untreated infections (may be used in patients being treated for tuberculous meningitis); Known alcohol or bisulfite hypersensitivity or intolerance (some products contain these and should be avoided in susceptible patients); Lactation: Avoid chronic use.
Use Cautiously in: Chronic treatment (will lead to adrenal suppression; use lowest possible dose for shortest period of time); Stress (surgery, infections); supplemental doses may be needed; Potential infections (may mask signs); OB: Safety not established; Pedi: Early postnatal administration of high doses can cause significant and persistent reductions in neuromotor and cognitive functioning; results in ↓ growth; use lowest possible dose for shortest period of time.
ADVERSE REACTIONS AND SIDE EFFECTS
Adverse reactions/side effects are much more common with high-dose/long-term therapy
CNS: depression, euphoria, hallucinations, headache, ↑ intracranial pressure (children only), insomnia, personality changes, psychoses, restlessness. EENT: cataracts, ↑ intraocular pressure. CV: hypertension, edema. GI: PEPTIC ULCERATION, anorexia, nausea, ↑ appetite, vomiting. Derm: acne, ↓ wound healing, ecchymoses, hirsutism, petechiae. Endo: adrenal suppression, hyperglycemia. F and E: amenorrhea, hypokalemia, alkalosis. Hemat: THROMBOEMBOLISM, thrombophlebitis. Metab: weight gain. MS: muscle wasting, osteoporosis, avascular necrosis of joints, muscle pain. Misc: cushingoid appearance (moon face, buffalo hump), ↑ susceptibility to infection.
INTERACTIONS
Drug-Drug: ↑ risk of hypokalemia with thiazide and loop diuretics, amphotericin B, piperacillin, or ticarcillin. Hypokalemia may ↑ risk of digoxin toxicity. May ↑ requirement for insulin or oral hypoglycemic agents. May ↓ levels ofphenytoin and isoniazid. Levels may be ↑ with oral contraceptives. ↑ risk of adverse GI effects with NSAIDs (including aspirin),alcohol and caffeine. At chronic doses that suppress adrenal function, may ↓ the antibody response to and ↑ risk of adverse reactions from live-virus vaccines. May ↑ or ↓ the effects of warfarin. Levels may be ↓ when used with phenytoin, phenobarbital, or rifampin. May ↑risk of tendon rupture when used with fluoroquinolones.
ROUTE/DOSAGE
PO: IM: IV: (Adults ): Anti-inflammatory—0.75–9 mg daily in divided doses q 6–12 hr. Airway edema or extubation—0.5–2 mg/kg/day divided q 6 hr; begin 24 hr prior to extubation and continue for 24 hr post-extubation. Cerebral edema—10 mg IV, then 4 mg IM or IV q 6 hr until maximal response achieved, then switch to PO regimen and taper over 5–7 days.
PO: IM: IV: (Children ): Airway edema or extubation—0.5–2 mg/kg/day divided q 6 hr; begin 24 hr prior to extubation and continue for 24 hr post-extubation. Anti-inflammatory—0.08–0.3 mg/kg/day or 2.5–10 mg/m2/day divided q 6–12 hr. Physiologic replacement—0.03–0.15 mg/kg/day or 0.6–0.75 mg/m2/day divided q 6–12 hr.
PO: (Adults ): Suppression test—1 mg at 11pm or 0.5 mg q 6 hr for 48 hr.
IV: (Children ): Chemotherapy induced emesis—5–20 mg given 15–30 min before treatment. Cerebral edema—Loading dose 1–2 mg/kg followed by 1–1.5 mg/kg/day divided q 4–6 hr for 5 days (not to exceed 16 mg/day); then taper over 1–6 wk. Bacterial meningitis—0.6 mg/kg/day divided q 6 hr x 4 days (start at time of first antibiotic dose).
IV: PO: (Adults ): Chemotherapy induced emesis—10–20 mg given 15–30 min before each treatment or 10 mg q 12 hr on each treatment day. Delayed nausea/vomiting—4–10 mg PO 1–2 times/day for 2–4 days or 8 mg PO q 12 hr for 2 days, then 4 mg PO q 12 hr for 2 days or 20 mg PO 1 hr before chemotherapy, then 10 mg PO q 12 hr after chemotherapy, then 8 mg PO q 12 hr for 2 days, then 4 mg PO q 12 hr for 2 days.
Intrasinovial (Adults ): 0.4–6 mg/day.
AVAILABILITY (GENERIC AVAILABLE)
Tablets 0.5 mg, 0.75 mg, 1 mg, 1.5 mg, 2 mg, 4 mg, 6 mg; Elixir(raspberry flavor) 0.5 mg/5 mL; Oral solution(cherry flavor) 0.5 mg/5 mLL, 1 mg/mL; Solution for injection (sodium phosphate) 4 mg/mL, 10 mg/mL;
NURSING IMPLICATIONS
ASSESSMENT
Indicated for many conditions. Assess involved systems before and periodically during therapy.
Assess for signs of adrenal insufficiency (hypotension, weight loss, weakness, nausea, vomiting, anorexia, lethargy, confusion, restlessness) before and periodically during therapy.
Monitor intake and output ratios and daily weights. Observe patient for peripheral edema, steady weight gain, rales/crackles, or dyspnea. Notify physician or other health care professional should these occur.
Children should have periodic evaluations of growth.
Cerebral Edema: Assess for changes in level of consciousness and headache throughout therapy.
Lab Test Considerations: Monitor serum electrolytes and glucose. May cause hyperglycemia, especially in patients with diabetes. Monitor hematologic values, serum electrolytes, and serum and urine glucose in patients on prolonged therapy. May cause ↓ WBC counts. May cause ↓ serum potassium and calcium and ↑ serum sodium concentrations.
Guaiac test stools. Promptly report presence of guaiac-positive stools.
May cause ↑ serum cholesterol and lipid values. May ↓ uptake of thyroid 123I or 131I.
Suppresses reactions to allergy skin tests.
Periodic adrenal function tests may be ordered to assess degree of hypothalamic-pituitary-adrenal axis suppression in systemic and chronic topical therapy.
Dexamethasone Suppression Test: To diagnose Cushing's syndrome, obtain baseline cortisol level; administer dexamethasone at 11 pm and obtain cortisol levels at 8 am the next day. Normal response is a decreased cortisol level.
Alternative method: Obtain baseline 24-hr urine for 17-hydroxycorticosteroid (OHCS) concentrations, then begin 48-hr administration of dexamethasone. Second 24-hr urine for 17-OHCS is obtained after 24 hr of dexamethasone.
POTENTIAL NURSING DIAGNOSES
Risk for infection (Side Effects)
Disturbed body image (Side Effects)
IMPLEMENTATION
If dose is ordered daily or every other day, administer in the morning to coincide with the body's normal secretion of cortisol.
Periods of stress, such as surgery, may require supplemental systemic corticosteroids.
PO: Administer with meals to minimize GI irritation. Tablets may be crushed and administered with soft food, chocolate syrup, or fluids for patients with difficulty swallowing. Use calibrated measuring device to ensure accurate dosage of liquid forms.
IM: IM doses should not be administered when rapid effect is desirable. Do not dilute with other solution or admix.
IV Administration
pH: 7.0–8.5.
Direct IV: Diluent: May be given undiluted. Concentration: 4–10 mg/mL. Rate: Administer over 1–4 min if dose is
