Albuterol sulfate

albuterol sulfate

(al byoo' ter ole)

AccuNeb, Novo-Salmol (CAN), Proventil, Proventil HFA, Salbutamol (CAN), Ventodisk (CAN), Ventolin HFA

Pregnancy Category C

Drug classes

Sympathomimetic

Beta₂-selective adrenergic agonist

Bronchodilator

Antasthmatic

Therapeutic actions

In low doses, acts relatively selectively at beta₂-adrenergic receptors to cause bronchodilation and vasodilation; at higher doses, beta₂ selectivity is lost, and the drug acts at beta₂ receptors to cause typical sympathomimetic cardiac effects.

Indications

·        Relief and prevention of bronchospasm in patients with reversible obstructive airway disease

·        Inhalation: Treatment of acute attacks of bronchospasm

·        Prevention of exercise-induced bronchospasm

·        Unlabeled use: Adjunct in treating serious hyperkalemia in dialysis patients; seems to lower potassium concentrations when inhaled by patients on hemodialysis

Contraindications and cautions

·        Contraindicated with hypersensitivity to albuterol; tachyarrhythmias, tachycardia caused by digitalis intoxication; general anesthesia with halogenated hydrocarbons or cyclopropane (these sensitize the myocardium to catecholamines); unstable vasomotor system disorders; hypertension; coronary insufficiency, CAD; history of stroke; COPD patients with degenerative heart disease.

·        Use cautiously with diabetes mellitus (large IV doses can aggravate diabetes and ketoacidosis); hyperthyroidism; history of seizure disorders; psychoneurotic individuals; labor and delivery (oral use has delayed second stage of labor; parenteral use of beta₂-adrenergic agonists can accelerate fetal heart beat and cause hypoglycemia, hypokalemia, pulmonary edema in the mother and hypoglycemia in the neonate); lactation; the elderly (more sensitive to CNS effects).

Available forms

Tablets—2, 4 mg; syrup—2 mg/5 mL; aerosol—90 mcg/actuation; solution for inhalation—0.083%, 0.5%, 1.25 mg/3 mL, 0.63 mg/3 mL; capsules for inhalation—200 mcg

Dosages

ADULTS

Oral

Initially, 2 or 4 mg (1–2 tsp syrup) tid–qid PO; may cautiously increase dosage if necessary to 4 or 8 mg qid, not to exceed 32 mg/day.

Inhalation

Each actuation of aerosol dispenser delivers 90 mcg albuterol; 2 inhalations q 4–6 hr; some patients may require only 1 inhalation q 4 hr; more frequent administration or larger number of inhalations not recommended.

·        Prevention of exercise-induced bronchospasm: 2 inhalations 15 min prior to exercise.

Solution for inhalation

2.5 mg tid to qid by nebulization.

Inhalation capsules

One 200 mcg capsule q 4–6 hr up to two 200 mcg capsules q 4–6 hr.

·        Prevention of exercise-induced asthma: One 200 mcg capsule inhaled 15 min before exercise.

PEDIATRIC PATIENTS

Oral, tablets

6–12 yr: 2 mg tid–qid. Do not exceed 24 mg/day.

> 12 yr: Use adult dosage.

Oral, syrup

< 2 yr: Safety and efficacy not established.

2–6 yr: Initially, 0.1 mg/kg tid, not to exceed 2 mg (1 tsp) tid; if necessary, cautiously increase stepwise to 0.2 mg/kg tid. Do not exceed 4 mg (2 tsp) tid.

6–14 yr: 2 mg (1 tsp) tid–qid; if necessary, cautiously increase dosage. Do not exceed 24 mg/day in divided doses.

> 14 yr: Use adult dosage.

Inhalation

2–12 yr: For child 10–15 kg, use 1.25 mg; for child > 15 kg, use 2.5 mg.

> 12 yr: Use adult dosage.

Solution for inhalation

10–15 kg: 1.25 mg bid or tid by nebulization.

> 15 kg: 2.5 mg bid or tid by nebulization.

Inhalation capsules

> 4 yr: One 200 mcg capsule inhaled q 4–6 hr.

·        Prevention of exercise-induced asthma: One 200 mcg capsule inhaled 15 min before exercise.

GERIATRIC PATIENTS OR PATIENTS SENSITIVE TO BETA-ADRENERGIC STIMULATION

Restrict initial dose to 2 mg tid or qid; individualize dosage thereafter. Patients > 60 yr are more likely to develop adverse effects.

Pharmacokinetics

Route	Onset	Peak	Duration
Oral	30 min	2–2.5 hr	4–8 hr
Inhalation	5 min	1.5–2 hr	3–8 hr

Metabolism: Hepatic; T_1/2: 2–4 hr

Distribution: Crosses placenta; enters breast milk

Excretion: Urine

Adverse effects

·        CNS: Restlessness, apprehension, anxiety, fear, CNS stimulation, hyperkinesia, insomnia, tremor, drowsiness, irritability, weakness, vertigo, headache

·        CV: Cardiac arrhythmias, tachycardia, palpitations, PVCs (rare), anginal pain

·        Dermatologic: Sweating, pallor, flushing

·        GI: Nausea, vomiting, heartburn, unusual or bad taste in mouth

·        GU: Increased incidence of leiomyomas of uterus when given in higher than human doses in preclinical studies

·        Respiratory: Respiratory difficulties, pulmonary edema, coughing, bronchospasm, paradoxical airway resistance with repeated, excessive use of inhalation preparations

Interactions

Drug-drug

·        Increased sympathomimetic effects with other sympathomimetic drugs

·        Increased risk of toxicity, especially cardiac, when used with theophylline, aminophylline, oxtriphylline

·        Decreased bronchodilating effects with beta-adrenergic blockers (eg, propranolol)

·        Decreased effectiveness of insulin, oral hypoglycemic drugs

·        Decreased serum levels and therapeutic effects of digoxin

Nursing considerations

Assessment

·        History: Hypersensitivity to albuterol; tachyarrhythmias, tachycardia caused by digitalis intoxication; general anesthesia with halogenated hydrocarbons or cyclopropane; unstable vasomotor system disorders; hypertension; coronary insufficiency, CAD; history of stroke; COPD patients who have developed degenerative heart disease; diabetes mellitus; hyperthyroidism; history of seizure disorders; psychoneurotic individuals; lactation

·        Physical: Weight; skin color, T, turgor; orientation, reflexes, affect; P, BP; R, adventitious sounds; blood and urine glucose, serum electrolytes, thyroid function tests, ECG

Interventions

·        Use minimal doses for minimal periods; drug tolerance can occur with prolonged use.

·        Maintain a beta-adrenergic blocker (cardioselective beta-blocker, such as atenolol, should be used with respiratory distress) on standby in case cardiac arrhythmias occur.

·        Prepare solution for inhalation by diluting 0.5 mL 0.5% solution with 2.5 mL normal saline; deliver over 5–15 min by nebulization.

·        Do not exceed recommended dosage; administer pressurized inhalation drug forms during second half of inspiration, because the airways are open wider and the aerosol distribution is more extensive.

Teaching points

·        Do not exceed recommended dosage; adverse effects or loss of effectiveness may result. Read the instructions that come with respiratory inhalant.

·        You may experience these side effects: Dizziness, drowsiness, fatigue, headache (use caution if driving or performing tasks that require alertness); nausea, vomiting, change in taste (eat frequent small meals); rapid heart rate, anxiety, sweating, flushing, insomnia.

·        Report chest pain, dizziness, insomnia, weakness, tremors or irregular heart beat, difficulty breathing, productive cough, failure to respond to usual dosage.

Adverse effects in Italic are most common; those in Bold are life-threatening.