Salmeterol

Pronunciation: sal-ME-ter-ol
Class: Sympathomimetic

Trade Names

Serevent Diskus
- Powder for inhalation 50 mcg (as salmeterol xinafoate)

Pharmacology

Produces bronchodilation by relaxing bronchial smooth muscle through beta-2 receptor stimulation.

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Pharmacokinetics

Absorption

Salmeterol acts locally in the lung. Plasma levels do not predict therapeutic effect. Depending on dose, T _max is 20 min and mean C _max is 167 pg/mL.

Distribution

Protein binding is 96%; xinafoate moiety is greater than 99%.

Metabolism

Extensively metabolized by hydroxylation.

Elimination

Eliminated in feces (60%) and urine (25%); half—life is 5.5 days. Xinafoate moiety half-life is 11 days.

Special Populations

Has not been studied in patients with renal impairment.

May lead to accumulation of salmeterol in plasma.

Has not been studied in elderly patients.

Indications and Usage

Treatment of asthma and prevention of bronchospasm; prevention of exercise-induced bronchospasm (EIB); maintenance treatment of bronchospasm associated with COPD (including emphysema and chronic bronchitis).

Contraindications

Use without a concomitant long-term asthma control medication (eg, inhaled corticosteroid) for the treatment of asthma; hypersensitivity to salmeterol or product components.

Dosage and Administration

Inhalation 1 inhalation (50 mcg) twice daily, approximately 12 h apart.

Inhalation 1 inhalation at least 30 min before exercise; additional doses should not be used for at least 12 h.

Inhalation 1 inhalation (50 mcg) twice daily, approximately 12 h apart.

General Advice

• For oral inhalation only.
• When initiating therapy in patients receiving oral or inhaled corticosteroids, continue patients on a suitable dose of corticosteroids; make any changes in corticosteroid dosage only after clinical evaluation.
• Do not exhale into the inhalation device.
• Only activate and use the inhalation device in a level, horizontal position.
• Do not use a spacer.
• Do not exceed recommended dosage.

Storage/Stability

Store between 68° and 77°F in a dry place. Protect from direct heat or sunlight. Discard 6 wk after removal from moisture-protective foil pouch or when the dose indicator reads “0.”

Drug Interactions

Pulmonary effects of salmeterol may be blocked by beta-blockers and may produce severe bronchospasm in patients with COPD. If coadministration cannot be avoided, cardioselective beta-blockers could be considered, but administer them with caution.

Salmeterol plasma concentrations may be elevated, increasing the pharmacologic effects and risk of adverse reactions. In addition, coadministration of salmeterol and ketoconazole may increase the QTc interval. Because of the potential increased risk of CV adverse reactions, coadministration of salmeterol and strong CYP3A4 inhibitors is not recommended.

Coadministration may increase salmeterol C _max , resulting in increases in heart rate and QTc interval. Coadminister with caution and closely monitor for CV adverse reactions.

Other long-acting beta-2 agonists will have additive effects with salmeterol, increasing the risk of asthma-related death. Do not use salmeterol with other medications containing a long-acting beta-2 agonist.

May increase CV effects of salmeterol. If coadministration cannot be avoided, give salmeterol with extreme caution to patients being treated with MAOIs or TCAs or within 2 wk of discontinuing an MAOI or TCA.

ECG changes and hypokalemia associated with diuretics may worsen with coadministration, especially when the recommended dose of the beta-agonist is exceeded. Coadminister with caution.

Adverse Reactions

Cardiovascular

Hypertension (4%); palpitations, tachycardia; arrhythmias, including atrial fibrillation, extrasystoles, and supraventricular tachycardia (postmarketing).

CNS

Headache (17%); dizziness (4%); anxiety, migraine, nervousness, paresthesia, sleep disturbance (1% to 3%); tremor.

Dermatologic

Rash (4%); urticaria (3%); contact dermatitis, eczema (1% to 3%); photodermatitis (1% to 2%).

EENT

Nasal sinus congestion, pallor (9%); throat irritation (7%); pharyngitis (6%); rhinitis (5%); ear signs/symptoms, nasal blockage/congestion, sinusitis (4%); conjunctivitis, keratitis, sinus headache (1% to 3%).

GI

Nausea/vomiting (3%); dental pain, dyspepsia, GI infections, hyposalivation, oral/throat candidiasis, oral mucosal abnormality (1% to 3%); GI signs/symptoms (1% to 2%).

Hypersensitivity

Immediate hypersensitivity reactions (eg, angioedema, bronchospasm, rash); anaphylaxis (postmarketing).

Musculoskeletal

Skeletal muscle pain (12%); muscle cramps/spasms (3%); arthralgia, articular rheumatism, bone/skeletal pain, inflammation, muscle pain, muscle stiffness, pain in joints, tightness, rigidity (1% to 3%).

Respiratory

Bronchitis, tracheitis (7%); cough, viral respiratory tract infection (5%); asthma (4%); lower respiratory signs/symptoms (1% to 2%); irritation or swelling (including stridor or choking), laryngeal spasm, oropharyngeal irritation, paradoxical bronchospasm, serious exacerbations of asthma (some fatal) (postmarketing).

Miscellaneous

Influenza (5%); edema, fever, hyperglycemia, localized aches and pains, pain, swelling (1% to 3%).

Precautions

Pregnancy

Category C .

Lactation

Undetermined.

Children

Safety and efficacy for children younger than 4 y of age not established.

Elderly

Observe special caution in elderly patients with CV disorders.

Hypersensitivity

Allergic reactions can occur after administration.

Hepatic Function

Closely monitor these patients.

Acute or worsening asthma events

Do not use salmeterol to treat acute symptoms; short-acting beta-2 adrenergic agonists should be used.

CV effects

Use with caution in patients with CV disease (eg, cardiac arrhythmias, coronary insufficiency, hypertension); toxic symptoms may occur. ECG changes (eg, flattening of T wave, QTc prolongation, ST segment depression) have occurred; clinical significance is unknown.

Excessive use

Paradoxical bronchospasm and cardiac arrest have been associated with excessive inhalant use. The recommended dosage should not be exceeded.

Hypokalemia

Decreases in potassium levels may occur.

Paradoxical bronchospasm

Life-threatening paradoxical bronchospasm may occur.

Special risk

Use with caution in patients with convulsive disorders or thyrotoxicosis, or who are unusually responsive to sympathomimetic amines.

Overdosage

Symptoms

Arrhythmias and/or tachycardia, cardiac arrest, death, headache, hyperglycemia, hypokalemia, muscle cramps, palpitations, prolongation of the QTc interval, tremor.

Patient Information

• Instruct patients to read the Medication Guide before starting therapy and with each refill.
• Instruct patient on the proper storage, handling, and use of the dry powder inhaler, referring to the patient information leaflet included with the medication.
• Advise patient that medication should never be administered with a spacer device.
• Caution patient not to exceed prescribed dose. Inform patient that medication is still inhaled even if it is not tasted or felt when delivered.
• Instruct patient not to stop the medication once symptoms have been controlled. Continued daily use is necessary to continue control of symptoms.
• Advise patient not to change the dose or stop using unless advised by health care provider.
• Caution patient not to use other salmeterol-containing products or other long-acting bronchodilators while using salmeterol.
• Warn patient that salmeterol is a maintenance medication and is not to be used to treat an acute asthma attack. “Rescue medication” (short-acting bronchodilator) must be used to obtain rapid relief of asthma symptoms.
• Advise patient using salmeterol for prevention of EIB to take medication at least 30 min before exercise and to wait 12 h before using again.
• Advise patient that medication does not replace inhaled or oral corticosteroids and to continue to use as prescribed by health care provider.
• Advise patient not to increase dose and to inform health care provider if symptoms do not improve or worsen, if more inhalations than usual of the short-acting bronchodilator are needed, or if the short-acting bronchodilator appears to become less effective.
• Advise patient to carry medical identification (eg, card, bracelet) if they experience acute severe asthma attacks requiring rapid systemic treatment.
• Advise patient to report the following symptoms to health care provider: chest pain, nervousness, palpitations, persistent cough, rapid heart rate, sore throat or mouth, tremor, worsening asthma symptoms.

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