Adult: As metered dose aerosol or dry powd inhaler: 50 mcg bid.
Chống chỉ định
Monotherapy in the treatment of asthma. Treatment of status asthmaticus, other acute episodes of asthma or COPD.
Patient w/ CV disease, CNS disorders, DM, hyperthyroidism, hypokalaemia, seizure disorders, ketoacidosis. Not intended for the relief of acute bronchospasm. Hepatic impairment. Pregnancy and lactation.
Monitor pulmonary function, BP, heart rate, CNS stimulation, hepatic function; glucose and K levels.
Symptoms: Dizziness, HTN or hypotension, tremor, headache, tachycardia, hypokalaemia, seizures, angina, arrhythmias, nervousness, muscle cramps, dry mouth, palpitations, nausea, fatigue, malaise, insomnia, hyperglycaemia, metabolic acidosis. Management: Symptomatic and supportive treatment. β-blockers may be considered but should be used w/ caution.
Increased risk of CV effects w/ potent CYP3A4 inhibitors (e.g. ketoconazole, ritonavir). Reduced bronchodilatory effect w/ β-blockers. Increased risk of hypokalaemia w/ non K-sparing diuretics. MAOIs and TCAs may potentiate the effect of salmeterol on vascular system.
Description: Salmeterol stimulates intracellular adenyl cyclase, the enzyme that catalyses the conversion of ATP to cyclic-3',5'-adenosine monophosphate (cAMP) resulting in relaxation of bronchial smooth muscle and inhibition of release of mediators of immediate hypersensitivity from mast cells. Onset: Asthma: 30-48 min. COPD: 2 hr. Duration: Approx 12 hr. Pharmacokinetics: Absorption: Low or undetectable systemic absorption. Time to peak plasma concentration: Approx 20 min. Distribution: Plasma protein binding: 96%. Metabolism: Extensively metabolised via hydroxylation to α-hydroxy-salmeterol by CYP3A4 isoenzyme. Excretion: Via faeces (60%), urine (25%). Half-life: 5.5 hr.
Store between 20-25°C. Protect from heat or sunlight.