Salmeterol

Generic Name: Salmeterol Xinafoate

Brand Names: Serevent

Salmeterol is a long-acting beta-agonist for maintenance treatment of asthma and COPD, not for acute symptoms.

RespiratoryLABABronchodilator

Drug Class

Long-Acting Beta-2 Adrenergic Agonist (LABA)

Pregnancy

Category C; no adequate well-controlled studies in pregnant women. Animal studies showed teratogenic effects at very high doses. Use during pregnancy only if the potential benefit justifies the potential risk. Poorly controlled asthma poses its own pregnancy risks.

Available Forms

50 mcg/blister inhalation powder (Serevent Diskus)

What It's Used For

Dosage Quick Reference

These are general dosage guidelines. Your doctor will determine the appropriate dose for your specific situation.

Condition	Starting Dose	Maintenance Dose
Asthma (adults and children ≥ 4 years)	1 inhalation (50 mcg) twice daily, every 12 hours	50 mcg twice daily; must always be used with an inhaled corticosteroid (ICS)
COPD (maintenance)	1 inhalation (50 mcg) twice daily, every 12 hours	50 mcg twice daily
Exercise-Induced Bronchospasm (prevention)	1 inhalation (50 mcg) at least 30 minutes before exercise	50 mcg before exercise; do not use if already on twice-daily salmeterol

Side Effects

Common Side Effects:

Headache
Pharyngitis
Nasal congestion
Upper respiratory tract infection
Cough
Throat irritation

Serious Side Effects:

Asthma-related death (when used without ICS)
Paradoxical bronchospasm
Cardiovascular effects (tachycardia, arrhythmias)
Hypokalemia
Hyperglycemia

Drug Interactions

Beta-blockers (propranolol, metoprolol, atenolol): Non-selective beta-blockers can antagonize the bronchodilator effect of salmeterol and may provoke severe bronchospasm in asthma patients. If a beta-blocker is needed, cardioselective agents are preferred with caution.
Strong CYP3A4 inhibitors (ketoconazole, ritonavir, clarithromycin): Co-administration with ketoconazole significantly increased salmeterol systemic exposure in studies, increasing the risk of cardiovascular side effects (QT prolongation, palpitations). Avoid combination.
MAO inhibitors and tricyclic antidepressants: These can potentiate the cardiovascular effects of salmeterol (hypertension, tachycardia, arrhythmias). Use extreme caution if combined.
Other long-acting beta-agonists (formoterol, vilanterol, olodaterol): Do not use two LABAs together. This does not increase efficacy but increases the risk of cardiovascular adverse effects.
QT-prolonging medications (sotalol, amiodarone, certain fluoroquinolones): Salmeterol can prolong the QTc interval; combining it with other QT-prolonging agents increases the risk of serious arrhythmias.

Additional Information

Salmeterol is a long-acting beta-2 adrenergic agonist (LABA) used for maintenance treatment of asthma and chronic obstructive pulmonary disease (COPD). It provides sustained bronchodilation and is always used in combination with an inhaled corticosteroid for asthma.

Mechanism of Action

Salmeterol works through beta-2 receptor stimulation:

Beta-2 receptor agonism: Binds to beta-2 receptors on bronchial smooth muscle
Increased cyclic AMP: Activates adenylyl cyclase, increasing intracellular cAMP
Bronchial smooth muscle relaxation: cAMP-dependent protein kinase mediates relaxation
Long duration of action: Lipophilic side chain allows prolonged receptor binding
Duration: ~12 hours of bronchodilation

Onset is slower than short-acting beta-agonists (15-20 minutes vs 5 minutes).

Available Formulations

Dry powder inhaler (Serevent Diskus): 50 mcg per inhalation
Combination products:
- Salmeterol/fluticasone (Advair Diskus, Advair HFA)
- Salmeterol/fluticasone (Wixela Inhub, AirDuo RespiClick)

Medical Uses

FDA-Approved Indications:

Asthma maintenance treatment in patients ≥4 years (in combination with inhaled corticosteroid only)
Prevention of exercise-induced bronchospasm (EIB) in patients ≥4 years
Maintenance treatment of COPD including chronic bronchitis and emphysema

Important: For asthma, salmeterol must be used with an inhaled corticosteroid (ICS).

Dosing Guidelines

Asthma Maintenance (with ICS):

Adults and children ≥4 years: 50 mcg (one inhalation) twice daily, approximately 12 hours apart

COPD Maintenance:

50 mcg twice daily, approximately 12 hours apart

Exercise-Induced Bronchospasm:

50 mcg at least 30 minutes before exercise
Do not use additional doses for 12 hours
Patients already on twice-daily dosing should not use additional doses for EIB prevention

Important Safety Information

Black Box Warning:

Asthma-related death: LABAs increase the risk of asthma-related death. This risk may be mitigated by using LABAs with ICS.
Use only in combination with an ICS for asthma
Do not use for acute bronchospasm

Contraindications:

Acute asthma or COPD exacerbation
Hypersensitivity to salmeterol or any component

Warnings and Precautions:

Not for acute symptoms (use short-acting beta-agonist)
Paradoxical bronchospasm may occur
Cardiovascular effects: May cause increased pulse, blood pressure, or arrhythmias
Hypokalemia possible
Hyperglycemia in diabetic patients

Drug Interactions

Strong CYP3A4 inhibitors (ketoconazole, ritonavir): May increase cardiovascular adverse effects; use with caution
Beta-blockers: May antagonize effects; use cardioselective beta-blockers with caution
Diuretics (non-potassium-sparing): May worsen hypokalemia
MAO inhibitors, tricyclic antidepressants: May potentiate cardiovascular effects

Special Populations

Hepatic Impairment: Use with caution (limited data)
Pregnancy: Use only if benefit outweighs risk
Lactation: Unknown if excreted in milk
Pediatric: Approved for ≥4 years with ICS for asthma; EIB in ≥4 years
Elderly: No specific adjustment

Frequently Asked Questions

No. Salmeterol is a long-acting maintenance medication that takes 15 to 20 minutes to start working. It should never be used for acute asthma attacks or sudden shortness of breath. Always carry a separate short-acting rescue inhaler (such as albuterol) for emergency use.

The FDA black box warning states that LABAs like salmeterol increase the risk of asthma-related death when used without an inhaled corticosteroid (ICS). This is why salmeterol should always be prescribed together with an ICS for asthma patients. When used in combination with an ICS, the risk is not significantly elevated. For COPD, this specific warning does not apply.

Open the Diskus by sliding the thumbgrip until it clicks. Slide the lever until it clicks to load a dose. Breathe out fully (away from the device), then place the mouthpiece to your lips and inhale steadily and deeply. Remove the inhaler, hold your breath for about 10 seconds, then breathe out slowly. Close the Diskus after use. Do not wash the Diskus; keep it dry.

Combination inhalers like fluticasone/salmeterol (Advair) ensure you always take both medications together, improving adherence and safety. Many doctors prefer combination inhalers for this reason. Your doctor can determine whether a combination or separate inhalers is the best approach for you.

Questions to Ask Your Doctor

Consider discussing these topics at your next appointment:

✓Am I also on an inhaled corticosteroid, as required when using salmeterol for asthma?
✓Could I switch to a combination inhaler for better adherence?
✓How often should I be using my rescue inhaler, and does the frequency suggest my asthma is not well controlled?
✓Should my lung function be retested to see if salmeterol is providing adequate control?

Schedule an Appointment

Related Health Conditions

This medication is commonly used to treat or manage the following conditions:

Asthma

Asthma, a chronic lung disease, causes airway inflammation and narrowing, resulting in wheezing, coughing, and shortness of breath, triggered by allergens, irritants, infections, or stress.

Learn More

Chronic Obstructive Pulmonary Disease (COPD)

COPD, a progressive lung disease causing irreversible airflow limitation, encompassing emphysema and chronic bronchitis, is primarily driven by irritant exposure like smoking, leading to shortness of breath and chronic cough.

Learn More

Medical Disclaimer: This information is for educational purposes only and should not be considered medical advice. Always consult with your healthcare provider before starting, stopping, or changing any medication. Your doctor can provide personalized recommendations based on your specific health condition and medical history.