ALUPENT
Clinical safety rating: caution
Comprehensive clinical and safety monograph for ALUPENT (ALUPENT).
Beta-2 adrenergic receptor agonist; relaxes bronchial smooth muscle, leading to bronchodilation.
| Metabolism | Metabolized via conjugation and oxidation; enzymes include sulfotransferases and monoamine oxidase (MAO). |
| Excretion | Renal excretion of unchanged drug and metabolites accounts for approximately 40-60% of the dose, with the remainder eliminated via biliary/fecal routes. Following oral administration, about 30-40% is recovered in urine as unchanged drug and glucuronide conjugates, and 50-60% in feces. After intravenous administration, renal elimination is 40-50% unchanged, with biliary excretion contributing 30-40%. |
| Half-life | The terminal elimination half-life of metaproterenol (Alupent) is approximately 2.5–5 hours after oral administration, and 2–4 hours after intravenous or inhaled routes. Its relatively short half-life supports dosing every 4–6 hours for bronchodilator effect. |
| Protein binding | Approximately 50–70% bound to plasma proteins, primarily albumin. |
| Volume of Distribution | The volume of distribution (Vd) is approximately 1.5–2.5 L/kg, indicating extensive distribution into tissues, including the lungs and smooth muscle. |
| Bioavailability | Oral: 40–60% due to first-pass metabolism; Inhaled: 10–20% of the delivered dose reaches the systemic circulation; Intravenous and subcutaneous: 100%. |
| Onset of Action | Oral: 15–30 minutes; Inhalation (metered-dose inhaler): 5–15 minutes; Subcutaneous: 5–15 minutes; Intravenous: 1–5 minutes. |
| Duration of Action | Bronchodilation lasts 4–6 hours after oral or inhaled administration, with maximum effect at 1–2 hours. Tolerance may develop with regular use, decreasing duration of action. |
| Action Class | Short acting β2-agonists |
| Brand Substitutes | Orcibest Tablet |
Inhalation: 2 inhalations (0.65 mg per inhalation) every 3-4 hours, up to 12 inhalations per day. Oral: 20 mg three to four times daily.
| Dosage form | AEROSOL, METERED |
| Renal impairment | eGFR < 30 mL/min: consider dose reduction by 50% or increase dosing interval to every 8 hours. |
| Liver impairment | Child-Pugh Class B or C: reduce dose by 50% and monitor for toxicity. |
| Pediatric use | Inhalation (≥6 years): 1-2 inhalations every 4 hours, max 8 inhalations/day. Oral (6-14 years): 10 mg three times daily; (2-5 years): 5 mg three times daily. |
| Geriatric use | Start at lowest effective dose (e.g., 10 mg oral twice daily) and titrate slowly due to increased sensitivity to beta-agonists and higher risk of adverse effects. |
| 1st trimester | Consult provider |
| 2nd trimester | Consult provider |
| 3rd trimester | Consult provider |
Clinical note
Comprehensive clinical and safety monograph for ALUPENT (ALUPENT).
| Breastfeeding | Excreted in human milk; M/P ratio not established. Use with caution due to potential for infant tachycardia and hypoglycemia. Consider alternative agents with more safety data (e.g., albuterol). |
| Teratogenic Risk | Pregnancy Category C. In first trimester, meta-analysis shows no increased risk of major congenital malformations. Second and third trimesters: beta-2 agonists may cause fetal tachycardia, hypoglycemia, and hypocalcemia; risk of premature labor suppression if used late in pregnancy. Limited human data; animal studies show no teratogenicity at high doses. |
■ FDA Black Box Warning
None
| Serious Effects |
["Hypersensitivity to metaproterenol or any component","Tachyarrhythmias"]
| Precautions | ["Paradoxical bronchospasm","Cardiovascular effects (tachycardia, hypertension)","Hypokalemia","Hyperglycemia","Tremor","Nervousness"] |
| Food/Dietary | No significant food interactions. Caffeine may increase nervousness and palpitations; limit intake. Avoid alcohol as it may worsen side effects. |
| Clinical Pearls | Alupent (metaproterenol) is a beta-2 adrenergic agonist used as a bronchodilator. It is less selective than albuterol, so monitor for tachycardia and tremor. Avoid in patients with tachyarrhythmias. Use with caution in diabetes and hyperthyroidism. Overuse may lead to paradoxical bronchospasm. |
Loading safety data…
| Fetal Monitoring |
| Monitor maternal heart rate, blood pressure, serum glucose, and electrolytes. Fetal monitoring for heart rate and growth if used chronically. Assess for signs of preterm labor suppression. |
| Fertility Effects | No evidence of direct impairment of fertility. Beta-agonists may transiently affect uterine contractility but no known persistent effect on conception or ovarian function. |
| Patient Advice | Use exactly as prescribed; do not increase dose or frequency. · Rinse mouth after inhalation to prevent oral thrush. · Seek immediate medical help if symptoms worsen or you need more doses than usual. · Avoid getting spray into eyes; if occurs, flush with water. · Report palpitations, chest pain, or severe nervousness to your doctor. |