Isocarboxazid
Severe
Textbook
Increased risk of adverse cardiovascular effects.
At least 2 weeks should elapse between the use of MAO inhibitors and administration of β2 agonists or other sympathomimetics.
Source: G&G 14e · p264
Drug reference
metaproterenol
β2-selective adrenergic receptor agonist · Bronchodilator
β2-selective adrenergic receptor agonistBronchodilator
CDSCO approved
EXCRETION
—
not curated
INTERACTIONS
7 major
SEVERE in our sources
PREGNANCY
—
not curated
Top interactionssee all 9 →
- IsocarboxazidSevereTextbookG&G 14e · p264
- MoclobemideSevereTextbookG&G 14e · p264
- PhenelzineSevereTextbookG&G 14e · p264
- ProcarbazineSevereTextbookG&G 14e · p264
Mechanism
Metaproterenol is a resorcinol bronchodilator with hydroxyl groups at positions 3 and 5 of the phenyl ring, making it resistant to methylation by COMT. It is considered β2 selective, causing relaxation of bronchial smooth muscle.
Indications
long-term treatment of obstructive airway diseasesasthmaacute bronchospasmBronchodilation (as last resort)
Pharmacokinetics
Onset
within minutes of inhalation; slower orally
Bioavailability
substantial fraction (40%) absorbed in active form after oral administration
Protein binding
effects persist for several hours (inhalation), 3 to 4 hours (oral)
Excretion
primarily as glucuronic acid conjugates
Side effects
Common
cardiac stimulation
Drug interactions
Moclobemide
Severe
Textbook
Increased risk of adverse cardiovascular effects.
At least 2 weeks should elapse between the use of MAO inhibitors and administration of β2 agonists or other sympathomimetics.
Source: G&G 14e · p264
Phenelzine
Severe
Textbook
Increased risk of adverse cardiovascular effects.
At least 2 weeks should elapse between the use of MAO inhibitors and administration of β2 agonists or other sympathomimetics.
Source: G&G 14e · p264
Procarbazine
Severe
Textbook
Increased risk of adverse cardiovascular effects.
At least 2 weeks should elapse between the use of MAO inhibitors and administration of β2 agonists or other sympathomimetics.
Source: G&G 14e · p264
Rasagiline
Severe
Textbook
Increased risk of adverse cardiovascular effects.
At least 2 weeks should elapse between the use of MAO inhibitors and administration of β2 agonists or other sympathomimetics.
Source: G&G 14e · p264
Selegiline
Severe
Textbook
Increased risk of adverse cardiovascular effects.
At least 2 weeks should elapse between the use of MAO inhibitors and administration of β2 agonists or other sympathomimetics.
Source: G&G 14e · p264
Tranylcypromine
Severe
Textbook
Increased risk of adverse cardiovascular effects.
At least 2 weeks should elapse between the use of MAO inhibitors and administration of β2 agonists or other sympathomimetics.
Source: G&G 14e · p264
Corticosteroids
Moderate
Textbook
Enhanced beneficial effects in asthma therapy for both drugs.
Source: G&G 14e · p887
Digoxin
Moderate
Textbook
Hypokalemia, which could predispose to cardiac arrhythmias, especially in patients with cardiac disease.
Use with caution.
Source: G&G 14e · p264
Related guidelines
Other β2-selective adrenergic receptor agonist drugs
Ask House about metaproterenol
Continue into a citation-backed clinical answer with the drug context already attached.
Sources: Goodman & Gilman 14e·Verified: 2026-05-10 · House clinical team