Isoproterenol hydrochloride (Medihaler-Iso®) is a beta adrenergic receptor agonist medication, used as an inhaled aerosol to treat asthma. Although it activates all beta adrenergic receptors, it works in a similar fashion to the more selective beta2-adrenergic receptor agonists by relaxing the airways to increase airflow.
It is also supplied in ampules under the brand name IsuprelĀ® for injection and in sublingual pill form for treatment of asthma, chronic bronchitis and emphysema.
It is structurally similar to epinephrine but acts for the most part on beta receptors.
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Isoproterenol - Familydoctor.org - Information for patients in English and Spanish.