6.9 : Adrenergic Agonists: Therapeutic Classification

Adrenergic agonists can be classified based on their therapeutic uses and mechanisms of action. They serve various purposes in clinical applications.

Vasopressor or pressor agents: They increase blood pressure and function as cardiac stimulants. Examples include endogenous catecholamines (norepinephrine and dopamine) and synthetic agents (phenylephrine).

Bronchodilators: β₂-agonists can relax bronchial muscles and widen airways. They are commonly used for treating obstructive pulmonary disorders and asthma.

Decongestants: To alleviate nasal congestion, α-agonists like oxymetazoline and phenylephrine are commonly used for relieving stuffy or blocked noses and sinuses.

Indirect-acting CNS stimulants: Agents like amphetamine and analogs lacking the catechol moiety act as CNS stimulants. They induce restlessness, euphoria, and insomnia by triggering neurotransmitter release. Some agents function as appetite suppressants.

Uterine relaxants: Specific β₂-agonists like ritodrine delay premature labor by relaxing the uterus.

Incontinence treatment: β₃-agonists like mirabegron are employed to treat urinary incontinence.

Adrenergic agonists have diverse roles in clinical applications, serving specific therapeutic purposes in various conditions.