6.9:
Adrenergic Agonists: Therapeutic Classification
Adrenergic agonists are classified based on their mechanism of action. Additionally, sympathomimetics can also be categorized by their therapeutic actions.
Pressor agents, or vasopressors, are used to elevate low blood pressure. These include endogenous catecholamines, such as noradrenaline, and synthetic agents like phenylephrine.
They also serve as cardiac stimulants by increasing the heart rate, the force of contractility, and conduction velocity.
Bronchodilators include β2-agonists such as salbutamol and terbutaline. They relax lung muscles and widen the airways, making breathing easier.
α-agonists like oxymetazoline and phenylephrine act as decongestants. They help relieve nasal congestion and clear blocked noses.
Noncatecholamine sympathomimetics, such as amphetamine, act as CNS stimulants. They induce restlessness, euphoria, and insomnia through the release of DA and serotonin.
β2-agonists like ritodrine are used to relax the uterus and delay premature labor.
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.