Discriminate the category of medications and individual medications, by the following three types of information: Type (or types) or receptor(s) through which the drug acts (e.g. alpha 1, alpha 2, beta 1, beta 2, etc.). Normal response to the activation of those receptors (agonist vs. antagonists). What the drug in question does to the receptor function.

Type (or types) or receptor(s) through which the drug acts (e.g. alpha 1, alpha 2, beta 1, beta 2, etc.): Drug categories like alpha 1, alpha 2, beta 1, beta 2 are adrenergic receptors of the peripheral nervous system.

Normal response to the activation of those receptors (agonist vs. antagonists).

These are more specific and are activated by epinephrine, norepinephrine, and Dopamine selectively. They interact with the receptors and binds with them to produce the fight or flight response.

Adrenergic agonists stimulate the activity of adrenergic receptors.

adrenergic antagonists inhibit the activity of adrenergic receptors.

What the drug in question does to the receptor function:

Adrenergic drugs work by stimulating sympathetic nervous system nerves to respond to stress or emergency situations. They are generally used bronchodilators, vasopressors, or cardiac stimulators.