| Receptor Agonists & Antagonists | |
| Alpha 1 | |
| Agonist | Antagonist |
| Systemic vasoconstrictor | Systemic vasodilator (decreases norepinephrine response) |
| Treats shock or low blood pressure | Treats benign prostatic hypertrophy (BPH) |
| Example - Norepinephrine | Example - Phentalomine |
| Alpha 2 | |
| Agonist | Antagonist |
| Decreases sympathetic output from CNS - lowers blood pressure | None |
| Treats hypertension | |
| Example - Clonidine | |
| Non-specific Beta 1&2 | |
| Agonist | Antagonist |
| Beta 1 - Elevates heart rate, increases AV nodal conduction | Beta 1 - Decreases heart rate, oxygen consumption, and lowers blood pressure |
| Beta 2 - Bronchodilator | Beta 2 - Bronchoconstrictor |
| Beta 1 - Treats AV block and bradycardia | Beta 1 - Treats hypertension, and reduce angina |
| Beta 2 - Treats asthma | Beta 2 - Can cause asthma |
| Example - Isoproterinol | Example - Propranolol |
| Cardioselective Beta 1 Blockers | |
| Agonist | Antagonist |
| None | Decreases heart rate, and oxygen consumption |
| Treats hypertension, and angina | |
| Example - Metoprolol, Atenolol | |
| Pulmonary Selective Beta 2 | |
| Agonist | Antagonist |
| Bronchodilator | None |
| Treats asthma | |
| Example - Albuterol | |
| Muscurinic | |
| Agonist | Antagonist |
| Increases contractions of smooth muscle, decreases heart rate, and increases secretions of exocrine glands | Decreases GI activity, and secretions; increases heart rate and force |
| Treats GI stasis, and paroxysmal atrial tachycardia (PAT) | Treats GI or GU spasms, dry secretions, and used for pre-op |
| Examples - Acetylcholine, Methacholine, Carbacholine, Uricholine | Examples - Atropine, Scopolamine |
| Nicotinic (Ganglia) | |
| Agonist | Antagonist |
| None | Decrease sympathetic tone to heart and blood vessels; decrease blood pressure dramatically |
| Treats hypertensive crisis | |
| Example - Trimethoprim | |
| Nicotinic (Skeletal muscle) | |
| Agonist | Antagonist |
| Inhibits acetylcholinase, and elevates acetylcholine at skeletal muscle sites | Decrease skeletal muscle activity at neuro-muscular junction (blockers) |
| Treats myasthenia gravis and spasms; antagonist of the blockers (curare) | Used for surgery, and mysthenia gravis diagnosis |
| Examples - Physostigmine, Neostigmine | Example - Succinylcholine (Curare) |
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