Alpha-2 adrenergic receptor agonist

An overview of alpha-2 adrenergic receptor agonists, their mechanisms, uses, and related topics.

Alpha-2 adrenergic receptor agonists are a class of pharmacological agents that primarily act on the alpha-2 adrenergic receptors in the central nervous system and peripheral nervous system. These receptors are part of the adrenergic receptor family, which are G protein-coupled receptors involved in the regulation of various physiological processes.

Mechanism of Action

Alpha-2 adrenergic receptors are located both pre- and post-synaptically. When activated by an agonist, these receptors inhibit the release of norepinephrine and other neurotransmitters, leading to a decrease in sympathetic nervous system activity. This results in effects such as reduced blood pressure, sedation, and analgesia.

Clinical Uses

Alpha-2 adrenergic receptor agonists are used in a variety of clinical settings:

• Hypertension: Drugs like clonidine and methyldopa are used to lower blood pressure by reducing sympathetic outflow from the central nervous system.
• Sedation and Anesthesia: Dexmedetomidine is used for its sedative properties in intensive care settings and during surgical procedures.
• Attention Deficit Hyperactivity Disorder (ADHD): Guanfacine and clonidine are used as adjunctive treatments for ADHD.
• Opioid Withdrawal: Clonidine is sometimes used to alleviate withdrawal symptoms in patients undergoing opioid detoxification.

Side Effects

Common side effects of alpha-2 adrenergic receptor agonists include:

• Hypotension
• Bradycardia
• Sedation
• Dry mouth
• Dizziness

Examples of Alpha-2 Adrenergic Receptor Agonists

• Clonidine
• Dexmedetomidine
• Guanfacine
• Methyldopa

Also see

• Adrenergic receptor
• Sympathetic nervous system
• G protein-coupled receptor
• Hypertension
• Sedation