What is an example of an alpha 2 (alpha 2) agonist?

From the Guidelines

Dexmedetomidine is a highly effective alpha 2 agonist, particularly in intensive care settings, as evidenced by its ability to provide sedation with minimal respiratory depression 1.

Key Characteristics of Alpha 2 Agonists

• Alpha 2 agonists work by stimulating alpha 2 receptors in the brain stem, reducing sympathetic outflow from the central nervous system.
• This leads to decreased blood pressure, heart rate, and peripheral vascular resistance.
• Other alpha 2 agonists include clonidine, guanfacine, and tizanidine, each with different specific applications, potency, and duration of effect.

Clinical Applications

• Dexmedetomidine is primarily used for sedation in intensive care settings due to its unique properties, such as minimal respiratory depression and the ability to provide a pattern of sedation that allows patients to be more easily arousable and interactive 1.
• Clonidine is used for hypertension, attention deficit hyperactivity disorder (ADHD), and managing withdrawal symptoms from substances like opioids.
• Guanfacine is used for ADHD and hypertension, with a documented higher specificity to alpha-2A receptors, which may mediate differences in adverse effects profiles compared to clonidine 1.

Important Considerations

• The choice of alpha 2 agonist depends on the specific clinical scenario, including the patient's condition, the desired outcome, and potential side effects.
• Dexmedetomidine's unique profile makes it an ideal choice for sedation in critically ill patients, where the risk of respiratory depression is a significant concern 1.

From the FDA Drug Label

Dexmedetomidine is a potent non-narcotic alpha2-adrenoceptor agonist which produces sedation and analgesia. DEXDOMITOR (dexmedetomidine hydrochloride) is a synthetic alpha2-adrenoreceptor agonist with sedative and analgesic properties.

• Dexmedetomidine is an example of an alpha 2 agonist 2, 2.

From the Research

Alpha 2 Agonists

• Clonidine is an example of an alpha 2 agonist, as mentioned in studies 3, 4, 5, 6, 7
• Guanfacine is another alpha 2 agonist, which binds more selectively to alpha(2A)-receptors, as stated in the study 4

Mechanism of Action

• Alpha 2 agonists reduce arousal by decreasing the firing of noradrenaline neurons in locus ceruleus, as explained in the study 4
• They may work in a synergistic fashion with stimulants through regulation of prefrontal cortex function, as mentioned in the study 6

Clinical Applications

• Alpha 2 agonists have been used to treat attention-deficit/hyperactivity disorder (ADHD), as discussed in studies 4, 5, 6, 7
• They have also been used to treat hypertension, Tourette's syndrome, developmental disorders, and substance abuse, as mentioned in the studies 3, 4