Question

Which is the centrally acting alpha 2 agonist muscle relaxant

• A. Diazepam
• B. Bromocriptine
• C. Tizanidine
• D. Methocarbamol

Answer 1

The Correct Option is C

In pharmacology, understanding the mechanism of action of medications is crucial for their effective use. Among the options given, we need to identify which drug acts as a centrally acting alpha-2 agonist muscle relaxant.

Let's evaluate the provided options:

• Diazepam: A benzodiazepine that enhances the effect of the neurotransmitter GABA at the GABA_A receptor, leading to muscle relaxation, sedation, and anxiolytic effects. It works through a different mechanism and is not an alpha-2 agonist.
• Bromocriptine: A dopamine agonist primarily used in the treatment of Parkinson's disease and certain pituitary tumors. It does not function as a muscle relaxant nor as an alpha-2 agonist.
• Tizanidine: This drug is known to be a centrally acting muscle relaxant that works as an alpha-2 adrenergic receptor agonist. It decreases spasticity by inhibiting presynaptic motor neurons.
• Methocarbamol: This is generally classified as a skeletal muscle relaxant that acts on the central nervous system but does not work through alpha-2 adrenergic receptors.

Based on this analysis, Tizanidine is the correct answer, as it specifically acts as a centrally acting alpha-2 adrenergic agonist to produce muscle relaxation.