Pharmacology · single question
What is the Mechanism of Action of Clonazepam?
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Correct answer: A. Enhance GABA-A receptor activity (positive allosteric modulator)
Enhance GABA-A receptor activity (A). Clonazepam (and all benzodiazepines) are positive allosteric modulators of GABA-A receptors:
• GABA is the major inhibitory neurotransmitter in the CNS.
• Benzodiazepines bind to the benzodiazepine site on GABA-A receptor → increase the FREQUENCY of Cl⁻ channel opening → enhanced inhibition → CNS depression.
• Uses of clonazepam: seizures (particularly absence seizures, myoclonic seizures), panic disorder, anxiety.
• Remember: Benzodiazepines increase FREQUENCY of Cl⁻ opening; Barbiturates increase DURATION.
• Dental relevance: patients on benzodiazepines → sedation risk when combined with dental sedation agents; xerostomia.
• Reversal agent: Flumazenil (GABA-A antagonist at benzodiazepine site).
• GABA is the major inhibitory neurotransmitter in the CNS.
• Benzodiazepines bind to the benzodiazepine site on GABA-A receptor → increase the FREQUENCY of Cl⁻ channel opening → enhanced inhibition → CNS depression.
• Uses of clonazepam: seizures (particularly absence seizures, myoclonic seizures), panic disorder, anxiety.
• Remember: Benzodiazepines increase FREQUENCY of Cl⁻ opening; Barbiturates increase DURATION.
• Dental relevance: patients on benzodiazepines → sedation risk when combined with dental sedation agents; xerostomia.
• Reversal agent: Flumazenil (GABA-A antagonist at benzodiazepine site).