Sedative hypnotics and anxiolytic drugs

Question 1

What is a sedative effect?

Answer 1

– The general, nonspecific inhibition of
CNS, resulting in reduced irritability
and agitation and leading to
drowsiness.

Question 2

What is a hypnotic effect?

Answer 2

effect: sleep-inducing
– Most of the sedative drugs at higher
doses induce sleep
– Drug-induced sleep is not identical to
normal physiological sleep, mainly in
that the normal structure of sleep is
disturbed to a different extent by
different drugs

Question 3

What is an anxiolytic effect?

Answer 3

– The specific relief of anxiety, fear,
tension and apprehension, without
significant general inhibition of CNS.

Question 4

Anxiolytic and sedative-hypnotic drugs:

classification

Answer 4

• Benzodiazepines (BDZ)
– Sedative-hypnotic
• BDZ-like hypnotic drugs (Z drugs)
– Anxiolytics

• Others
– 5-HT1A receptor agonists:
• Buspirone
– Barbiturates
– Melatonin analogs
– Orexin antagonists
– With different structure
• Hydroxizine
• Etifoxine
• Tofisopam

Question 5

What is the mechanism of action of benzodiazepines?

Answer 5

• BDZs potentiate GABA-A receptor
stimulation
– Increase affinity of GABA to its binding site
– Increase the frequency of opening the ionic
channel in the presence of GABA
• Determinants of BDZ-sensitive GABA-A
receptors:
– α subunits (α1 α2 α3
and α5
): define the specific
effects of stimulation
– γ2
subunit: defines the sensitivity
• BDZ-binding sites at GABA-A receptors:
– BZ1
(ω1
) (α12
γ2
) – sedative-hypnotic
– BZ2
(ω2
) – different combinations of α2
, α3
and α5 with  and γ2
subunits – anxiolytic
– BZ3
(ω3
) – peripheral type: in pancreas, adrenal
medulla, etc.