Hello awesomites!! So, here are my "Single page notes" on sedative-hypnotics. To the end of this post I have uploaded picture of my notes. So lets begin.
Classification:It is classified into 3 categories.
1)Barbiturates
Key points :
a) No antidote.Poisoning treated by gastric lavage, symptomatic treatment and forced alkaline diuresis
b) Steep curve dose.
c) Inhibits all areas of CNS. Most sensitive is reticular system
d) It inhibits all areas of CNS. Mostly reticular system which leads to inability to maintain wakefullness.
e) May cause "Hyperalgesia".
f) Duration of REM sleep and stage 3, 4 of sleep cycle decreases
g) Contraindictated in acute intermittent porphyria
i) Hangover is common
Barbiturates are further classified into three types.
A) Long acting
Phenobarbitone.
B) Short acting.
Butobarbitone
Pentobarbitone.
C) Ultra short acting
Thiopentone.
Methohexitone.
2)Benzodiazepines
Key points:
a) Antidote:Flumazenil is competitive antagonist. It takes 30-60 minutes for its action.
b) Flat dose curve.
c) Duration of REM sleep decreases but frequency increases.
d) Hangover less common
They are further classified into three categories
A) Hypnotics
-Diazepam:Causes analgesia(Barbiturates causes hyperalgesia as mentioned earlier.) and it also causes muscle relaxation
-Flurazepam :Paradoxical simulation and increase nightmare
-Nitrazepam:Increase REM sleep (Rest decreases)
-Temazepam
-Flunitrazepam : Tasteless BZD called as "
" Date rape drug"
-Midazolam:Causes blackouts and ataxia.
-Alprazolam
-Triazolam:Responsible for paranoia and other psychiatric disturbances.
B)Anti-anxiety
Remember OLA-CD
-Oxazepam
-Lorazepam:Absorption from intramuscular site is regular for other drugs its irregular.
-Alprazolam
-Chlordiazepoxide.
-Diazepam.
C) Anti-convulsants :
-Diazepam
-Lorazepam
-Clonazepam
-Clobazam
Remember: EasT LOT
E=Estazolam
T=Temazepam
L=Lorazepam
O=Oxazepam
T=Triazolam
These drugs directly conjugated without metabolism to active products. These are short acting and can be used in liver failure
3)Newer non-benzodiazepine hypnotics:
-Zopiclone:
a) Increases stage 3 and stage 4 duration
b) Indicated for patients BZDs for induction of sleep
c) Less rebound insomnia and hangover.
b) Active metabolite is eszopiclone.
-Zolpidem
a) Lacks anti-anxiety, muscle relaxants, and anti-convulsants actions.
b) Use in short term treatment of insomnia.
c) No rebound insomnia and hangover.
-Zaleplon
a) Decreases sleep latency without affecting sleep time.
-Suvorexant:
a) Its is Orexin antagonist. Orexin is wake-fullness receptor.
Ojas
