sedative -hypnotics

1. Pharmacology
Sedative-hypnotics
Slide-7

2. Channels in the CNS

3. Neurotransmitters in the CNS:
• Dopamine
• Acetylcholine
• Serotonin
• Nor-epinephrine
• GABA
• Glutamate and Aspartate
• Opioid peptides

5. Definition and general idea
• Drugs that produce sedation in small doses and
sleep in larger doses (hypnosis)
• Sleep requirements :
• Teenagers need about 10 hours per day.
• Adults about 8 hours sleep per day.
• Elderly need about 6 hours a day.

6. Failing to sleep
• Anxiety and stress
• Depression
• Pain
• Some physical illnesses like heart failure and
chronic lung diseases bcz it causes discomfort in
breathing.
• Caffeine, alcohol and steriods.

7. Inducing sleep by:
• Walking
• Bath
• Drink glass of milk at bed time.

8. Sleep cycle

9. Sleep cycle
• First hour of sleep called non-REM stage leading
to a state of deep sleep (REM stage) last about
90 min.
• Dreaming phase about 10 min after REM-stage.
• This cycle repeated about 6 times per night.

10. Important definitions
• Addiction: The state of response to a drug whereby the
drug taker feels compelled to use the drug and suffers
anxiety when separated from it. Removal of the drug
evokes unpleasant, possibly life-threatening symptoms,
often the opposite of the drug’s effects.
• Anxiolytic: A drug that reduces anxiety, a sedative.
• Hypnosis: Induction of sleep.
• Sedation: Reduction of anxiety.

11. Introduction
• A sedative drug (anxiolytic) reduce anxiety and
exert a calming effect.
• A hypnotic drug produces drowsiness and
facilitates the onset and maintenance of a state
of sleep that resembles natural sleep (dose-
dependent).
• Most anxiolytic and sedative–hypnotic
drugs produce dose - dependent
depression of CNS function.

12. Types
• The main group of drugs are as follows:
• 1-Benzodiazepines (anxiolytic and hypnotic).
• 2-Barbiturates (their used is now confined to
anesthesia and epilepsy).
• 3-Miscellaneous agents.

13. A. Benzodiazepines
• Receptors for benzodiazepines (BZ receptors) are present in
many brain regions.
• They have largely replaced barbiturates and meprobamate in
the treatment of anxiety, b/c they are safer and more effective.
• The most prominent of these effects are:
• -sedation ,
• -hypnosis ,
• -decreased
• -anxiety ,
• -muscle
• -relaxation ,

14. Hypnotic drugs
• 1-chloral hydrate:
• Rapidly absorbed and produce sleep in about
30min and lasts about 4 hours.
• Unpleasant taste, gastric irritant.
• Safe but can cause stomach upset.
• Concurrent administration with warfarin
increase the effect of warfarin given with
caution in patients with liver or renal failure.

15. Hypnotic drugs
• 2-Promethazine :
• Can cause dry mouth and may interfere with
bladder function (decrease the activity)
• 3-clomethiazole:
• Rarely used bcz its so addictive.
• Given orally or I.V , short duration of action.
• Can cause respiratory distress upon I.V
injection.

16. • Benzodiazepines are:
• -Diazepam (valium)
• -Oxazepam
• -Lorazepam
• -Chlordiazepxide
• -Temazepam
• -Flurazepam
• -Nitrazepam
• Etc….

17. BDZs
• 1- Nitrazepam :
• First benzodiazepine to be used as hypnotic.
• Sedation effect can persist to the following day.
• 2-Diazepam (valium)
• Mainly used as anxiolytic but also a good
hypnotic depending on the dose.
• Sedative effect last to the next day.

18. BDZs
• 3-Temazepam:
• Shorter half life, and quite longer duration than
the others.
• Less side effects during the next day.
• 4-Flurazepam :
• Tasteless and have long duration of action.

19. Other clinical uses:
• benzodiazepines (eg, diazepam) are used as
components of anesthesia protocols including those used
in day surgery.
• management of seizure disorders (eg, clonazepam)
and bipolar disorder (eg, clonazepam).

20. Other uses:
• Longer acting benzodiazepines (eg, chlordiazepoxide,
diazepam) are used in the management of withdrawal
states in persons physiologically dependent on ethanol
and other sedative-hypnotics.

21. Antagonist:
• Antagonists: Flumazenil (blocks the actions of
bzd, zolpidem, zaleplon….but not that of
barbiturates).
• The drug is available for IV administration only
• Onset is rapid but duration is short.
• Adverse effects: Agitation, confusion, dizziness,
and nausea.

22. Adverse effects:
• No serious side effects of adverse effects.
• Include: drowsiness, sometimes a significant impact
on driving ability, job performance, and personal
relationships.
• Stepwise discontinuation of the drug.

23. Special circumstances
• In renal failure Nitrazepam is satisfactory but
small doses should be used initially.
• In liver failure Temazepam used with care.
• In respiratory distress all sedative-hypnotics
produce some respiratory depression should be
used with care if necessary.