The document discusses various classes of sedative and hypnotic drugs including benzodiazepines, barbiturates, and newer agents. It describes how these drugs work in the central nervous system by facilitating the action of the inhibitory neurotransmitter GABA. The document also covers the pharmacokinetics, uses, adverse effects, and treatment of overdose for different sedative and hypnotic medications.

1. Presented By: Ms. Kalaivani Sathish M. Pharm
Assistant Professor,
PIMS - Panipat
SEDATIVES
&
HYPNOTICS

2. SEDATIVE & HYPNOTICS
 Sedative is a drug that produces
calming or quietening effect and
reduces excitement, it may induce
drowsiness.
 Hypnotics is a drug that induces
sleep, resembling natural sleep.

3. CLASSIFICATION
I. Benzodiazepines
 Long Acting – 24 – 48 Hrs (Diazepam,
Clonazepam, Chlordiazepoxide)
 Short Acting – 12 – 24 Hrs (Nitrazepam,
Lorazepam and Alprazolam)
 Ultra Short Acting - < than 6 Hrs (Triazolam,
Midazolam)
II. Newer agents – Zolpidam,Zopiclone

4. CLASSIFICATION (Cont...)
III. Barbiturates – Thiopentone,
Phenobarbitone, Mephobarbitone,
Pentobarbitone.
IV. Miscellaneous – Paraldehyde,
Chloral Hydrate

5. BENZODIAZEPINE
 Chlordiazepoxide was the first BZD.
 Pharmacological Action
 It includes
1. Sedation and Hypnosis
2. Reduction in anxiety
3. Anesthetic
4. Muscle Relaxation
5. Anti – Convulsion effect
6. Amnesia

6. MECHANISM OF ACTION
Gamma-aminobutric acid(GABA) is the
principle inhibitory neurotransmitter of the
CNS and it acts through GABA
receptors.BZD bind to the GABA-A receptor
and increase the frequency of chloride
channel opening.this inturn leads to
increased flow of chloride into the
neurons,resulting in hyperpolarization.

7. In CNS (GABA)
BZD binds with GABA – A Receptors
Increase the Frequency of Cl – Ions Channel Opening
Increase the Flow of Cl – into the neurons
Hyperpolarisation

8. BZDAS HYPNOTICS WHENCOMPAREDTO
BARBITURATES
1.BZD induce sleep which more resembles
natural sleep and has less hangover.
2.In hypnotic doses they do not affect respiration
or cardiovascular function.
3.BZD have safer than barbiturates even in over
doses.
4.In case overdose a specific BZD antagonist –
flumazenil can be used to reverse the symptoms.

9. BZDAS HYPNOTICS WHENCOMPAREDTO
BARBITURATES
5. BZD do not cause microsomsal enzyme
induction and therefore do not alter the
blood level of other drug.
6.BZD have lower abuse liability.

10. pharmacokinectics
BZD are completely absorbed on oral
administration .IM absorption is slow hence
oral route is preferred. they are extensively
bound to plasm protein metabolized in the
liver.

11. Absorbed well in Orally
Binds with plasma protein
Metabolized in Liver
Excreted by kidney

12. Adverseeffect
Drowsiness, confusion, amnesia, lethargy,
weakness, headache, blurred vision,
ataxia, day time sedation, while on BZD
driving should be avoided.

13. uses
1.Insomnia
2.In anxiety status
3.Anticonvulsant
4.Muscle relaxant
5.As pre anesthetic medication
6.During alcohol withdrawal
7.General anesthesia
8.In psychiatry

14. BZD ANTAGONIST
FLUMAZENIL
It is a BZD receptor antagonist .given IV
flumazenil is rapid and short acting.it may
rarely induce seizures.
USES
1. To reverse BZD sedation / anesthesia.
2. In BZD overdosage.

15. neweragent
ZOLPIDEM
It is a good hypnotic but has weak
anticonvulsant.and muscle relaxant effect. It is
Short acting but sleep continue for a long time.
ESZOPICLONE
It is metabolized by hepatic microsomal
enzymes,adverse effects dryness of mouth
,metalic taste.

16. Neweragent uses
The newer drugs have similar efficacy as
BZD in the treatment of
insomnia.minimum day after
drowsiness and less amnesia.

17. Barbiturates classification
Barbiturates are derivative of barbituric acid .
It can be classified based on the duration of
action,
1.Long acting-
Phenobarbitone,mephobarbotone.
2.Short acting –
Pentobarbitone,butobarbitone.
3.Ultra short acting-
Thiopentone,hexobarbitone.

18. Mechanism of action
Barbiturates bind to a specific site on the
GABA receptor and facilitate inhibitory
neurotransmission by opening chloride ion
channels and hyperpolarize the neural
membrane.

19. In CNS (GABA)
BZD binds with GABA – A Receptors
Increase the Frequency of Cl – Ions Channel Opening
Increase the Flow of Cl – into the neurons
Inhibits neurotransmission
&
Hyperpolarisation

20. Pharmacokinectics
1. Barbiturates are well absorbed and widely
distributed in the body.
2. The highly lipid soluble barbiturates like
thiopentone have a fast onset of action .
3. It metabolized in liver.
4. The metabolites are excreted in urine.

21. Absorbed well in Orally
Binds with plasma protein
Metabolized in Liver
Excreted in urine

22. Adverse reaction
Nausea, vomitting,vertigo ,and diarrhea,
respiratory depression, skin rashes
,swelling of the eyelids and lips.

23. Tolerance and dependence
On repeated administration tolerance
develops to the effect of barbiturates
developement of both psychological
physiologocal dependence to
Barbiturates.

24. Acute barbiturates poisoning
The fatal dose of barbiturates is 6-10grams.
Symptoms- respiratory depression,slow
and shallow breathing ,hypotension,skin
eruption,cardiovascular collapse,and
renal failure.

25. treatment
There is no specific antidote.
1.Gastric lavage followed by administration of
activated charcoal to prevent further
absorption of barbiturates.
2.General supportive measures like maintenance
of BP,adequate ventillation and oxygen
administration.
3.Forced alkaline diuresis.
4.Hemodialysis should be done especially if there
is renal failure.

26. miscellaneous
MELATONIN:
The hormone secreted by the pineal gland is known to
regulate sleep.melatonin act on melatonin
recepors.it does not depress the CNS it improves
the quality of sleep and helps in withdrawing BZD
after long term use.
RAMELTEON:
It is an agonist at the melatonin receptors is a novel
hypnotic drug.it does not modify the sleep .the
duration of action is prolonged .adverse effect
dizziness and fatigue.

27. miscellaneous
CHORAL HYDRATE
It is used as an alternative to BZD .It has a bad taste
and is an irritant causes nausea and vomitting.
It produce hypnosis without affecting
respiatory and cardiovasular funtion.
PARALDEHYDE
It is a colourless,transperant,pungent,inflammable
liquid. It is an irritant and can dissolve plastic
cannot be given by aplastic syringe.it also has
anticonvulsant properties.

28. miscellaneous
PARALDEHYDE
It is given rectally ,IM,or orally.
USES
1.AS Convulsant in status epilepticus particularly in
children.
2. Hypnotic rarely used.