The document discusses various classes of analgesics, including opioid and non-opioid types, highlighting specific compounds such as codeine, meperidine, and fentanyl, along with their structural modifications and corresponding analgesic activities. It also covers narcotic antagonists that block the effects of opioids, detailing their mechanisms and medical applications, particularly in overdose situations. Key findings include the potency and effectiveness of modified compounds compared to traditional morphine derivatives.

1. NARCOTIC AND NON
NARCOTIC ANALGESIC

2. • Agents that produce analgesia
• Analgesia – state of relative insensitivity to
pain.
• Capacity to tolerate pain is increased without
loss of consciousness

3. Classification
• Opioid Analgesic
• Non opioid analgesic

12. CODEINE
• One tenth analgesic as morphine
• Free phenolic grp. Is important for greater
potency.
H3CO
N
CH3
O
OH

13. MEPERIDINE HCl
• Discovered in 1930
• Analgesic propeties observed during pharmacological work up.
• Replacement of C4 phenyl group of meperidine by H, alkyl, aryl and
heterocyclic group decreases analgesic activity.
• Introduction of m-OH on phenyl ring increases the activity.
• Presence of phenyl and ester group at 4th position of 1-methyl piperidine
results in optimal activity.
• Replacement of carberhoxy group in meperidine by acyloxy group gives
better activity.
N
COOC 2H5
CH3

14. Anileridine
• Replacement of 4-phenyl group by hydrogen, aroalkyl or
heterocyclic grp. Results in reduced activity.
• Replacement of COOC2H5 BY OCOC2H5 gives better activity.
• 4 times more active than meperidine.
N
COOC2H5
N
H2

15. DIPHENOXYLATE
• It is weak opioid agonist
• Available combined with atropine.
• Diphenylmethane and CN moeity is imp.
• Ester metabolised to carboxylic acid which is active opioid
agent.
N
COOC 2H5
H5C6
H5C6
CN

16. LOPERAMIDE HCl
N
OH
Cl
(H5C6)2
O
N
C
H3
CH3
Acts on mu receptor in the myenteric plexus of the large
intestine.
Effective for the treatment of Diarrhea.

17. FENTANYL CITRATE
• Phenyl ring and acyl group are seperated from
the ring by nitrogen.
N
O
C2H5
N
CH2CH2C6H5

18. METHADONE HCl
• Simplification of morphine nucleus by opening
of nitrogen ring results in methadone series of
compounds.
COC2H5
H5C6
N
C
H3
CH3
CH3

19. • Insertion of m-hydroxyl group in one of the
phenyl ring of methadone causes decrease in
analgesic activity.
• Methadone series compounds are more
potent analgesic.
• Replacement of COC2H5 by H will decrease
the activity.
• Removal of any 2 phenyl grp. Decreases the
activity

20. PROPOXYPHEN HCl
COOC2H5
H5C6H2C
N
C
H3
CH3
CH3

21. MORPHINANS
• LEVORPHENOL TARTARATE
• Morphinans are made by removing E ring of morphine, the
4,5- ether bridge.
• LEVORPHENOL TARTARATE is 7.5 times more potent than
morphine.
• Loss of 4,5 epoxide and 7,8 double bond allows greater
flexibility and leads to increased binding affinity at all opioid
receptor subtypes compared with morphine.
O
H
N
CH3

22. BENZOMORPHANS
• Structural modification of morphine ring by removing
C ring of morphinan structure gives benzomorphans.
• Eg. PENTAZOCINE
• It is mixed agonist/antagonist displaying differing
intrinsic activity at opioid receptors.
• At μ receptor-partial agonist and weak antagonist
O
H
N
C
H3
CH3
CH3
CH3

23. NARCOTIC ANTAGONIST
• Blocks effects of narcotics
• Used in the treatment of overdose of narcotic.
• Structurally related to morphine
• Except group attached to nitrogen
• They prevent excessive respiratory depression
caused by administration of morphine

24. NALORPHINE HCl
• Mixed opioid agonist-antagonist
• Mu-antagonist, Kappa-agonist
• Uses- treat narcotic induced respiratory
depression, treat overdose of morphine,
methadone, levorphanol
O
H
N
O
OH
CH2
.HCl

25. LEVALLORPHAN TARTARATE
• Antagonises opioid effect by competing for
the same receptor site.
• Binds to mu receptor.
• Uses- complete or partial reversal of narcotic
depression, respiratory depression due to
opioids.
O
H
N
O
CH2
O
H
OH
O
O
OH
O
H
.

26. NALOXONE HCl
• Antagonizes opioid effects by competing for same
receptor sites (mu)
• Uses- complete or partial reversal of narcotic
depression, including respiratory depression induced
by narcotics, propoxyphen, methadone. Used in
treatment of narcotic overdose.
O
H
N
O
CH2
O
.HCl