The document discusses various opioid analgesics including codeine, tramadol, pethidine, methadone, and opioid antagonists such as naloxone and naltrexone. Specifically, it provides information on their mechanisms of action, indications, dosages, durations of action, and pharmacological properties. It compares the potency and toxicity profiles of different opioids relative to morphine.

1. OTHER
OPIOID
ANALGESICS

2. It is a methyl ester of morphine and
less potent than analgesic than
morphine.
It is widely used as antitussive agents.
Codeine depresses the cough center
even in small doses.
Codeine use has lesser chances of
addiction and tolerance is uncommon.

3.  Itabsorbs well when given orally
compared to morphine.
 Duration of action is 4-6 hrs.
 Antitussive dosage is 10 – 30 mg.
 Codeine is also available in
combination with paracetamal for
analgesia. (CODPLUS: Codeine
30 mg + Paracetamol 500 mg)

4.  Is a recently developed synthetic codeine
analog.
 It acts via opioid receptors in CNS to
produce analgesia.
 It also inhibits the reuptake of nor
adrenaline and serotonin.
 It is indicated to moderate, severe, chronic
pain and in painful diagnostic procedures
and in surgery.

5.  It is also known as Meperidine.
 Pethidine is 1/10th as potent as
morphine. (100 mg of pethidine
= 10 mg of morphine).
 Onset of action is more rapid
and duration of action is very
short.
 It produces corneal anesthesia.

6.  Onset of action begins after 15
minutes when ingested orally.
 Absorption is erratic after IM
injection.
 Pethidine crosses placental barrier.
 Pethidine toxixity differs from
morphine toxicity, it produces CNS
excitation, which is characterized
by tremors, muscle twitches and
seizures.

7.  A synthetic opioid, has actions similar to
morphine. Its outstanding features are
2. Effective analgesic
3. Effective by oral route
4. Its long duration of action effectively
suppresses withdrawal symptoms in opioid
addicts.
5. Used as substitution therapy for treating
opioid dependence.

8. 1 mg oral methadone are
given for every 4 mg
morphine.
Its pharmacology are similar
to that of morphine.
Used as an anesthetic agent
and for treating opioid
dependence.

9.  An opioid antagonist is an receptor
antagonist that acts on opioid
receptors.
 Commonly used opioid agonist are
III.Naloxone
IV.Naltrexone
V.Pentazocine

10.  Naloxone is a structural analog for
morphine.
 It have high affinity to mu receptor and low
affinity towatds delta and kappa sites.
 Naloxone is a drug of choice for treating
morphine overdose.
 Used in reversing neonatal asphyxia due to
opioid use in labour ward.

11.  It is a pure antagonist and chemically
related to Naloxone.
 It is more potent than Naloxone due to its
longer duration of action.
 Used as a maintainence drug in morphine
over dosage.
 Effective when administered orally.
 Alcohol craving is also reduced by
Naltrexone.