Which of the following feature differentiates pethidine from morphine?: (A) Local anaesthetic action, (B) More analgesic action, (C) More respiratory depression, (D) Suppresses cough effectively
Answer is A. In contrast to morphine, pethidine has following features 1/10 analgesic potency More rapid onset of action Shoer duration of action Not an effective cough suppressant Lesser spasmodic action on smooth muscles Local anesthetic action Less histamine relief - safer in asthmatics Higher oral; parenteral activity ratio Atropinic effects - dry mouth, blood vision Miosis, constipation Urinary retention are less prominent.