Pharmacology - Analgesics Morphine

1. One of the most frequently asked questions concerns mixedagonist-anatagonists (MAA) – they ask you to identify which drugs out of a list of 5 is an MAA. The one they usually expect you to know is pentazocine, but sometimes nalbuphine. Since these drugs have proved to be not very popular with patients, they have fallen out of use, so I would imagine that they don’t ask so many questions on these drugs anymore.
2. Additional drug identifications they always ask involve knowing that naloxone is an antagonist used to treat overdose, and that methadone is used in detoxification of morphine addicts.
3. Some questions give you a list of pharmacological effects and ask you to identify which is not an effect of morphine. Morphine produces respiratory depression, euphoria, sedation, dysphoria, analgesia, and constipation and urinary retention. The substitution they often make is diarrhea for constipation, or perhaps diuresis for urinary retention.
4. The last most frequently asked type of question regarding opiates concerns overdose of toxicity. In overdose morphine causes coma, miosis, and respiratory depression. Sometimes they ask the mechanism of respiratory depression: loss of sensitivity of the medullary respiratory center to carbon dioxide.