- A Heroin is understood pharmacologically to function merely as a relatively weak and mild over-the-counter painkiller for headaches, comparable in strength to common aspirin or paracetamol tablets sold without prescription
- B Heroin (diacetylmorphine) is a highly lipid-soluble opioid that rapidly crosses the blood-brain barrier, causing intense euphoria; highly addictive; overdose causes respiratory depression and death
- C Heroin is understood to possess essentially no meaningful addictive potential whatsoever, even among regular habitual users, allowing patients to stop using it at any time without withdrawal symptoms occurring
- D Heroin is classified pharmacologically as a powerful central nervous system stimulant rather than as a depressant drug, producing alertness and increased heart rate rather than sedation and slowed breathing
Correct answer: B. Heroin (diacetylmorphine) is a highly lipid-soluble opioid that rapidly crosses the blood-brain barrier, causing intense euphoria; highly addictive; overdose causes respiratory depression and death
Explanation: Heroin: semi-synthetic opioid from morphine, diacetylated for higher lipophilicity (crosses BBB 100x faster than morphine). Acts on mu-opioid receptors in brain. Causes: euphoria, analgesia, respiratory depression (overdose mechanism). Withdrawal: intense cravings, pain, vomiting, insomnia. Treatment: methadone/buprenorphine maintenance, naloxone (overdose reversal).
Concept context
Pathogens, infectious diseases, non-infectious diseases, drugs, cancer, and public health. High NEET importance.