FM13.18 | Narcotics, Anaesthetics, Cardiotoxic Plants & Insulin — Summary & Reflection

KEY TAKEAWAYS

FM13.18 covers four distinct forensic categories:

• Narcotic analgesics (opioids): mu-receptor agonism → miosis + respiratory depression + coma. Antidote: naloxone (short acting — monitor for re-narcotisation). PM: pulmonary oedema ± injection marks. NDPS Act 1985 governs controlled narcotics.

• Cardiotoxic plants:
• Oleander/Cerbera odollam/digitalis: Na⁺/K⁺-ATPase inhibition → Ca²⁺ overload → ventricular arrhythmia + AV block. Antidote: Digoxin Fab antibodies.
• Aconite: persistent Na⁺ channel activation → burning/numbness → arrhythmia. No specific antidote.

• Insulin: exogenous overdose → severe hypoglycaemia → coma. Antidote: IV dextrose / IM glucagon. Forensic key: absent C-peptide + high insulin = exogenous administration (not endogenous).

• Anaesthetics/NMBs: succinylcholine forensic trap (rapid hydrolysis — may be undetectable PM); bupivacaine cardiac arrest (lipid rescue with Intralipid); rocuronium reversal with sugammadex.

All FM13.18 deaths share one forensic theme: they may appear natural without targeted investigation.

REFLECT

You are called to certify the death of a 58-year-old man who was found unresponsive at home by his wife. He has a known history of hypertension and type 2 diabetes. His wife says she found an empty insulin pen near the bed but insists he was 'fine last night at dinner'. The GP has signed a death certificate as 'ischaemic heart disease'. You suspect insulin homicide. What is your forensic duty at this point? What specimens must be collected before the body is released for cremation? And what are the legal thresholds of evidence you need to trigger a criminal investigation rather than accepting the natural cause of death certificate?