SHORT NOTE: DHATURA POISONING

The Plant

• Commonly grows in waste places all over India; also called Thorn Apple or Jimsonweed
• Two varieties: Datura alba (Safed dhatura - white flowers) and Datura niger (Kala dhatura - black/purple flowers)
• Datura stramonium grows in the Himalayas; also D. atrox and D. metal
• Fruits are spherical with sharp spines; contain yellowish-brown seeds resembling chilli seeds
• One average fruit contains 450-500 seeds; 100 seeds weigh ~1 gram
• All parts are poisonous, but seeds and fruits are most toxic

Active Principles (Alkaloids)

1. Laevo-hyoscyamine (primary active alkaloid)
2. Hyoscine (Scopolamine)
3. Traces of Atropine (considered a racemic form of hyoscyamine formed during extraction)

• These alkaloids are anticholinergic in mechanism

Mechanism of Action

• Stimulate the higher centres of the brain and motor centres (initially)
• Inhibit secretions of sweat and saliva
• Dilate cutaneous blood vessels and the pupil
• Stimulate the heat-regulating centre in the floor of the 3rd ventricle
• Initial stimulation is followed by depression and paralysis of vital centres in the medulla

Signs and Symptoms

Classic Mnemonic - "5 Similes":

The 9 D's (Parikh's) / 10 D's (Dikshit's):

1. Dryness of mouth & throat
2. Difficulty in talking (dysarthria)
3. Dysphagia
4. Dilatation of cutaneous blood vessels
5. Dilatation of pupils
6. Dry hot skin
7. Drunken gait (staggering, incoordination)
8. Delirium (restless, purposeless; picks at clothing; tries to pull imaginary threads from fingertips; thread imaginary needles - pin-rolling movements)
9. Drowsiness
10. Dysuria (Dikshit adds)

Additional features:

• Earliest symptom: bitter taste in the mouth
• Headache, giddiness
• Vomiting (due to gastric irritation from crushed seeds)
• Visual and auditory hallucinations; dreadful delusions
• Scarlatiniform rash (exfoliation of skin over body)
• Pulse: initially full and bounding → later weak, irregular, intermittent
• Respiration: increased
• Increased muscle tone and deep reflexes; muscular spasms
• The patient does not remember anything about the illness when they recover
• Conjunctiva - red and injected

Course:

• Excitement/delirium phase lasts 1-2 hours → passes off into deep coma/sleep
• Patient may stay ill for 2-3 days; definite improvement in 24 hours
• On recovery: secondary delirium may appear as stupor passes

Fatal Dose & Fatal Period

Treatment

1. Stomach wash - with weak KMnO4 solution or 4-5% tannic acid
2. Emetics (if early)
3. Enema with sodium sulphate (purgative)
4. Physiological antidotes:
   • Physostigmine 0.5-1 mg IV/IM every 1-2 hours - preferred (crosses BBB, relieves both cerebral and peripheral manifestations)
   • Neostigmine (Prostigmine) 0.5-1 mg SC or 2.5 mg IV every 3 hours - more effective and less toxic; no central action
   • Pilocarpine nitrate 5 mg SC - no central action
5. Purgatives - beneficial
6. Short-acting barbiturates for convulsions
7. Sponging to relieve hyperpyrexia
8. Artificial respiration and oxygen inhalation
9. Monitoring - moistening of tongue and pupil size returning toward normal are valuable guides to treatment
10. Morphine - physiological antidote but contraindicated (toxic combined effect)

In non-fatal cases, recovery takes 1-2 days; the pupillary effect is the last to disappear.

Postmortem Appearances

• Signs of asphyxia (non-characteristic)
• Dhatura seeds or their fragments found in stomach/intestines
• Stomach shows slight inflammation / congestion of GIT
• Lungs are congested and oedematous
• All organs congested
• Dhatura seeds resist putrefaction and may be found even in decomposed bodies (though the mydriatic principle within seeds is destroyed by putrefaction; can be chemically detected after a long time)

Medicolegal Aspects

1. Criminal use - used mainly to stupefy victims for robbery, kidnapping, rape, and theft ("road poison" / "traveller's poison")
   • Seeds mixed with food, tea, drinks, paan (betel leaf), sweets, rice, dal, coffee
   • Seeds/leaves mixed with tobacco or ganja and smoked in chillum (pipe)
   • Decoction added to liquor to enhance intoxication
   • Fumes from burning seeds mixed with resin
2. Accidental poisoning - children eating raw fruits; seeds mistaken for capsicum seeds; used as aphrodisiac; juice used to treat rheumatism; used by Vaids and Hakims
3. Homicidal use - occasionally (historical case from 1921)
4. Active principle excreted unchanged in urine for 10-12 hours after administration - urine should be preserved for analysis
5. If victim reaches a police station, may be mistaken for a drunkard (drunken gait + difficulty in talking)
6. Warning boards are put up at railways and pilgrim places advising travelers not to accept food or 'prasad' from strangers
7. Dhatura is classified as a deliriant poison (along with Cannabis and Belladonna)
8. Can be confused with: drunkenness, heat stroke, mental disease, head injury, hypoglycemia, carbon monoxide poisoning

• Parikh's Textbook of Medical Jurisprudence, Forensic Medicine and Toxicology, Chapter 54 (DHATURA section)
• PC Dikshit's Textbook of Forensic Medicine and Toxicology, Deliriant Poisons - Datura Fastuosa section