Toxicology

Strychnine Poisoning

Strychnos Nux Vomica�(Kuchila)

• Grows in Manbhum, Gorakhpur, & coastal region of Malabar, Madras, Coromandal in India
• Its ripe fruit contains a seed that has strychnine as the active principle and is poisonous
• Seed
• Flat, circular, disc having concave surface on one side and convex face on the other side
• 7/8” to 1” in diameter and ¼” thick
• Ashy gray in colour has a shining surface with short satiny hairs.
• It has a bitter taste
• Active principles are alkaloids Strychnine & Brucine(1/10^th poisonous but action similar

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Nux Vomica Seed

• Bark, wood and leaves contain Brucine only
• Species of Plant containing strychnine
• Strychnos colubrina also called snake wood and Kuchila Lata
• Strychnos ignatii also called St. Ignatius Beans
• Strychnos tieute also called Upastree
• Tribal use of seeds
• Tribals of Malay Peninsula used the seeds in making arrow poison

Clinical Picture

• Symptoms- Paroxysmal spasms of muscles
• Appear immediately or within 5-10 mts of intake
• Rarely delayed for an hour or more
• Intensely bitter taste
• Choking sensation in throat
• Stiffness of neck and face
• Twitching of muscles start, at first clonic convulsions then tonic develop
• Gradually interval between two paroxysms shortens and duration of paroxysm increases

Features of Convulsions

• Muscles relax completely between spasms
• Mind remains clear till death
• Risus sardonicus- Before the spasm begins
• A sad smile like spasm of facial muscles
• Opisthotonos
• Backward arching of body
• Emprosthotonos
• Spasmodic forward bending of body
• Pleurosthotonos
• Spasmodic sideways bending of body

Strychnine poisoning

• Death due to asphyxia (diaphragm contracted) or by exhaustion
• Treatment
• Control convulsions
• Muscle relaxants or general anaesthesia may be required
• Artificial respiration & Oxygen
• Gastric lavage with Pot. permanganate

Difference between strychnine poisoning and tetanus

• Strychnine
• No history of injury
• Onset sudden
• All muscles affected together

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• During interval muscles completely relaxed
• Death takes place within a few hours. If death not within 4-6 hrs then chances of recovery great

• Tetanus
• History of injury
• Onset gradual
• Muscles of neck & lower jaw(Lockjaw) affected first
• During intervals muscles are rigid
• Death rarely within 24 hrs. Delayed for several days

Strychnine poisoning

• Fatal dose
• 1 seed = 2gm = 20 mg strychnine(3-5 seeds = death)
• 60 to 100 mg of pure strychnine
• Smallest-15 mg
• Fatal period
• Average- 1 to 2 hrs
• Earliest- 5 to 30 mts
• Delayed up to 6 to 18 hrs

P.M. Finding

• Rigor mortis sets in early and lasts longer
• In some cases tetanic spasm may pass in to cadaveric rigidity without the initial stage of relaxation
• Livid patches may be present on body which may be mistaken for bruises
• Mucous membrane of stomach and duodenum may show patches of ecchymosis or congestion

P.M. Finding(Cont.)

• Heart is empty and contracted but Rt. Side may be full with dark fluid blood
• Lungs are congested
• Brain with meninges and upper part of spinal cord are congested

Medico-legal Points

• Strychnine is very stable and resists degradation due to putrefaction of the body
• May be detected even after years
• Accidental
• In mistake of some other drug
• Sediment of tonic in past have caused poisoning
• Suicidal- Rarely in India but cases reported
• Homicidal-Rare. Cases reported in England

Medico-legal(Cont.)

• Nux Vomica Seeds
• Sometimes used for suicidal or homicidal purposes
• Hakims & Vaidyas use as a drug and accidental poisoning has occurred
• Used as an aphrodisiac
• Also used as cattle poison
• Used for killing street dogs
• Detection of strychnine in viscera
• Does not necessarily mean poisoning
• Excretion is slow taking 3-8 days for disappearing from body after being taken as medicine
• 20% excreted unchanged
• The individual may be addicted to it

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