Strychnine is a bitter alkaloid drug derived from the seeds of the Strychnos nux-vomica tree, native to Sri Lanka, Australia, and India. It has been used as a rodenticide for centuries (e.g., rat poison, gopher poison, etc.), though it can kill almost any animal. It does not usually appear to be toxic to plants. Strychnine breaks down fairly quickly in soil, is unlikely to contaminate water, and does not evaporate, but it can be inhaled as dust, and accidental fires involving strychnine bait may produce toxic fumes. It can also cause a toxic reaction when absorbed through the skin, and is a dangerous convulsive poison when ingested.
There is no evidence that chronic strychnine exposure causes cancer, mutations, reproductive disorders, or developmental abnormalities, but its immediate effects are often severe. Symptoms of strychnine poisoning begin 15 to 30 minutes after ingestion. There may be an initial violent convulsion, but frequently symptoms begin with restlessness, apprehension, heightened perception (hearing, vision, etc.), abrupt movements, exaggerated reflexes, muscular stiffness of face and legs, and, rarely, vomiting. There may be one to ten such attacks before recovery or death from respiratory arrest (suffocation). The fatal dose is usually in the range of 100-200 mg, but as little as 30 mg in adults and 15 mg in children has proved fatal.
If working with strychnine-based pesticide: avoid contact with eyes, skin, or clothing. Avoid breathing dust. Do not rub eyes or mouth with hands. If you feel sick in any way, stop work and get help right away. Wear rubber gloves, long-sleeved protective clothing, and a dust respirator type mask. Wash your skin, clothes, and gear thoroughly with soap and water after working, and before eating, smoking, or drinking anything. If strychnine is swallowed, have the victim drink 1-2 glasses of water, and induce vomiting. If strychnine is inhaled, remove victim to fresh air and begin artificial respiration if necessary.
When storing strychnine, always keep it locked, out of the reach of children and pets, and sealed properly so that it does not contaminate other substances such as fertilizers or food.
In smaller doses, strychnine is used in homeopathic medicines (labeled "nux vomica") and as a stimulant in veterinary medicine.
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