Strychnine

Strychnine is a highly toxic (LD₅₀ = 0.16 mg/kg in rats, 1–2 mg/kg orally in humans), colorless crystalline terpene indole alkaloid belonging to the Strychnos family of Corynanthe alkaloids.

It is a neurotoxin. It primarily affects the motor nerves in the spinal cord which control muscle contraction. Strychnine is an antagonist of glycine. When the strychnine binds to this receptor, glycine is unable to bind to it at the same time and the inhibiting effect of glycine is reduced.  So I suppose one could view strychnine as a stimulant!  Without any inhibitory effect the motor neurons do not stop their stimulus and the victim will have constant muscle contractions.

Sources

The most common source is from the seeds of the Strychnos nux vomica tree, but it can be found in other plants of the genus Strychnos, family Loganiaceae.  The genus contains 196 various species and is distributed throughout the warm regions of Asia (58 species), America (64 species), and Africa (75 species). The seeds and bark of many plants in this genus contain the powerful poison strychnine.

The seeds of the species Strychnos nux-vomica are the chief commercial source of strychnine and were first imported to and marketed in Europe as a poison to kill rodents and small predators. Strychnos ignatii is a woody climbing shrub of the Philippines. The fruit of the plant, known as Saint Ignatius' bean, contains as many as 25 seeds embedded in the pulp. The seeds contain more strychnine than other commercial alkaloids. The properties of nux-vomica and Saint-Ignatius seeds are substantially those of the alkaloid strychnine.

Effects

Poisoning.  Strychnine can poison you whichever route is followed.  It is quickly absorbed via the gastrointestinal tract [mainly via the intestine], via  mucous membranes or via cuts and wounds.  It is transported by plasma and erythrocites, then leaves the bloodstream quickly and distributes to the tissues. Approximately 50% of the ingested dose can enter the tissues in 5 minutes.  In persons killed by strychnine, the highest concentrations are found in the blood, liver, kidney and stomach wall.

Strychnine competes with the inhibitory neurotransmitter glycine resulting in an excitatory state. However, the toxicokinetics after overdose have not been well described. In most severe cases of strychnine poisoning, the patient dies before reaching the hospital.

Strychnine poisoning can be fatal to both humans and animals. It produces some of the most dramatic and painful symptoms of any known toxic reaction. The following are the main features:

• A severe nausea is seen, which may include vomiting due to the bitter taste.
• Since the whole nervous system is excited, convulsions affect all the muscles. As time goes on, the intervals between the convulsions become shorter, and the convulsions last longer.  The face becomes cyanosed, with dilated pupils and prominent eye balls. The mouth may also froth. These symptoms are all due to spasms of the facial muscles.
• The body may be convulsed into all sorts of strange shapes. For example, the spasm of abdominal muscles may bend the body forward or the body may be flexed to one side.
• The person is conscious and the mind is clear until death.
• There is an immense reflex excitability. Even a small stimulus like light, noise or movement of the body may throw it into a spate of convulsions.
• Death usually occurs due to asphyxiation as respiration is affected by muscle spasm.

Any experiences will be near death or an actual death experience.

In medicine

You may find it extraordinary that a poison as potent as strychnine has medicinal uses, but it does.  As in all highly potent substances, the dose needed is truly tiny – homeopathic – in order for it to have any effect and it is on the list of homeopathic medicines for this reason.  It is also used in Chinese medicine.

One very obvious use is to treat low blood pressure. In the Indian Unani system of medicine, "Hudar" is a mixture containing Strychnos nux-vomica and used to elevate blood pressure. It does this by stimulating the heart. In theory it can also stimulate the digestive system.  The seeds are first immersed in water for 5 days, in milk for 2 days followed by their boiling in milk.  In India the quality/toxicity of traditional medical crude and processed strychnos seeds is usually controlled by examining the toxic alkaloids using established HPLC methods and/or HPLC-UV methods.

In low dosages, - because it acts as a stimulant, it has even been used by athletes to ‘enhance their performance’. Strychnine made headlines back in 1904 during the St. Louis Olympics. British athlete Thomas Hicks won the gold medal but not without a little help. About 10 miles from the finish line Hicks begged his trainers to let him stop running and give-up the race. His trainers refused and gave him a dose of strychnine as a stimulant to keep him going. It took four doctors to revive him so that he could leave the stadium.