Strychnine
| Strychnine |
|---|
| Formula | C21H22N2O2 |
| LD50 | 1 mg/kg |
| Molecular mass | 334.41 g/mol |
| CAS number | 57-24-9 |
| SMILES | [H][C@]([C@@](C(C=CC=C7)
=C7N34)5[C@H]6N(CC5)C2)3
[C@@]1([H])[C@@H](C6)[C@]
2=CCO[C@H]1CC4=O |
 | chemical structure of strychnine |
|
Strychnine (
pronounced (British) or (U.S.)) is a very toxic (
LD50 = 1 mg/kg), colorless crystalline
alkaloid used as a
pesticide, particularly for killing small
vertebrates such as
rodents. Strychnine causes muscular convulsions and eventually
asphyxia or sheer exhaustion. The most common source is from the seeds of the
Strychnos nux-vomica tree. Strychnine is one of the most bitter substances in the world. Its taste is detectable in concentrations as low as 1
ppm.
Strychnine acts as a blocker or
antagonist at the inhibitory or strychnine-sensitive
glycine receptor (GlyR), a
ligand-gated
chloride channel in the
spinal cord and the
brain.
Strychnine poisoning can be fatal to humans, and can be introduced to the body by inhalation, swallowing or absorption through eyes or mouth. It produces some of the best-known, most dramatic, terrifying, and painful symptoms imaginable. For this reason, strychnine poisoning is often used in literature and film.
Ten to twenty minutes after exposure, the body's
muscles begin to spasm, starting with the head and neck. The spasms then spread to every muscle in the body, with nearly continuous convulsions, and get worse at the slightest stimulus. They progress, increasing in intensity and frequency until the backbone arches continually. Death comes from asphyxiation caused by paralysis of the
brain's breathing apparatus, or by exhaustion from the convulsions. At that time, the body "freezes," even in the middle of a convulsion.
Rigor mortis sets in immediately, with the eyes left wide open.
Treatment involves giving depressants, such as intravenous
diazepam, to control the convulsions, and giving an
activated charcoal infusion to drink, which serves to absorb any poison remaining within the digestive system. If the patient lives 24 hours, recovery is probable.
Strychnine poisoning in animals occurs usually from ingestion of baits designed for use against rodents (especially
gophers and
moles) and
coyotes. Rodents baits are commonly available over-the-counter, but coyote baits are illegal in the United States. However, since 1990 in the United States most baits containing strychnine have been replaced with
zinc phosphide baits.
The most common domestic animal to be affected is the
dog, either through accidental ingestion or intentional poisoning. An approximate lethal dose for a dog is 0.75
mg per
kg body weight.
For a 0.3% strychnine bait, five grams could be enough to kill a twenty kilogram dog.
The onset of symptoms is 10 to 120 minutes after ingestion.
[ Symptoms include seizures, a "sawhorse" stance, and opisthotonus (rigid extension of all four limbs). Death is usually secondary to respiratory paralysis. Treatment is by detoxification using activated charcoal, pentobarbital for the symptoms, and artificial respiration for apnea.There is a common but wrong urban legend that strychnine is added to drugs like LSD or that strychnine is present in the peyote cactus. The dose of LSD is so small that it could not be mixed with a toxic amount of strychnine, even if strychnine made up an entire blotter square. See: Strychnine in LSD? (Erowid)*In the 1904 Olympics, Thomas Hicks (USA) won the marathon at St. Louis and collapsed. It took hours to revive him; he had taken brandy mixed with strychnine to help him win his gold medal.]
*Strychnine is the title of a song by 60s garage rock band The Sonics (later covered by The Cramps), which includes the lines:
Some folks like the water
Some folks like the wine
I like the taste
Of straight Strychnine
