What is Strychnine Toxicity?
Strychnine is a substance that has been used for many centuries as a treatment for various health problems. These days, however, it’s quite rare for people to be poisoned by strychnine, although it does still happen occasionally in the United States. Strychnine impacts a certain type of receptors in the spinal cord that normally respond to a chemical called glycine. When these receptors are blocked by strychnine, it causes unexpected and painful contractions of the muscles.
People poisoned by strychnine often experience episodes of muscle contractions that feel like seizures but they stay fully awake and aware during these painful episodes. There are no effects or confusion after these seizure-like episodes, like you might see with normal seizures. These unique seizures with no after-effects are treated mainly by giving the person medications called benzodiazepines and by managing the problems caused by the excessive muscle contractions. Thankfully, most people who get through the initial poisoning don’t suffer any long-term or ongoing health problems from the strychnine.
What Causes Strychnine Toxicity?
Strychnine poisoning usually happens when someone accidentally or deliberately consumes substances that contain this chemical. While there are cases wherein strychnine is ingested on purpose, such as situations involving suicide or murder, there are also instances where this poisoning happens without intention. For example, this poisoning can occur through the consumption of specific Chinese or Cambodian herbal remedies like Miqianzi and slang nut.
Strychnine usually takes the form of a white powder, and is typically consumed orally. However, there have been instances of people injecting it into their veins or snorting it. This has been especially noted in cases where drugs like heroin and cocaine were laced or contaminated with strychnine.
Risk Factors and Frequency for Strychnine Toxicity
Strychnine is a toxic substance derived from the seeds of the Strychnos nux-vomica plant, found mainly in India, Northern Australia, and the East Indies. The plant has several names including “slang nut” or “slang Thai nut” in Cambodia and Thailand, and it appears in a number of Southeast Asian herbal remedies.
In the United States, strychnine has been used for various purposes including poisons and performance-enhancing drugs. Believe it or not, the 1904 Olympic marathon winner even took strychnine during the race, and more recently in 2016, an Olympic weightlifter tested positive for it.
However, after numerous cases of poisonings and fatalities linked to strychnine, its use has been significantly reduced in the U.S. over the past century. Back in the 1930s, it was a common cause of lethal poisonings in children, and up until the 1980s, strychnine could still be found in everyday products like digestive aids, sedatives, and cold remedies. However, the U.S. Food and Drug Administration ordered its removal from food and medicines in 1962. And by 1989, it was even banned as an indoor pesticide, though it can still be found in some outdoor poisons.
According to a report by the American Association of Poison Control Centers, in 2015 there were 72 instances of exposure to strychnine and one death.
Signs and Symptoms of Strychnine Toxicity
When assessing a patient’s health history, doctors should ask about substances they’ve ingested within the last few hours. This includes any herbal remedies that may hint at possible strychnine poisoning. It’s also important to know whether the patient has recently used cocaine or heroin. Strychnine is often used as a filler in these illicit drugs. Figuring out when the patient was exposed to these substances can also aid doctors in deciding whether stomach cleaning might be beneficial.
The physical examination usually kicks off with checking the patient’s airway, breathing, and circulation — basic elements of any emergency medical evaluation. Evaluators should also measure the patient’s body temperature as an increased temperature could be a sign of hyperthermia caused by intense muscle contractions. If a patient shows signs of difficulty in breathing, their airway may need to be secured. Uncontrolled acid levels in the body because of muscle contractions can lead to paralysis. And, when the breathing muscles get paralyzed, it’s often a major cause of death.
Testing for Strychnine Toxicity
A test known as thin layer chromatography can be done on samples collected from your stomach or urine to check for strychnine poisoning, a type of serious poisoning that can occur if you swallow, inhale, or come into contact with strychnine. Despite what you might think, blood testing isn’t very reliable for strychnine poisoning because the poison doesn’t stay in the blood for very long after any type of exposure.
Doctors should also conduct other tests to monitor your body’s overall wellbeing. This includes something called a basic metabolic panel, which measures different chemicals in your blood and provides information about your body’s metabolism. An arterial or venous blood gas test, which measures the levels of certain gases in your blood, may also be performed. These gases can help indicate how well your lungs and kidneys are working. Additionally, other tests might be done such as lactate level and urinalysis to get a better idea of your overall health.
The main goal of these tests is to check for conditions like hyperkalemia (an excessively high amount of potassium in your blood), acidosis (high levels of acid in your blood), rhabdomyolysis (a condition where muscle tissue breaks down and releases a substance into the blood that can harm the kidneys), and renal failure (a condition where the kidneys stop working properly).
Treatment Options for Strychnine Toxicity
The primary treatment for poisoning involves providing supportive care, which might include helping the patient breathe using a tube inserted into their windpipe if necessary. If the patient has recently ingested the poison within a few hours, activated charcoal might be given to help absorb the poison, or gastric lavage—a stomach pump—is considered. Still, care must be taken as these procedures could potentially induce seizures.
To manage mild to moderate cases of shaking or muscle contractions, medicines like barbiturates or benzodiazepines can be provided. They help the patient relax and prevent uncontrollable shaking. If the shaking is severe, leading to high body temperature or acidic blood, the patient might need to be put on a ventilator and provided with medications that prevent muscle movement. The patient should also be given plenty of fluids intravenously—through an IV—to treat a condition called rhabdomyolysis, which happens when muscle tissues are damaged. However, a specific drug called succinylcholine, typically used to facilitate intubation, should be avoided because it might increase the potassium level in the blood.
Luckily, with minor to moderate exposures, the patient is likely to recover fully, with no lingering problems with the nervous system or muscles.
What else can Strychnine Toxicity be?
The following medical conditions or treatments may be encountered during medical consultations or treatments:
- Arthrogryposis
- Conversion Disorder
- Emergency Treatment of Rabies
- Encephalitis
- Hemorrhagic Stroke
- Mandible Dislocation
- MIDR
- Neuroleptic Malignant Syndrome
- Pediatric Aseptic Meningitis
- Tardive Dystonia
