Strychnine is a poison that is sometimes used in some pesticides. It has a powerful effect on the nervous system and disrupts certain signals from the nerves to muscles. This results in muscles throughout the body contracting involuntarily. Patients who are exposed to strychnine should get immediate medical attention to remove the toxin from the body and help prevent serious side effects.
Psychiatric
Many of the initial symptoms of exposure to strychnine affect the patient's emotional state, the Centers for Disease Control explains. Patients may initially feel agitated or have a sensation of extreme fear or apprehension. Other psychiatric symptoms relating to the nervous system include restlessness and being easily started. During the initial stages of strychnine poisoning, patients will be conscious and be aware of some of the other physical symptoms that they are experiencing.
Muscle Contractions
Strychnine primarily affects the central nervous system and results in the blockage of signals that signal for muscles to relax. This causes the muscles in the body to become rigid and persistently contracted. At first the symptoms cause muscles in the body to become rigid. Patients may feel pain in their muscles and may also experience stiffness in their jaw or in the neck. As the symptoms continue, patients will develop severe muscle convulsions, explains the University of Missouri-Columbia, which can occur within 15 to 20 minutes of exposure to the poison. These muscle spasms can be severe enough to damage the liver and the kidney, the CDC notes.
Risus Sardonicus
Strychnine exposure can lead to a group of symptoms that are known as risus sardonicus, the University of Edinburgh explains. This condition is the result of severe unopposed muscle contracting. One of the key symptoms of risus sardonicus is extreme contraction of the muscles in the back, which causes the body to bend fully backward, resulting in only the heels and the top of the head making contact with the ground. Risus sardonicus is also marked by a fixed grin appearing on the face of the patient, which is the result of involuntary muscle contractions in the face.
Respiratory Failure
Although initially the muscles necessary for respiration will still be able to function, eventually these muscles will become exhausted, which will prevent breathing. This results in total respiratory failure, which is fatal.
