Vomiting is an expulsive reflex of the upper gastrointestinal tract with an act of expelling the contents inside.
This is a protective phenomenon in most cases yet sometimes can be a sign of some other severe disease or disorder.
This vomiting is seen in normal life in case any irritant substances are consumed.
But in case of disease, disorder, and injuries, especially to the head and spinal cord, are worth medical consideration.
Vomiting is induced by gastric-related factors, blood-related, and also brain-related factors.
Reasons for vomiting
The reasons for vomiting include mainly two disturbance i.e.
Gastric or gut irritation. This vomiting is due to local gut wall irritation but not CTZ stimulation. This occurs due to
1. Foods irritating to mucous
When one consumes irritating foods like mushrooms etc., then the gut tries to get rid of them by vomiting.
2. Vomiting after drinking
Alcohol is an irritant substance and when one consumes excess alcohol or for the first time, there is a chance of gastric irritation and leads to vomiting.
3. Poisoning vomiting
Poisons that are irritants to gut mucous can be irritating and leads to vomiting. They can also induce vomiting by acting on the brain vomiting center.
When one consumes heavy food and there is a lack of proper digestion, then in-digested food is sometimes vomited. This is seen in cases like jaundice patients on the consumption of fat/oil-rich foods.
Central nervous system irritation
There is a sensitive zone in the brain, namely the chemoreceptor trigger zone (CTZ ). When there are any inducing drugs or substances in the blood or cerebrospinal fluid or a heady or spinal injury, it leads to CTZ stimulation which leads to vomiting.
1. Disease-related vomiting
Like in fever, headaches, migraines, etc., there are chances of vomiting due to indigestion (in the gut) or due to CTZ stimulation.
2. Journey-related vomiting or Motion sickness
This is vomiting due to disturbance in the balance of the ear saccules. This balance is disturbed when one is in motion in a giant wheel or going in a car or vehicle over hilly turns etc. This is due to nervous system stimulation (para-sympathetic).
3. Vertigo-related vomiting/ Vomiting due to dizziness
These two or related to some uneasiness in the brain and show explainable symptoms with vomiting.
4. Head injury or spinal cord injury etc.
When there is a sudden fall leading to head or spinal injury, it leads to vomiting due to CTZ stimulation of the vomiting center.
5. Snakebites/ insect bites
When there is poison injected into blood by a snake or insect, it can cause nervous system disturbances leading to vomiting.
6. Poison consumption for suicide.
When poisons like pesticides are consumed, they induce vomiting by the trigger of CTZ.
7. Vomiting due to asphyxia or lack of oxygen.
Lack of oxygen for a prolonged period induces a type of brain injury and, in some cases, leads to fits (epilepsy) and vomiting also.
Some drugs, when taken for treatment of other diseases, can also cause vomiting.
Example diclofenac sodium during fever.