|MadSci Network: General Biology|
Let's see what happens when we are drunk. Alcohol is metabolised very fast in our body into acetaldehyde and acetoacetic acid. During excess alcohol consumption, the levels of these compounds increases. Acetaldehyde being able to enter the brain, causes toxicity, and stimulates specific centres in the brain for vomiting. These centres are the Chemoreceptor Trigger Zone in the medulla and the vomiting centre in the brain stem. Concussion is a temporary loss of consciousness without severe damage to the brain in a head injury. The injury causes changes in the balance of ions in the fluid surrounding the brain. This imbalance again affects the two areas mentioned above, and there is vomiting. Vomiting usually follows after a short period of unconnsciousness. For the concussion part, I think it is best you consult some one more experienced like an emergency medical expert before actually believing my answer. This is based on what I have read and accordingly figured out.
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