What causes fainting and how to prevent it during needle procedures
Fainting, or syncope is a temporary loss of consciousness when the brain doesn’t get enough oxygen. Many things, including dehydration, low blood sugar, or anxiety, can cause it. As all doctors know, a common trigger for fainting is seeing blood or a needle.
Emotional fainting is very common in humans, especially in younger people, but it is extremely rare in non-human vertebrates. Fainting may be a response that Homo sapiens …