Drinking rubbing alcohol is extremely dangerous and should never be done. Rubbing alcohol usually contains isopropyl alcohol, which is toxic to humans if ingested. Even small amounts can cause serious health problems such as vomiting, diarrhea, abdominal pain, internal bleeding, dehydration, low blood pressure, shock, coma, and can be fatal. It affects the central nervous system and can cause intoxication similar to drinking alcohol but with far more severe toxic effects. Medical emergency attention is necessary if someone drinks rubbing alcohol, as it can cause severe poisoning and even death.