Cocaine has a number of short-term effects, including the unpleasant withdrawal symptoms mentioned above. Cocaine users frequently report that coming down from the drug is difficult, leading them to take more to prolong the high and avoid withdrawal. This is one of the reasons cocaine is so rapidly addictive. Many users report depression immediately after taking the drug and for days after.
Because cocaine gives the user a sense of power and confidence, users frequently think of themselves as functioning far better than they are. It is dangerous to drive a car on cocaine, especially when combined with alcohol. Because of the stimulant effects of cocaine, users drink more than they are accustomed to without feeling the depressant effects of alcohol. Cocaine, however, wears off much more rapidly, leaving the user more intoxicated than he thought he was. This situation increases the chance of suffering the worst of alcohol's debilitating effects, including slowed respiration, vomiting, and loss of consciousness. Alcohol and cocaine also combine in the human liver manufacturing a third substance, cocaethylene, which, while intensifying cocaine's euphoric effects, also increases the strain on the heart and the risk of sudden death.
At high doses, users of cocaine can become:
As with other stimulants, cocaine raises blood pressure, heart rate, and respiration. This increases the chances of respiratory arrest or stroke. High or frequent doses have caused seizures, strokes or heart attacks in some people. In rare cases sudden death (from cardiac arrest or seizures following respiratory arrest) occurs on the first use of cocaine or unexpectedly thereafter. It is impossible to determine who might have such an immediately fatal reaction to cocaine.