Crack and cocaine have three similar effects on the human body. Although crack is heat resistant and cocaine is destroyed by heat, both cause hypertension. Also, crack and cocaine bring about physiological and psychological damage, depending on pre-existing conditions and the extent of drug use. For example, hallucination, psychosis, paranoia and aggressive behavior may occur, and an overdose of either may cause cardiac collapse or convulsion. Finally, use of both drugs can lead to addiction.