Crack cocaine, a form of cocaine base, is derived from powder cocaine. Unlike the processing of freebase cocaine, converting powder cocaine into crack cocaine does not involve any flammable solvents. The powder cocaine is simply dissolved in a solution of sodium bicarbonate and water. The solution is boiled and a solid substance separates from the boiling mixture. This solid substance, crack, is removed and allowed to dry. The crack cocaine is then broken or cut into "rocks," each typically weighing from one-tenth to one-half of a gram. One gram of pure powder cocaine will convert to approximately 0.89 grams of crack cocaine. The DEA estimates that crack rocks are between 75% and 90% pure cocaine.

The effects of Crack are similar to those of Cocaine, although since Crack is smoked, additional risks exist. General effects include constricted blood vessels and increased temperature, heart rate, and blood pressure, restlessness, irritability, anxiety, and with long term use, violence and paranoia are noted. Additional risks of smoking crack include respiratory problems such as shortness of breath, chest pains, lung trauma and bleeding. As with cocaine, crack is highly addictive. Evidence shows that when cocaine and crack are smoked (as opposed to other methods), there is increased risk of compulsive cocaine-seeking behavior.