Made from a mixture of baking soda and powder cocaine, crack is a version of cocaine—but at a lower purity level. The key difference is that crack is smoked. This method of ingestion allows the drug to seep into lung tissues, producing a completely different result. Smoking crack causes the high to be much faster and more intense than the high traditionally felt from powder cocaine. Crack’s high is extremely short, usually less than 15 minutes, causing the user to crave a frightening amount of the drug. Withdrawal symptoms can cause immense depression, agitation and insomnia – all of which drive an addict to keep using the drug.11
Physical dependence on a drug can cause serious withdrawal symptoms if a person suddenly stops using the substance or severely reduces the dose. The withdrawal process itself can be uncomfortable and dangerous. Some of the classic signs of withdrawal include tremors, cold sweats, involuntary movements (e.g., jerking, twitching, or shaking), nausea and vomiting, muscle cramps and bone pain. Because withdrawal can be dangerous, proper medical detox can be a life-saving step in recovery. The Twelve Step programme for Beginners

To feel good. Drugs can produce intense feelings of pleasure. This initial euphoria is followed by other effects, which differ with the type of drug used. For example, with stimulants such as cocaine, the high is followed by feelings of power, self-confidence, and increased energy. In contrast, the euphoria caused by opioids such as heroin is followed by feelings of relaxation and satisfaction.
An average of about three months of residential treatment seems to be effective. The optimal treatment time seems to be similar in non-residential treatment, suggesting a combination of residential and non-residential treatment might be effective over that time. But completing the treatment program and actively participating seem to be more important than treatment setting or length.
Research the history of the Treatment Center or facility.  What is their success rate?  Can you find any medical recommendations for them online from members of the established rehab or medical community?  How long has the Center been in operation?  Is their leadership on solid ground?  Are there any signs of financial corruption associated with the Center that is readily visible on the Internet?  It is your responsibility to dig for this information.  If you cannot find any information about a given Treatment Center online or at your local library, move on to the next Center on your list! 3 Stages of Drug Alcohol Rehab-How It Works