The umbrella term "drug rehabilitation", also referred to as "drug rehab", is a complex of therapeutic measures and procedures (pharmaceutical, psychotherapeutic, medical, etc.) to help an individual get rid of his or her drug dependency, including psychological and physical types of dependency on various psychoactive agents, such as "street drugs" (amphetamine, crystal meth, heroin, cocaine, etc.), alcohol, prescription drugs, and so on. Various measures of drug rehabilitation are intended to enable the drug user to quit taking drugs and, therefore, to avoid numerous negative consequences and implications of substance abuse - legal, physical, physiological, social, and financial.

For successful drug rehabilitation, the applied therapeutic measures should address all sides of drug dependency, including its physical and physiological aspects. Physical dependency on drugs develops quickly, sometimes, already after the first attempt to try a substance, especially in case of hard synthetic drugs. With repeated use, the brain and the nervous system gradually adapt to the substance and start needing it on a regular basis. In some time, in order to achieve the desired narcotic "high" from taking alcohol, nicotine, cocaine, and other drugs, the user gradually requires more and more of the substance. Any attempt for the abrupt quitting of the agent of dependency leads to developing numerous symptoms of withdrawal, which can be very strong and even hardly tolerable and can last for a long time - for weeks or even months. Withdrawal symptoms can manifest as anxiety, depression, drug cravings, suicidal thoughts and even attempts, seizures, delirium tremens, hypertension, psychoses, and other highly unpleasant and potentially dangerous forms. Sudden withdrawal from taking some hard drugs and even prescription medication, such as beta blockers, antidepressants, corticosteroids and anticonvulsants, could be extremely harmful for both the body and the brain and could even lead to fatality. In view of all that, successful drug rehabilitation requires applying various therapeutic measures to cope with physical dependency on the agent, which are known under the term "drug detoxification", or "drug detox".

Psychological dependency on drugs sometimes is even harder to cope with. It is addressed in drug rehabilitation centers alongside with physical dependency. Generally, patients are encouraged to learn how to interact with their own world without applying to drugs and how to change their habits, a social circle, and sometimes their entire lifestyle to make it a drug-free environment. Some of the examples of successfully applied programs of both physiological and psychological drug rehab are a Twelve-step program in Alcoholic Anonymous and other support groups, in-patient and out-patient residential treatments, "sober houses", and various types of care centers. It has to be noted that the psychological aspect of drug rehabilitation is absolutely crucial if the person wants to quit using addictive substances for good.

Pharmaceutical therapy is an important part of drug rehabilitation treatments. Patients, who are "hooked" on drugs like morphine or heroin, get significant help by taking medication of the opioid group, such as methadone and the newer drug buprenorphine, which efficiently work to reduce physical dependency and restore the balance of opioid neurotransmitters in the nervous system of the user. They can be used successfully in both short-term and long-term types of treatment. Another promising medication, which is still in its experimental stage, is ibogaine. It is claimed that ibogaine can help in reducing both physiological and psychological aspects of drug dependency related to a whole range of addictive substances. One more class of pharmaceutical agents, which is efficiently applied to treat mild to moderate drug addictions, is antidepressants, especially those of the last generation. Traditional types of drug rehabilitation mostly favour counselling, which could be very effective to cope with psychological aspects of drug addiction.