Substance dependence and the compulsive use of drugs go hand in hand and refer to the continued use of a non-medically indicated drugs and medication. The term of "substance", when discussed in the context of the compulsive use of drugs and substance dependence, often refers to drugs of abuse, toxins and medications. All these substances, as a rule, have the intoxicating effects expected by the users. These substances can have usually either stimulating or depressive effects on the human body.
Compulsive use of drugs or substance dependence can involve the following ten categories of substances: cannabis (including hashish and marijuana); nicotine (only substance dependence); cocaine (including the "crack"); inhalants (including components of glue and gasoline, paint thinners); alcohol, phencyclidine (including angel dust, PCP, ketamine); amphetamines (including the "crystal meth"); opioids (including heroin, morphine, codeine, oxycodone, methadone); hallucinogens (including mescaline, MDMA and LSD); hypnotic, sedative and anxiolytic substances.
There are seven criteria in the diagnosis of the substance dependence: withdrawal -- when the individual may experience unpleasant physiological, emotional and mental changes, when the drug-taking is ceased or the use of the substance as a method to relieve withdrawal symptoms; tolerance -- which is defined by a need for more amounts of substance to obtain the expected effect and by experiencing a less effect with an extended use of the same quantity of the substance; permanent desire and repeated efforts for stopping substance use -- the substance is used for a longer time or in greater amounts; reduced activities; a long time spent in providing or in using the substance; and unceasing substance use.
Symptoms of compulsive use of drugs include the following: substance use, frequently in hazardous situations -- for example the driving or the operating machinery; substance use after a failure at school, work or many home obligations; unceasing substance use despite frequent negative relationship and social consequences of drug use; substance use as a result of legal problems.
There are many debates about difference between substance dependence and compulsive use of drugs. Usually, substance dependence is characterized by behavioral and physiological symptoms of the substance use, but compulsive use of drugs is characterized by social resultants of substance use. Substance dependence is commonly known as addiction, and it's characterized by behavioral and physiological symptoms that are related to the substance use.
Usually, such symptoms include a need for more amounts of drug substance for maintaining expected effects. Frequently, substance abuse is diagnosed among the drug new-users and, often, in early symptom of the substance dependence. But, substance dependence may appear without the compulsive use of drugs, which also can persist for long time without the transition to the substance dependence.