Drug therapy is a form of treatment that involves the administration of drugs to treat or prevent diseases. It is used to treat a variety of illnesses, from psychiatric disorders to cancer. Drug addiction is a chronic condition characterized by compulsive or uncontrollable search and use of drugs despite harmful consequences and changes in the brain, which can be long-lasting. The main interventions available for substance use disorders include drug therapy, behavioral therapy, and participation in support groups.
Behavioral therapies are the most common form of intervention for people with substance use disorders, followed by medication use. Social support groups also provide long-term opportunities for people in recovery to stay focused on their commitment to living a sober life. Patients may use medications to help restore normal brain function and decrease cravings. Medications are available for the treatment of opioid addiction (heroin, prescription pain relievers), tobacco (nicotine), and alcohol.
Scientists are also developing drugs to treat addiction to stimulants (cocaine, methamphetamine) and cannabis (marijuana). People who take more than one medication need treatment for all the substances they use. Pharmacological stimulating and blocking actions are non-permanent effects that only occur when the drug is taken and activated in the body. For more serious mental illnesses, medication is the most appropriate and effective treatment; for example, schizophrenia should be treated with an antipsychotic drug and severe depressive illness with an antidepressant.
In the treatment of addiction, medications are used to reduce the intensity of withdrawal symptoms, reduce cravings for alcohol and other drugs, and reduce the likelihood of specific drug use or relapse by blocking their effect. Types of pharmacotherapy include antimetabolites, antimitotics, antitumor antibiotics, asparagine-specific enzymes, biosimilars, bisphosphonates, chemotherapy, DNA-damaging agents (antineoplastic) and alkylating agents. Mixed agonist-antagonists have a dual action; they both stimulate neurotransmitter receptors in the brain and block the activation of neurotransmitter receptors by a specific drug or classes of drugs. Scientific research since the mid-1970s shows that drug abuse treatment can help many drug offenders change their attitudes, beliefs and behaviors towards drug abuse; avoid relapses; and successfully exit a life of substance abuse and crime.
The Drug Enforcement Administration (DEA) classifies drugs into five distinct categories or programs depending on their acceptable medical use and potential for misuse.