Causes
By Mayo Clinic staffLike many psychological disorders, drug addiction and dependence depends on several things. Two main factors include:
- Environment. Environmental factors, including your family's beliefs and attitudes and exposure to a peer group that encourages drug use, seem to play a role in initial drug use.
- Genes. Once you've started using a drug, the development into addiction may be influenced by inherited traits.
Changing brain pathways
Physical addiction appears to occur when repeated use of a drug alters the way your brain feels pleasure. The addicting drug causes physical changes to some nerve cells (neurons) in your brain. Neurons use chemicals called neurotransmitters to communicate.
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- Weaver MF, et al. Overview of the recognition and management of the drug abuser. http://www.uptodate.com/home/index.html. Accessed June 28, 2011.
- Substance dependence. In: Diagnostic and Statistical Manual of Mental Disorders DSM-IV-TR. 4th ed. Arlington, Va.: American Psychiatric Association; 2000. http://www.psychiatryonline.com. Accessed July 11, 2011.
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