Modafinil is classified as a Schedule IV controlled substance, meaning that it cannot be legally obtained without a prescription from a physician. According to the United States Drug Enforcement Agency, the drugs classified in this category are believed to have a very low potential for abuse or physical dependence (addiction). Nonetheless, there does appear to be some research to suggest that modafinil might have a potential for addiction or abuse:
- A 2009 neuroimaging study presented in the Journal of the American Medical Association reported that modafinil blocked the reuptake of the neurotransmitter dopamine in neurons in an area of the brain known as the nucleus accumbens. The nucleus accumbens is often wrongly referred to as the “pleasure system/center of the brain” or other similar label; however, it is an important area in the experience of being rewarded that is associated with repeating a particular behavior. This observed action of modafinil is similar to the action of very addictive drugs, such as cocaine, and the researchers suggested that modafinil may have an addictive potential in people who are vulnerable for drug dependence.
- Research has indicated that there is low-level tolerance developed with modafinil use, but the research is mixed regarding withdrawal effects associated with its discontinuation. If there are any physical withdrawal effects associated with modafinil, they are most likely mild; however, the development of even mild tolerance suggests that some people may abuse the drug in order get the same affect that once occurred at lower doses, and this might lead to psychological feelings of dependence. There is a case report where this very issue occurred in an individual who used very high doses of modafinil for daytime sleepiness. Nonetheless, true physical dependence from modafinil use or abuse is most likely very rare.
- As discussed below, modafinil use is becoming popular with students due to its concentration-enhancing abilities. This type of use may lead to more reports of people who take modafinil being diagnosed with substance use disorders as a result of very chronic modafinil use.