Drugs that can be abused have a powerful impact on the functioning of the brain. Each time you use the drug, your brain’s reward center becomes activated. The resulting sense of euphoria increases your desire for the drug, making you want to use drugs again and again. However, it is not just the drug itself that elicits this desire to use. Our brains create complex memories that bind together many aspects of the drug-using experience. Thus, you may find yourself startled to be hit with a powerful craving when you drive past the place where you used to buy from your dealer. Understanding your triggers and learning strategies to cope with cravings is an essential part of maintaining sobriety. Common factors that contribute to drug cravings include: 


Physical dependence on the drug. It takes time for the body to become physically dependent on the drug, but many long-term drug users experience develop dependence. There are two signs of drug dependence: withdrawal symptoms and tolerance. Withdrawal refers to the physical symptoms that occur when it has been a while since you last used. This might include insomnia, sweating, aches and pains, headaches, or irritability. Tolerance is the need to use more of the drug to get the same effect you used to. 


People who are physically dependent on drugs tend to struggle more with cravings. This is because their bodies have come to physically require the drug for normal functioning. Without it, the brain sends intense signals asking for more of the drug, which you experience as cravings. 


Being in the same environment in which you used to use. Specialized areas of your brain bind together information into complex memories. Thus, your brain does not just remember that using drugs feels good. It also remembers who, what, where, when, and how you used to use drugs. Being in a similar environment — for example, running into a friend with whom you used to snort cocaine — can reactivate these drug memories and trigger strong cravings. 


Experiencing periods of stress. For many people struggling with drug use, using the substance is a way to alleviate stress. Tough day at work? Getting high may make you feel better, at least temporarily. Thus, even after taking the first steps toward sobriety, your instinct may be to use drugs when you are stressed. The important thing is to recognize this tendency and replace drug use with more adaptive stress reduction techniques. This is a major focus of therapy at professional drug treatment centers. 


Feeling down or depressed. There is an overlap between the brain regions activated by drug use and those involved in depression. Feeling depressed may trigger your brain’s reward pathway, causing you to seek drugs. This is one reason that people struggling with depression often turn to drugs or alcohol to alleviate their symptoms. Managing depression and other co-occurring mental health problems during treatment will help you overcome powerful drug cravings. 


Social events. Although everyone experiences different triggers for drug use, social events are a common trigger. Many people use drugs socially, so going to a party or hanging out with friends may make you feel a strong urge to use. This is particularly harmful when you observe other people using the drug, which can trigger intense cravings. Managing your social calendar and decreasing contact with the people with whom you used to use drugs is a good way to counteract these triggers. 


National Institute on Drug Abuse. Coping with craving. A Cognitive-Behavioral Approach: Treating Cocaine Addiction. http://archives.drugabuse.gov/TXManuals/CBT/CBT8.html 

Cleck, J.N. & Blendy, J.A. (2008). Making a bad thing worse: adverse effects of stress on drug addiction. Journal of Clinical Investigation.http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2214707/