Cocaine craving and use during daily life.

Rationale: Craving is often assumed to cause ongoing drug use and relapse and is a major focus of addiction research. However, its relationship to drug use has not been adequately documented.

Objectives: The aim of this study was to investigate the relationship between craving and drug use in real time and in the daily living environments of drug users.

Methods: In a prospective, longitudinal, cohort design (ecological momentary assessment), 112 cocaine-abusing individuals in methadone maintenance treatment rated their craving and mood at random times (two to five times daily, prompted by electronic diaries) as they went about their everyday activities. They also initiated an electronic diary entry each time they used cocaine. Drug use was monitored by thrice-weekly urine testing.

Results: During periods of urine-verified cocaine use, ratings of cocaine craving increased across the day and were higher than during periods of urine-verified abstinence. During the 5 h prior to cocaine use, ratings of craving significantly increased. These patterns were not seen in ratings of heroin craving or mood (e.g., feeling happy or bored).

Conclusions: Cocaine craving is tightly coupled to cocaine use in users' normal environments. Our findings provide previously unavailable support for a relationship that has been seriously questioned in some theoretical accounts. We discuss what steps will be needed to determine whether craving causes use.