addiction

Over dependence on, and compulsive craving for, a drug (habit forming stimulating or narcotic substance) such as alcohol, cannabis, nicotine, or a derivative of cocoa or poppy. During addiction, discontinuation of the drug causes specific reactions (called withdrawal symptoms) such as sweating, vomiting, and tremors which cease when the use is resumed. Classified as a chronic and progressive disease, it requires prolonged professional care for mitigation and remediation. Because in popular usage any excessive craving (such as for chocolate or junk foods) is termed an addiction, WHO recommends the use of the term drug dependence when referring to drug addiction.