Cannabis abuse: A destructive pattern of cannabis use, leading to significant social, occupational, or medical impairment.
Must have three (or more) of the following, occurring when the cannabis use was at its worst:
Cannabis tolerance: Either need for markedly increased amounts of cannabis to achieve intoxication, or markedly diminished effect with continued use of the same amount of cannabis.
Greater use of cannabis than intended: Cannabis was often taken in larger amounts or over a longer period than was intended
Unsuccessful efforts to cut down or control cannabis use: Persistent desire or unsuccessful efforts to cut down or control cannabis use
Great deal of time spent in using cannabis, or recovering from hangovers
Cannabis caused reduction in social, occupational or recreational activities: Important social, occupational, or recreational activities given up or reduced because of cannabis use
Continued using cannabis despite knowing it caused significant problems: Continued cannabis use is continued despite knowledge of having a persistent or recurrent physical or psychological problem that is likely to have been worsened by cannabis."
Alan J. Budney, PhD, Professor of Psychiatry and Researcher at the University of Arkansas Center for Addiction Research, stated in his Oct. 2001 article "Marijuana Abstinence Effects in Marijuana Smokers Maintained in Their Home Environment," published in the Archives of General Psychiatry:
"This study validated several specific effects of marijuana abstinence in heavy marijuana users, and showed they were reliable and clinically significant.
These withdrawal effects appear similar in type and magnitude to those observed in studies of nicotine withdrawal...
Craving for marijuana, decreased appetite, sleep difficulty, and weight loss reliably changed across the smoking and abstinence phases. Aggression, anger, irritability, restlessness, and strange dreams increased significantly during one abstinence phase, but not the other."
Jack E. Henningfield, PhD, Associate Professor of Behavioral Biology at Johns Hopkins University School of Medicine, and Neal L. Benowitz, MD, Chief of the Division of Clinical Pharmacology and Experimental Therapeutics at the University of California at San Francisco, in an Aug. 2, 1994 New York Times article titled "Is Nicotine Addictive? It Depends on Whose Criteria You Use," and Daniel M. Perrine, Phd, Associate Professor of Chemistry at Loyola College in Maryland, in his 1996 book The Chemistry of Mind-Altering Drugs: History, Pharmacology, and Cultural Context, ranked the addictiveness of six drugs, with 1 being the most addictive, as shown in the chart below:
The Institute of Medicine published in its Mar. 1999 report titled "Marijuana and Medicine: Assessing the Science Base":
"In summary, although few marijuana users develop dependence, some do. But they appear to be less likely to do so than users of other drugs (including alcohol and nicotine), and marijuana dependence appears to be less severe than dependence on other drugs...
Adolescents, especially troubled ones, and people with psychiatric disorders (including substance abuse) appear to be more likely than the general population to become dependent on marijuana...
Some controlled substances that are approved medications produce dependence after long-term use; this, however, is a normal part of patient management and does not generally present undue risk to the patient."
Colin Blakemore, PhD, Chair of the Department of Physiology at Oxford University, and Leslie Iversen, PhD, Professor of Pharmacology at Oxford University, wrote in their editorial "Cannabis, Why It Is Safe," published in The Times [United Kingdom] on Aug. 6, 2001:
"For some users, perhaps as many as 10 per cent, cannabis leads to psychological dependence, but there is scant evidence that it carries a risk of true addiction. Unlike cigarette smokers, most users do not take the drug on a daily basis, and usually abandon it in their twenties or thirties.
Unlike for nicotine, alcohol and hard drugs, there is no clearly defined withdrawal syndrome, the hallmark of true addiction, when use is stopped."
John Cloud, Staff Writer for Time magazine, stated in his Nov. 4, 2002 article "Is Pot Good For You?":
"Those who believe you can't become physically or psychologically dependent on marijuana are wrong. At least three recent studies have demonstrated that heavy pot smokers who quit can experience such withdrawal symptoms as anxiety, difficulty sleeping and stomach pain.
On the other hand, the risk of becoming dependent on marijuana is comparatively low. Just 9% of those who have used the drug develop dependence. By comparison, 15% of drinkers become dependent on alcohol, 23% of heroin users get hooked, and a third of tobacco smokers become slaves to cigarettes."