Use, Abuse, and Addiction
Cannabis withdrawal in humans has long been described anecdotally and has now been codified by the medical community as a Cannabis Withdrawal Syndrome in the DSM-V. Both inpatient and outpatient studies contributed to the criteria for cannabis withdrawal in humans (Table 8.10). The most common symptoms associated with cannabis withdrawal are decreased appetite/weight loss, irritability, nervousness, anxiety, anger, aggression, restlessness, sleep disturbances, and depressed mood. A substantial percentage of heavy marijuana users (16%) exhibit withdrawal symptoms. Outpatient studies in adolescents and adults who sought treatment for cannabis dependence have shown that the majority of users reported histories of repeated marijuana withdrawal. The onset of withdrawal typically occurs within 1–3 days. Peak effects are experienced at 2–6 days, and most of the withdrawal symptoms last 4–14 days (Figure 8.11). The long onset of Δ9-THC withdrawal appears to be directly related to the long half-life and slow decline of blood Δ9-THC levels (Box 8.5).
FIGURE 8.10 Tolerance to the subjective and physiological effects of marijuana intoxication. (Left) Mean heart rate and subjective high after smoking one marijuana cigarette after 1, 5, and 9 weeks of smoking at least one 900 mg marijuana cigarette per day. (Right) Comparison of light-to-moderate smokers to heavy smokers in ratings of subjective high. These data show that repeated smoking of marijuana produces tolerance to the increases in heart rate and the subjective high produced by marijuana. Notice that tolerance is reflected by less of a peak response and a faster return to baseline for both heart rate and subjective high. [Taken with permission from Nowlan R, Cohen S. Tolerance to marijuana: heart rate and subjective “high.” Clinical Pharmacology and Therapeutics, 1977, (22), 550–556.]
Cannabis Withdrawal Syndrome in the Diagnostic and Statistical Manual of Mental Disorders, 5th Edition
From American Psychiatric Association. Diagnostic and Statistical Manual of Mental Disorders, 5th edition. American Psychiatric Publishing, Washington DC, 2013.
Some clinicians have argued for the existence of a protracted abstinence state, in which the body reconstitutes itself to a normal, predrug state that can be quite prolonged and may last up to 15–18 months. Mild flu-like symptoms may occur a week or more later. Other subjective effects of prolonged abstinence include cognitive deficits and sleep disturbances. During this recovery period, subjects report the recovery of behaviors as subtle as being able to better sustain concentration when doing visualizations or meditations within a treatment session, engaging in more difficult reading material, and being less accident prone.