649 



N(coiir;e Cecence'^ce 181 



Associated features. Users or inhalants nearly alwavs use other psvchoactive sub- 

 stances as .veil. When inhaiant Dependence exists, hosvever. it is usuailv clear that 

 inhalants are the prererred substance, and inhalants are used regulariv whereas other 

 substances are used oniv sporadicallv. E-. en occasional users or mhaiants are iikeiv to 

 have sier.iricant ph\sical and mental problems. 



Course. Younger children diagnosea as having Inhaiant Dependence mav use 

 inhalants several times a wee!<. orten on weekends and arter school. Severe depen- 

 dence in '.oung adults mav involve varvine periods or intoxication throughout each dav 

 and occasional periods of heavier use that mav last several davs. This pattern mav 

 persist tor manv vears. with recurrent need ror treatment. Users of inhalants mav have a 

 prererrec level or degree or intoxication, and the method of administration allows a 

 user to m.aintain that specific level for several hours. Chronic heavv users or inhalants 

 mav deve'op renal and hepatic complications. 



Tole'ance to inhalants has been repored. but mav be mereiv increased use over 

 tim.e. witr. more pe'iods of intoxication and increased preterence for higner levels oi 

 intoxication. Withcrawal has aiso been reported, but there is inadequate evidence to 

 substantiate its existence. 



Prevalence. No information. 



305.10 Nicotine Dependence 



See Nicotine-Induced Organic viental Disorders ip. 1 3C) for a description of Nicotine 

 Withdrawal. 



Patterns of use. .^t present, the most common form of Nicotine Dependence is 

 associatea with the inhalation ot cigarette smoke. Pipe- and cigar-smoking, the use of 

 snuff, anc the chewing of tobacco are less likelv to lead to Nicotine Dependence. The 

 more rapid onset of nicotine effects with cigarette-smoking -leads to a more intensive 

 habit pattern that is more dift'icult to give ud because of the frequencv of reinforcement 

 and the greater phvsicai dependence on nicotine. 



Associated features. People with this disorder are often distressed because of their 



inability to stop nicotine use, particularly when they have serious phvsicai svmptoms 

 that are aggravated bv nicotine. Some peoole who have Nicotine Dependence mav 

 have difficulty remaining in social or occupational situations in which smoking is pro- 

 hibited. 



Course. The course of Nicotine Dependence is variable. .Most people repeatedly 

 attempt ro give up nicotine use without success. In some the dependence is brier, ir. 

 that when thev experience concern about nicotine use. they promptly make an erfort 

 to stop smoking and are successful, though in many cases they may experience a 

 period of Nicotine Withdrawal lasting from days to weeks. Studies of treatment out- 

 come suggest that the relapse rate is greater than 50% in the first 6 months, and at least 

 70''.'b within the first 12 months. After a vears abstinence, subsequent relapse is un- 

 likely. 



The difficulty in giving up nicotine use definitively, particularly cigarettes, mav be 

 due to the unpleasant nature of the withdrawal syndrome, the deeplv engrained nature 

 of the habit, the repeated en'ects of nicotine, which rapidly follow the inhalation of 

 cigarette smoke (75,000 puffs per vear for a pack-a-dav smoker), and the likelihood that 

 a desire to use nicotine is elicited by environmental cues, such as the ubiquitous 



