654 



Exhibit 5 



Women and 

 tobacco 



Nicotine dependence' 



Nicotine, an alkaloid, is a constituent of all tobacco products 

 and is fundamentally the reason why people use tobacco: nicotine- 

 free tobacco does not satisfy the needs of those w^o are dependent 

 on tobacco. 



Alkaloids are a group of chemical compounds of plant ori- 

 gin, many of which have long been used by people for their medi- 

 cinal properties, their psychoactive effects and as poisons. .Most 

 alkaloids are poisonous at high concentrations and nicotine is no 

 e.xception; at high exposure levels it is a potent and lethal poison. 



Alkaloids are by definition alkali-like and nicotine can e.xist 

 as :he free base or as a salt. W'hen tobacco is combined with lime 

 for chewmg. as in south-east Asia, the nicotine is released from 

 the tobacco as the free base, and absorbed in the mouth. Smoke 

 from pipes and cigars also contains nicotine as the free base which 

 is absorbed in the mouth and nose. The smoke from other 

 nicotine-delivery devices, particularly cigarettes, is acidic; in this 

 case, the nicotine is absorbed in the lungs. 



The absorption oi nicotine by the blood is very rapid; nico- 

 tine is quickly distributed to the brain and its effects on the central 

 nervous system are manifested almost instantaneously. 



Studies in both humans and animals have shown that nico- 

 tine is a potent psychoactive drug. High doses can lead to intoxica- 

 tion and death; at doses typically obtained from tobacco products, 

 nicotine is responsible for much of the pleasure and satisfaction 

 obtained by tobacco users. Through activation of mcotine recep- 

 tors in the central nervous system, nicotine can produce depen- 

 dence. It also appears that nicotine can alleviate various dysphoric 

 states associated with boredom, stress, and the nicotine withdrawal 

 syndrome. 



Nicotine administration can lead to tolerance and physiologi- 

 cal dependence. Tolerance is indicated by the diminished response 

 to repeated doses of nicotine. Nicotine-induced physiological de- 

 pendence and withdrawal are specific to the administration or 

 removal of nicotine itself. The withdrawal syndrome includes a 

 craving for nicotine, im.paired ability to concentrate, disrupted 

 cognitive performance, mood changes, and impaired brain func- 

 tion. The severity of the symptoms may be such that heavy smok- 

 ers are unable to abstain permanently from, tobacco without treat- 

 ment; however, the symptoms usually disappear within a few weeks. 



' This secTion is baied on information received from Dr J Hennin|lleld. Oief. Oiiucai Phar- 

 macology Branc.i. National Institute on Drug .\buse. .Addiaion Research Center. Baitimore. .MO, USA. 



33 



