Acetaminophen toxicity with tobacco

Q: Acetaminophen toxicity corelates in direct proportion with tobacco consumption (means higher the cigarettes per day higher the chances of toxicity)?

A) True

B) false

Answer: B

Although tobacco is an independent risk factor for acetaminophen toxicity, it has no direct correlation with the amount of tobacco or number of cigarettes per day. Even a small amount of tobacco consumption can increase acetaminophen toxicity. This is due to the fact that tobacco smoke contains CYP1A2 inducers which increases oxidative metabolism. 

A large number of smokers are simultaneously regular users of alcohol which further increases the risk of mortality.

#toxicology

References:

1. Dong SX, Ping ZZ, Xiao WZ, et al. Effect of active and passive cigarette smoking on CYP1A2-mediated phenacetin disposition in Chinese subjects. Ther Drug Monit 1998; 20:371.

2. Seo KW, Park M, Kim JG, et al. Effects of benzothiazole on the xenobiotic metabolizing enzymes and metabolism of acetaminophen. J Appl Toxicol 2000; 20:427.

3. Schmidt LE, Dalhoff K. The impact of current tobacco use on the outcome of paracetamol poisoning. Aliment Pharmacol Ther 2003; 18:979.