Enhanced biotransformation of theophylline in marihuana and tobacco smokers

Clin Pharmacol Ther. 1978 Oct;24(4):405-10.


Single oral doses of theophylline were administered to 7 chronic marihuana smokers, to 7 chronic users of both marihuana and tobacco, and to 43 appropriate control subjects. Theophylline was cleared from the blood more rapidly in both marihuana and tobacco smokers with a mean increase in total clearance from 52 ml/kg/hr in nonsmokers to 74 ml/kg/hr in subjects who smoked either material alone. There was an additive increase in clearance to 93 ml/kg/hr in those who smoked both substances. Concern over enhanced metabolism of other drugs is probably warranted in tobacco and cannabis smokers.

MeSH terms

  • Adult
  • Aminophylline / metabolism
  • Biotransformation
  • Cannabis*
  • Female
  • Humans
  • Kinetics
  • Male
  • Middle Aged
  • Saliva / analysis
  • Smoking / metabolism*
  • Theophylline / blood
  • Theophylline / metabolism*
  • Thiocyanates / blood


  • Thiocyanates
  • Aminophylline
  • Theophylline