Possible effects of increases in amount of free-base nicotine delivered
| Increased oral absorption | → | Increased activation of oral sensory receptors | → | Heightened sensory “cue” for nicotine delivery |
| Increased efficiency of respiratory deposition | → | Greater retention of total smoke nicotine | → | Greater availability of nicotine for deposition/absorption |
| Increased volatility from inhaled particles | → | More rapid absorption of nicotine in lung tissue | → | Reduced time course of delivery to brain |