Comparative effects of tobacco smoking and nasal nicotine.

Objective: Compare the electroencephalographic (EEG) and cardiovascular effects of tobacco smoking and nasal nicotine in the same subjects.

Methods: Eleven volunteer smokers were studied after >10 h of overnight tobacco deprivation. Quantitative EEG was used to measure brain electrical changes produced by four different treatments. Each subject smoked a low (0.08 mg) and average nicotine (1 mg) yield cigarette on one test day and received placebo and nicotine nasal spray (0.5 mg/spray) on a second day in a counterbalanced design. EEG activity was measured from 16 scalp electrodes and analyzed as delta, theta, alpha (1), alpha (2), beta (1), and beta (2) frequency bands. Heart rate (HR), blood pressure (BP), and plasma venous nicotine concentrations (VNC) were monitored during both sessions. EEG data from all 16 channels at each of six frequencies were compared over 10 min using repeated measures ANOVA analysis. Changes in HR, BP, and VNC from baseline were compared using ANOVA followed by post hoc Scheffe's test.

Results: Smoking an average nicotine delivery cigarette resulted in highly significant decreases in alpha (1) activity, significant increases in alpha (2) activity, and significant increases in both HR and VNC compared to all other conditions.

Conclusion: When smokers are allowed to pace themselves, cigarette smoking is far more effective than nasal nicotine in activating the EEG and increasing HR and VNC. This lack of equivalent physiological effects may explain the low success rate when nicotine nasal spray is used by those trying to quit smoking.