RELATIVE BIOAVAILABILITY OF NICOTINE FROM A NASAL SPRAY IN INFECTIOUSRHINITIS AND AFTER USE OF A TOPICAL DECONGESTANT

The relative bioavailability of nicotine from a nasal spray was assess ed in 15 smokers suffering a common cold and rhinitis according to gen erally accepted criteria. The patients were given a single dose of 2 m g nicotine from the nasal spray with and without concurrent administra tion of a nasal vasoconstrictor decongestant, xylometazoline, in rando mised order. Control session measurements were made in the disease-fre e state. Applying strict bioequivalence criteria, we found that common cold/rhinitis slightly reduced the bioavailability of nicotine, both in its rate and extent; the geometric mean of the ratio of C-max, AUC and t(max) were 0.81, 0.93 and 1.36, respectively. The nasal vasoconst rictor, xylometazoline, normalised the extent of the bioavailability o f nicotine, but further prolonged the time for absorption to almost tw ice that measured in the disease-free state, increasing the t(max) rat io to 1.72. The results suggest that a minor proportion of people stop ping smoking with the help of a nicotine nasal spray may experience a minor reduction in the effect of the spray during common cold/rhinitis . However, the nicotine self-titration behaviour found with most smoki ng cessation products (except the nicotine patch) will automatically l ead to an adjustment of the dosage to achieve the desired effect.