Aims
To characterize and compare the pharmacokinetic profiles of bromazepam, omeprazole and paracetamol when administered by the oral and nasogastric routes to the same healthy cohort of volunteers.
Methods
In a prospective, monocentric, randomized crossover study, eight healthy volunteers received the three drugs by the oral (OR) and nasogastric routes (NT). Sequential plasma samples were analyzed by high-performance liquid chromatography–UV, pharmacokinetic parameters (Cmax, $${\text{AUC}}_{0 - \infty } $$ , t½, ke, tmax) were compared statistically, and Cmax, $${\text{AUC}}_{0 - \infty } $$ and tmax were analyzed for bioequivalence.
Results
A statistically significant difference was seen in the $${\text{AUC}}_{0 - \infty } $$ of bromazepam, with nasogastric administration decreasing availability by about 25%: AUCOR = 2501 ng mL−1 h; AUCNT = 1855 ng mL−1 h (p < 0.05); ratio (geometric mean) = 0.74 [90% confidence interval (CI) 0.64–0.87]. However, this does not appear to be clinically relevant given the usual dosage range and the drug’s half-life (approx. 30 h). A large interindividual variability in omeprazole parameters prevented any statistical conclusion from being drawn in terms of both modes of administration despite their similar average profile: AUCOR = 579 ng mL−1 h; AUCNT = 587 ng mL−1 h (p > 0.05); ratio (geometric mean) = 1.01 (90% CI 0.64–1.61). An extended study with a larger number of subjects may possibly provide clearer answers. The narrow 90% confidence limits of paracetamol indicate bioequivalence: AUCOR = 37 μg mL−1 h; AUCNT = 41 μg mL−1 h(p > 0.05); ratio (geometric mean) = 1.12 (90% CI 0.98–1.28).
Conclusion
The results of this study show that the nasogastric route of administration does not appear to cause marked, clinically unsuitable alterations in the bioavailability of the tested drugs.