Abstract
Clarithromycin (CM), a broad spectrum macrolide antibiotic used to eradicate H. pylori
in peptic ulcer. Clarithromycin (CM) is well absorbed from the gastrointestinal tract,
but has a bioavailability of 50% due to rapid biodegradation. The aim of this investigation
was to increase the gastric residence time, and to control the drug release of clarithromycin
by formulating into multiple unit floating mini-tablets. Floating tablets were prepared
by using direct compression method with HPMC K4 M and Polyox WSR 1105 as release retarded polymers and sodium bicarbonate as gas generating
agent. The prepared mini-tablets were evaluated for thickness, weight variation, friability,
hardness, drug content, in vitro buoyancy, swelling studies, in vitro dissolution
studies by using modified Rossett-Rice test and in vivo radiographic studies in healthy
human volunteers in fasting conditions. DSC analysis revealed that no interaction
between drug and excipients. All the physical parameters of the tablets were within
the acceptable limits. The optimized formulation (F6) had showed controlled drug release
of 99.16±3.22% in 12 h, by zero-order release kinetics, along with floating lag time
of 9.5±1.28 s and total floating time of 12±0.14 h. X-ray imaging studies revealed
that in vivo gastric residence time of clarithromycin floating mini-tablet in the
stomach was about 3.5 h. The results demonstrated that the developed floating mini-tablets
of clarithromycin caused significant enhancement in gastric retention time along with
sustained effect and increased oral bioavailability.
Key words H. Pylori - clarithromycin - floating mini tablets - in vitro release - X-ray study
