SUMMARY
Pathological conditions of the digestive system are quite common nowadays and rank first among other human diseases. Increasingly, both newly-diagnosed and recurrent cases of stomach ulcers, as well as duodenal ulcers are recorded. Among solid drug dosage forms capsules are considered to be the most rational since the drug substance exhibits a low degree of dispersion, which leads to better absorption, resists additional negative impact in the production process, as well as possesses a lower damaging action on the mucous membranes of the digestive tract, etc. Thereby capsules are more and more often recommended for use by preference. Therefore, developing a feasible method of quantitative determination of metronidazole in capsules – the method of spectrophotometry in the ultraviolet region of the spectrum has become particularly urgent since high performance liquid chromatography recommended by the BP and USP is not used widely in Ukraine. The object of research was metronidazole capsules. The research has found that the excipients have little effect on the absorption spectrum of metronidazole obtained by extraction with 0.1 M hydrochloric acid solution from the content of capsules. The test solution has been proven to be complied with the Beer-Lambert-Bouguer law within the concentration range of 0.5·10-3% – 3.0·10-3%. The certification of the method developed on the model mixtures and a production sample has confirmed its correctness. The average results uncertainty e in the former case was 0.11%, whereas in the latter it constituted 0.70%.