ABSTRACT
It had been done a study on the assay and potency of three samples of Tetracycline Hydrochloride visually having different colours. The study on the assay of the three samples of Tetracycline Hydrocloride was done by using pectrophotometric method in alkaline media, while the study on their potency was done by using turbidimetric method with latin square pattern. The result obtained are as follows: - The change in colour that is significant in samples of Tetra cycline Hydrochloride examined, does not affect their contents or potency. - The spectrophotometric method has precision difference in-. significantly compared with turbidimetric one. With respect to the above results it is still necessary to look for the correlation between the amount of the content of anhydrotetracycline and its effect on spectrophotometric and turbidimetric method.