RESUMEN
Objective:To analyze the causes of microbial contamination in methadone hydrochloride oral solution used for the ma-intenance treatment of heroin addict in Guangxi and propose the relative countermeasures. Methods:The samples of methadone hydro-chloride oral solution were obtained from 10 maintenance treatment clinics, and then the microbial limit test and identification were per-formed,the content of preservative was detected and the relationship between the preservative content and microbial contamination was studied. Results:The total number of aerobe in the samples of methadone hydrochloride oral solution from the 10 clinics was all over the standard limit value of 100 cfu·ml-1 ,and the main contaminating germ was Burkholderia cepacia. The contents of sorbic acid were 78. 2％-98. 3％,the four batches with the lowest concentration of preservative were detected with higher total number of aerobe. Con-clusion:The microbial contamination in methadone hydrochloride oral solution from the 10 maintenance treatment clinics is severe,and the environment of medicine packaging, content of preservatives, packaging machine and storage conditions are the primary causes for the microbial contamination. To ensure drug quality safety, it is suggested that the environment cleanliness of medicine packaging be improved, suitable content of preservatives be added, packaging machine be clean, the products be stored in shade and the quality be tested regularly.