Quality of omeprazole purchased via the Internet and personally imported into Japan: comparison with products sampled in other Asian countries

Abstract

Abstractobjective To evaluate the quality of omeprazole personally imported into Japan via the Internet and to compare the quality of these samples with previously collected samples from two other Asian countries.methods The samples were evaluated by observation, authenticity investigation and pharmacopoeial quality analysis. Quality comparison of some selected samples was carried out by dissolution profiling, Raman spectroscopy and principle component analysis (PCA).results Observation of the Internet sites and samples revealed some discrepancies including the delivery of a wrong sample and the selling of omeprazole without a prescription, although it is a prescription medicine. Among the 28 samples analysed, all passed the identification test, 26 (93%) passed the quantity and content uniformity tests and all passed the dissolution test. Dissolution profiling confirmed that all the personally imported omeprazole samples remained intact in the acid medium. On the other hand, six samples from two of the same manufacturers, previously collected during surveys in Cambodia and Myanmar, frequently showed premature omeprazole release in acid. Raman spectroscopy and PCA showed significant variation between omeprazole formulations in personally imported samples and the samples from Cambodia and Myanmar.conclusions Our results indicate that the pharmaceutical quality of omeprazole purchased through the Internet was sufficient, as determined by pharmacopeial tests. However, omeprazole formulations distributed in different market segments by the same manufacturers were of diverse quality. Measures are needed to ensure consistent quality of products and to prevent entry of substandard products into the legitimate supply chain.

A Comprehensive Analysis of Select Medicines Collected from Private Drug Outlets of Dhaka City, Bangladesh in a Simple Random Survey

“…The poor dissolution rates of the samples were a persistent problem, an observation which had previously been reported in our studies [56,57,60,61]. As an essential indicator of bioavailability and drug quality, the dissolution test has not been given as much attention as it deserves [58,62,63]. Despite the fact that all of the ESM samples contained the stated amount of API, a poor dissolution rate was observed in the buffer stage of the dissolution test in 10.9% of the ESM samples (Table 3; Figs.…”

“…The drug dissolution test is a good predicator for the sample performance test, while allowing observation of physicochemical changes in tablets/granules in capsules [57][58][59]. The results presented in this study demonstrate that 5.3% samples (95% CI, 0.021-0.086) were non-compliant (including all tested samples but excluding the falsi ed samples).…”

A comprehensive analysis of selected medicines collected from private drug outlets of Dhaka city, Bangladesh in a simple random survey

“…The poor dissolution rates of the samples were a persistent problem, an observation which had previously been reported in our studies 60 , 61 , 64 , 65 . As an essential indicator of bioavailability and drug quality, the dissolution test has not been given as much attention as it deserves 62 , 66 , 67 . Despite the fact that all of the ESM samples contained the stated amount of API, a poor dissolution rate was observed in the buffer stage of the dissolution test in 10.9% of the ESM samples (Table 3 ; Figs.…”

Quality and Authenticity of Metformin Tablets Circulating on Japanese Websites

“…In previous studies, we found that falsified weight-loss and erectile dysfunction drugs containing no active pharmaceutical ingredient [ 18 – 20 ]. Even when drugs are not falsified, the quality of a drug produced by the same manufacturer can differ according to the place of origin and market [ 21 ] In Southeast Asia, the circulation of low-quality metformin has been confirmed [ 12 ]. However, the quality and authenticity of metformin circulating on the Internet remain unclear.…”