Drug Quality Characteristics

Regarding drug quality characteristics, researchers evaluated different features: the packaging of the drugs purchased, the instructions included, and the chemical composition.

As to packaging characteristics, packaging showed problems in more than half of the drug samples in the GAO [73] study. Memmel et al [83] found that all packaging appeared legitimate and products were within the expiration date, but patient education material (instructions) did not always match the product. GAO [73] researchers found better quality instructions in samples from US and Canadian Internet pharmacies, which in all 47 samples included dispensing pharmacy labels that generally provided patient instruction for use and in 87% of cases included warning information, compared with other foreign pharmacies, whose labeling and facility of manufacture were not FDA approved in the majority (19/21) of cases. Westenberger et al [104] found that only 1 of 20 samples had final packaging, including package insert, similar to that of the US products. The final packaging of the remainder consisted of bubble wrap inside a paper envelope, a Styrofoam sheet inside a paper envelope, loose blister packs, capsules or tablets in clear plastic bags without labels, and capsules or tablets in opaque plastic containers or boxes with labels. Bate and Hess [59] reported that many drugs, including some that did not fail in spectrometry testing, had an unclear or problematic origin or problematic packaging. In the European Alliance for Access to Safe Medicines study [65], 47% of the drugs purchased had no packaging, and in 6% the packaging had been tampered with; half of the sample supplied a patient leaflet, which was in English in 80% of cases. Mainous and colleagues’ [82] purchase arrived with no instructions.

The GAO [73] found that the chemical composition of 4 samples out of 68 was not comparable with the product ordered: in 2 cases a counterfeit version contained less active ingredients, and in 2, a significantly different chemical composition from the product ordered. An analysis of counterfeit dapoxetine (a short-acting selective serotonin-reuptake inhibitor), used against premature ejaculation, found that the tablets contained undisclosed sildenafil [102]. Bate and Hess’s [59] analysis showed that 2.5% (3/121) of the tablet sample failed Raman spectrometry. Westenberger et al [104] found that 2 out of 20 samples failed in terms of dissolution and chromatographic purity; Veronin and Youan in 2004 [103] found differences in simvastatin tablet formulation, obtained from 5 countries via the Internet, using near-infrared spectroscopy chemical imaging methods to assess blend uniformity. In contrast, Veronin et al in 2007 [94] found a quality standard comparable with that of the American manufacturer and the Canadian generic drug product tested. The European Alliance for Access to Safe Medicines study [65] study found that 62% of the products received were counterfeit, substandard, or unapproved medications (68% of these were generic and 32% were branded).

Date: 2016-03-03; view: 946