Quality of amoxicillin formulations in some Arab countries

BACKGROUND AND OBJECTIVE

The problem of counterfeit and substandard drugs is recurrent in developing countries where antibiotics account for the majority of such products. The aim of this study was to investigate the quality of locally produced and imported amoxicillin products on the Lebanese, Jordanian, Egyptian and Saudi markets.

METHODS

One hundred and eleven samples of amoxicillin capsules and suspensions purchased from retail pharmacies were analysed for their drug content by a validated chromatographic method in order to verify if they complied with pharmacopeial requirements. Suspensions were analysed for their drug content immediately after reconstitution as well as 7 or 14 days later according to the expiry date.

RESULTS AND DISCUSSIONS

Fifty-six per cent of amoxicillin capsules did not meet the United State Pharmacopeia (USP) requirements and most had amounts bordering the lower limit. Individual average values as low as 59% of the label claim were detected. Eight per cent of the samples of suspensions gave measurements outside pharmacopeial limits. Furthermore, after 7 or 14 days, 38% of the samples were outside the pharmacopeial limits. All the European brands met the pharmacopeial limits except for one.

CONCLUSION

Our results reveal the high incidence of substandard drugs on some Arab market where several factors might jeopardize the quality status of medicines: lack of effective quality assurance system during manufacture in both Arab and export countries, and uncontrolled storage conditions, especially unsuitable pharmacy premises. Use of substandard antibiotic preparations increases the risk of therapeutic failure and the emergence of drug-resistant microorganisms.

High-amylose carboxymethyl starch matrices for oral sustained drug-release: In vitro and in vivo evaluation

High-amylose corn starch, that contains 70% of amylose chains and 30% of amylopectin, has been used to obtain substituted amylose (SA) polymers. Tablets have been prepared by direct compression, i.e. dry mixing of drug and SA, followed by compression, which is the easiest way to manufacture an oral dosage form. Until now, their controlled-release properties have been assessed only by an in vitro dissolution test. Amylose-based polymers are normally subject to biodegradation by alpha-amylase enzymes present in the gastrointestinal tract, but matrix systems show no significant degradation of tablets by alpha-amylase in vitro. High-amylose sodium carboxymethyl starch (HASCA) is an interesting excipient for sustained drug-release in solid oral dosage forms. In addition to the easy manufacture of tablets by direct compression, the results show that in vitro drug-release from an optimized HASCA formulation is not affected by either acidic pH value or acidic medium residence time. In addition, a compressed blend of HASCA with an optimized quantity of sodium chloride provides a pharmaceutical sustained-release tablet with improved integrity for oral administration. In vivo studies demonstrate extended drug absorption, showing that the matrix tablets do not disintegrate immediately. Nevertheless, acetaminophen does not seem to be the most appropriate drug for this type of formulation.

Scholastic impairments among traumatized adolescents

This investigation sought to determine if exposure to exceptional stress is associated with academic deficits or whether academic deficits are specifically associated with post-traumatic stress disorder (PTSD). In order to address these questions, the Metropolitan Achievement Test (MAT) as well as a measure of intelligence were administered to three groups of Lebanese adolescents. The first group met diagnostic criteria for PTSD. The second group had been exposed to qualitatively and quantitatively similar stressors but did not meet diagnostic criteria for PTSD. The third group consisted of nontraumatized controls. Data analysis using IQ as a covariate determined that the MAT scores of the PTSD subjects were significantly lower than the scores of the stress exposed PTSD negatives and controls. No significant differences were observed when the MAT scores of the stress exposed PTSD negatives and controls were compared.

Self-efficacy expectations among traumatized adolescents

Bandura's Multidimensional Scales of Perceived Self-Efficacy (MSPSE) were administered to three matched groups of adolescents. The first group met diagnostic criteria for PTSD. The second had been exposed to qualitatively and quantitatively similar stressors and did not meet criteria for PTSD (traumatized PTSD negatives). The third group consisted of non-traumatized controls. Data analysis revealed that the adolescents with PTSD had appreciably lower self-efficacy ratings on eight of the nine subtests that comprise the MSPSE. Non-significant differences were observed when the MSPSE subtest scores of the traumatized PTSD negatives and controls were compared.