Postmarketing pharmacokinetic and pharmacodynamic equivalence of generic and brand atenolol in Egypt

Concerns have raised regarding the postmarketing quality of generic drugs. This study assessed the pharmacokinetic and pharmacodynamic equivalence of generic and brand atenolol tablets in 24 healthy male volunteers in a single-dose, open, randomized, two-period crossover study under fasting conditions. Blood samples were collected for 24 h post dosing and assayed for atenolol using HPLC. Blood pressure and heart rate were measured at baseline and throughout blood sampling. The mean plasma concentration-time curves for both products were similar. Pharmacokinetic and statistical analysis indicated bioequivalence based on the mean ratios of log-transformed Cmax and AUC values. Both products had similar time courses of pharmacodynamic activity with a significant fall in blood pressure and heart rate [maximum after 5 h] followed by a gradual increase towards baseline. Both products were well tolerated. Both atenolol products were bioequivalent in the postmarketing setting and can be used interchangeably in clinical practice

Assessment of the pharmaceutical quality of omeprazole capsule brands marketed in Egypt

The pharmaceutical quality of 7 local omeprazole capsule brands in Egypt was assessed relative to the proprietary product [Losec[R]]. Drug content, content uniformity, drug release [using USP test for enteric coated articles and a modified release test] were determined. Products were subjected to a 3-month stability study. Of the 7 brands, 6 had satisfactory drug content and content uniformity. All brands passed the USP drug release test. The modified release test proved to be more discriminative. After 3 months storage, drug content of 3 brands remained > 90% and 2 of these brands maintained drug release above 75%. Changes in pellet appearance during storage were indicative of omeprazole chemical degradation

Dissolution of cholesterol in bile salt solutions: effect of a nonionic surfactant [triton X-114]

A nonionic surfactant, Triton X-114, was shown to increase the dissolution rate of cholesterol in bile salt solutions, the effect being concentration dependent. The dissolution data obtained with Triton X-114 using a series of dihydroxy and trihydroxy bile salts and those obtained with cetrimIde indicate that the accelerating effect of the nonionic surfactant may involve the formation of bile salt-nonionic surfactant systems of higher solubilizing capacity for cholesterol which enhances the dissolution process. The results obtained provide information on this class of compOunds as potential cholesterol dissolution enhancers