Quality control and drug-drug interactions between commercially available Metoprolol and Glimepiride tablets

Abstract Quality is paramount and needs to be maintained throughout the shelf life of pharmaceuticals. The current study aimed to evaluate the quality, potency, and drug-drug interaction in an in vivo animal model by using two drugs, namely, metoprolol and glimepiride. Tablets were selected for their physical characteristics, such as shape, size, and color. Quality control tests, such as weight variation, hardness, friability, and disintegration tests, and invitro drug release studies were performed as per USP. Drug-drug interaction and in vivo studies were carried out according to the standard protocol of the animal ethics committee. Quality control tests of both the tablets were within the specified range. The cumulative release percentages of the drugs were 81.12% and 85.36% for Metoprolol Tartrate and Glimepiride, respectively, in a physiological buffer solution within 1 h. The combination of metoprolol and Glimepiride also significantly decreased the blood glucose level in diabetic animals. However, the blood glucose level increased in the group receiving metoprolol only, but the difference was not significant. The result suggested that the formulations are safe. However, the chronic use of this combination requires frequent monitoring of blood glucose level to improve its efficacy and for the patient's safety.

Preparation, characterization and stability study of dutasteride loaded nanoemulsion for treatment of benign prostatic hypertrophy.

Benign prostatic hyperplasia (BPH)is the most common condition in aging men, associated with lower urinary tract symptoms. It is caused due to the augmented levels of the androgen dihydrotestosterone. Dutasteride, a 5α-Reductase inhibitor has been recommended for the treatment of BPH upon oral administration. However, long term oral administration of dutasteride may cause sexual problem in man. Therefore the main objective of this study was to develop transdermal patch having nanoemulsion gel of dutasteride in order to enhance physical and chemical stability and eliminate adverse effect of dutasteride. Optimized nanoemulsion was prepared by aqueous phase-titration method and characterized by droplet size, viscosity and refractive index. In-vitro skin permeation of dutasteride through rat abdominal skin was determined by the Franz diffusion cell.Significant increase in the steady state flux (J ss), permeability coefficient (K p) and enhancement ratio (E r) was observed in optimized nanoemulsion formulation A1 (p < 0.05). The Er of optimized nanoemulsion A1 was found to be 1.52 times with respect to control which indicates transdermal delivery may be better approach for BPH. Stability studies were performed for the period of 3 months. It was found that droplet size, viscosity and refractive index were slightly increased at refrigerator and room temperature in 3 months period. However, the changes in these parameters were not statistically significant (p ≥ 0.05). The shelf-life of optimized nanoemulsion A1 was found to be 2.18 years at room temperature. These results indicated that both physical as well as chemical stability of dutasteride in nanoemulsion formulation.

Rhus coriaria ameliorates insulin resistance in non-insulin-dependent diabetes mellitus (NIDDM) rats.

We have investigated the effect of methanolic extract of Rhus coriaria (RC) on hyperinsulinemia, glucose intolerance and insulin sensitivity in non-insulin-dependent diabetes mellitus (NIDDM) rats. NIDDM was induced by single intraperitoneal injection of streptozotocin (STZ, 100 mg/kg) to 2 days old rat pups. RC (200 mg/kg and 400 mg/kg) was administered orally once a day for 5 weeks after the animals were confirmed diabetic (i.e, 90 days after STZ injection). A group of citrate control rats were also maintained which has received citrate buffer on the 2nd day of their birth. There was a significant increase in blood glucose, glycosylated hemoglobin (HbA1c) and serum insulin levels were observed in NIDDM control rats. Treatment with RC reduced the elevated levels of blood glucose, HbA1c and insulin in the NIDDM rats. An oral glucose tolerance test (OGTT) was also performed in the same groups, in which we found a significant improvement in glucose tolerance in the rats treated with RC. The insulin sensitivity was assessed for both peripheral insulin resistance and hepatic insulin resistance. RC treatment significantly improved insulin sensitivity index (K(ITT)) which was significantly decreased in NIDDM control rats. There was significant rise in homeostasis model assessment of insulin resistance (HOMA-R) in NIDDM control rats whereas RC treatment significantly prevented the rise in HOMA-R in NIDDM treated rats. Our data suggest that methanolic extract of RC significantly delayed the onset of hyperinsulinemia and glucose intolerance and improved insulin sensitivity in NIDDM rats.

Accelerated Stability Testing of a Clobetasol Propionate-Loaded Nanoemulsion as per ICH Guidelines.

The physical and chemical degradation of drugs may result in altered therapeutic efficacy and even toxic effects. Therefore, the objective of this work was to study the stability of clobetasol propionate (CP) in a nanoemulsion. The nanoemulsion formulation containing CP was prepared by the spontaneous emulsification method. For the formulation of the nanoemulsion, Safsol, Tween 20, ethanol, and distilled water were used. The drug was incorporated into an oil phase in 0.05% w/v. The lipophilic nature of the drug led to the O/W nanoemulsion formulation. This was characterized by droplet size, pH, viscosity, conductivity, and refractive index. Stability studies were performed as per ICH guidelines for a period of three months. The shelf life of the nanoemulsion formulation was also determined after performing accelerated stability testing (40°C ± 2°C and 75% ± 5% RH). We also performed an intermediate stability study (30°C ± 2°C/65% RH ± 5% RH). It was found that the droplet size, conductivity, and refractive index were slightly increased, while the viscosity and pH slightly decreased at all storage conditions during the 3-month period. However, the changes in these parameters were not statistically significant (p≥0.05). The degradation (%) of the optimized nanoemulsion of CP was determined and the shelf life was found to be 2.18 years at room temperature. These studies confirmed that the physical and chemical stability of CP were enhanced in the nanoemulsion formulation.