Computer-based formulation design and optimization using Hansen solubility parameters to enhance the delivery of ibuprofen through the skin.

Trial-and-error approach to formulation development is long and costly. With growing time and cost pressures in the pharmaceutical industry, the need for computer-based formulation design is greater than ever. In this project, emulgels were designed and optimized using Formulating for Efficacy™ (FFE) for the topical delivery of ibuprofen. FFE helped select penetration enhancers, design and optimize emulgels and simulate skin penetration studies. pH, viscosity, spreadability, droplet size and stability of emulgels were evaluated. Franz cell studies were performed to test in vitro drug release on regenerated cellulose membrane, drug permeation in vitro on Strat-M® membrane and ex vivo on porcine ear skin, a marketed ibuprofen gel served as control. Emulgels had skin compatible pH, viscosity and spreadability comparable to a marketed emulgel, were opaque and stable at 25 °C for 6 months. Oleyl alcohol (OA), combined with either dimethyl isosorbide (DMI) or diethylene glycol monoethyl ether (DGME) provided the highest permeation in 24 h in vitro, which was significantly higher than the marketed product (p < 0.01). OA + DGME significantly outperformed OA ex vivo (p < 0.05). The computer predictions, in vitro and ex vivo penetration results correlated well. FFE was a fast, valuable and reliable tool for aiding in topical product design for ibuprofen.

Erythema nodosum leprosum and HIV infection: A therapeutic experience.

The relationship between leprosy and HIV infection is not yet fully understood, as not much is known about the natural history of the co-infected patients. The matter has become more confusing because of conflicting reports. Type-1 lepra reactions and neuritis appear to be severe and more frequent among them. But erythema nodosum leprosum too is not as uncommon among these patients as it was once thought. Management of these co-infected patients is often difficult for want of clear-cut guidelines on clinical care. We report here our experience of treating recurrent, severe erythema nodosum leprosum in a patient concurrently having leprosy and HIV infection. Early institution of antiretroviral therapy appears to provide an edge in improving the therapeutic outcome for him. It also suggests a direct and more complex interplay of HIV and Mycobacterium leprae infection.