Correlation of Phenylpropanolamine Bioavailability with Gastrointestinal Transit by Scintigraphic Monitoring of 111In-Labeled Hydroxypropylmethylcellulose Matrices

Two controlled-release hydroxypropylmethylcellulose (HPMC) matrix formulations, a single-unit and a multiple-unit system, have been evaluated in human volunteers. Both formulations contained the sympathomimetic drug phenylpropanolamine hydrochloride and each was radiolabeled with ¹¹¹Inbound Amberlite IR 120 ion-exchange resin. The formulations were administered to each of six healthy male volunteers and gastrointestinal (GI) transit was monitored using a gamma camera. Serum samples were taken at set time intervals and assayed for phenylpropanolamine content, thus allowing blood drug levels to be correlated with the position of the dosage form in the GI tract. The multiple-unit system emptied from the stomach gradually over a period of about 180 min, when administered after a light breakfast, whereas the single-unit dosage forms had extremely variable gastric emptying times (range, 60 to >570 min). However, both formulations provided prolonged phenylpropanolamine blood levels. The differences in the blood profiles obtained with the two formulations were attributed to variations in their in vitro release rates and not to any differences in their GI transit times.     

Proximal Hamstring Ruptures: Treatment,Rehabilitation, and Return to Play

Purpose of ReviewTo assess the current literature surrounding the treatment and rehabilitation strategies surrounding proximal hamstring rupture injuries, along with comparative return to sport and patient-reported outcomes.Recent FindingsA high degree of variability exists in protective and rehabilitation strategies after both operative and non-operative proximal hamstring rupture management. Acceptable outcomes after both operative and non-operative management have been observed but may vary greatly with injury chronicity, severity, and surgical technique.SummaryThe high complication rates observed after surgical treatment, along with poor functional outcomes that may occur in the setting of non-operative treatment or delayed surgery, highlight the importance of early injury evaluation and careful patient selection. Further high-quality research elucidating clearer indications for early operative management and an optimized and standardized rehabilitation protocols may improve outcomes and return to sport experience and metrics for individuals sustaining proximal hamstring ruptures.