Donnelly Ronald F
Hosp Pharm. 2016 Dec;51(11):915-921. doi: 10.1310/hpj5111-915.
The combination of levodopa and carbidopa (L/C) is used as an effective therapy for treating Parkinson's disease; however when oropharyngeal dysphagia develops or when insertion of an nasogastric tube is not possible, then rectal administration could be used. To reduce compounding workload and establish a beyond use date, this study was conducted to determine the stability of 2 L/C rectal suspension formulations when stored at either 22°C or 5°C. Two formulations of L/C rectal suspension were compounded and then packaged in amber polypropylene bottles. Three bottles of each formulation were stored at either 22°C or 5°C and analyzed at 11 time periods. Physical parameters such as caking, ease of resuspending, and pH were also determined at each time period. A validated stability-indicating high-performance liquid chromatography (HPLC) method was used to analyze both active ingredients. All solutions were easy to resuspend, there were no signs of caking, and there was no significant change in pH over the 35 days of storage at either temperature. The glycerin-based formulation (formulation 1) was less stable at 22°C (10 days) than formulation 2 (24 days). Both rectal suspensions were stable for 35 days when stored at 5°C. The physical compatibility and chemical stability of 2 formulations of L/C rectal suspension packaged in amber polypropylene bottles was determined to be either 10 or 24 days when stored at 22°C or 35 days at 5°C.
左旋多巴和卡比多巴的组合制剂（L/C）被用作治疗帕金森病的有效疗法；然而，当出现口咽吞咽困难或无法插入鼻胃管时，则可采用直肠给药。为了减少配制工作量并确定有效期，本研究旨在测定两种L/C直肠混悬液制剂在22°C或5°C储存时的稳定性。配制了两种L/C直肠混悬液制剂，然后包装在琥珀色聚丙烯瓶中。每种制剂的三瓶分别储存在22°C或5°C下，并在11个时间点进行分析。在每个时间点还测定了诸如结块、再悬浮难易程度和pH值等物理参数。采用经过验证的稳定性指示高效液相色谱（HPLC）法分析两种活性成分。所有溶液都易于再悬浮，没有结块迹象，并且在两种温度下储存35天期间pH值均无显著变化。甘油基制剂（制剂1）在22°C下（10天）比制剂2（24天）稳定性差。两种直肠混悬液在5°C储存时35天内均稳定。包装在琥珀色聚丙烯瓶中的两种L/C直肠混悬液制剂的物理相容性和化学稳定性在22°C储存时为10天或24天，在5°C储存时为35天。
