Parenteral formulation of zopiclone

The present study was undertaken with an intention to develop a stable and effective parenteral formulation, containing the drug zopiclone. Since zopiclone is a water insoluble drug, various methods such as co-solvency, pH control and hydrotrophy have been tried in order to enhance its solubility. When all these methods could not give adequate solubility enhancement of the drug, a hydrochloride salt was prepared, and it was found to be thermostable. Various batches of zopiclone hydrochloride injection formulation were prepared in order to assess the influence of light, atmospheric oxygen and antioxidant on the stability of the drug and the formulations were also subjected to accelerated stability testing in order to predict approximate shelf-life of the product.