Formulation Strategies and Therapeutic Applications of Shikonin and Related Derivatives

Shikonin and its derivatives are excellent representatives of biologically active naphthoquinones. A wide range of investigations carried out in the last few decades validated their pharmacological efficacy. Besides having magnificent therapeutic potential, shikonin and its derivatives suffer from various pharmacokinetic, toxicity, and stability issues like poor bioavailability, nephrotoxicity, photodegradation, etc. Recently, various research groups have developed an extensive range of formulations to tackle these issues to ease their path to clinical practice. The latest formulation approaches have been focused on exploiting the unique features of novel functional excipients, which in turn escalate the therapeutic effect of shikonin. Moreover, the codelivery approach in various drug delivery systems has been taken into consideration in a recent while to reduce toxicity associated with shikonin and its derivatives. This review sheds light on the essential reports and patents published related to the array of formulations containing shikonin and its derivatives.