Medication effectiveness relies on patient adherence to a given treatment regimen. Often, patients do not adhere to the temporal guidelines set by their physicians and treatments therefore remain less effective. In situ forming implants (ISFIs) eliminate the need for patient adherence and release an effective dose of drug overtime. However, no methods exist to noninvasively and temporally validate drug release in vivo. We conducted in vivo experiments that validated the use of DWI to monitor ISFI diffusivity overtime. This has enormous implications in pharmaceutical research as this method can robustly quantify diffusivity in ISFIs post-implantation to ensure effective drug release.