Therefore, the rationale for attaching caffeine to DHA (caffeine-DHA) is primarily to target the delivery of caffeine to over-expressed striatal A2ARs. In addition to carrying caffeine to A2AR-containing membranes, DHA may also promote its retention in the target tissue, increasing the interaction time between caffeine and A2AR. Furthermore, DHA has been considered a neuroprotective or even a disease-modifying agent in the treatment of PD [21]. Here, ADORA2A is linked to Parkinson disease.