[https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8988043/](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8988043/)
 
Conclusion

The rigid biological barrier of the brain (BBB and blood–cerebrospinal barrier) restricts xenobiotics, including therapeutic agents, to enter the brain. Thus, exploring novel strategies of formulation aspects with an alternate route of administration has shown to have a potential impact on brain targeting. Intranasal delivery of therapeutics is proposed to utilize the olfactory and trigeminal pathways to overcome the obstacles imposed by the BBB. Furthermore, this noninvasive route also attracts researchers’ attention, where advanced drug deliveries have shown attractive results in preclinical research. The potential of using novel delivery devices with the polymeric matrix has indicated overcoming the nasomucociliary clearance, thereby allowing prolonged retention of the formulation for constant delivery of therapeutics to the brain. These outcomes are waiting for sufficient safety and efficacy data from the preclinical studies to plan for clinical advancement. The pathways of delivering therapeutics using this intranasal route are yet to be confirmed for reproducible results; thus, this route of drug administration for targeting antipsychotic agents directly to the brain requires future preclinical and clinical investigations.