Exploring Nose to Brain Nano Delivery for Effective Management of Migraine

Abstract

Migraine is a disabling disease characterized by severe throbbing headaches. Patients demand quick relief from this pain. The presence of the blood-brain barrier does not permit the drug to penetrate the brain effectively. Administration of conventional anti-migraine medications via oral route leads to erratic absorption of drugs. Delayed gastric emptying is also responsible for the ineffective absorption of the drug. Migraine-induced nausea and vomiting further limit patient compliance to oral medication. Other limitations associated with the oral route include extensive first-pass metabolism, slow onset of action, inability to cross the blood-brain barrier, requirement of a large amount of dose/dosage, and frequent administration. The anti-migraine drugs used in migraine, such as triptans, are therapeutically effective but have low bioavailability on oral administration. Also, these drugs are associated with several cardiovascular complications. The oral dose of most antimigraine drugs, oral triptans, Ergotamine, NSAIDs, and CGRP antagonists is quite high because of their poor bioavailability. As a result, these drugs are associated with several side effects. This aspect necessitates the need to develop a dosage form that can deliver drugs directly to the brain, thereby reducing the dose. Invasive techniques to deliver these therapeutics to the brain do exist. However, they are painful, require expert assistance, and are not a cost-effective approach for migraine treatment. These limitations demand the development of a novel non-invasive approach that is safe, efficacious, and has high patient compliance. According to reports, it is possible to target the brain tissue by administering the drug intranasally using the olfactory and the trigeminal pathway. This route is non-invasive, avoids first-pass metabolism, eliminates nausea and vomiting, helps reduce dose, and thus helps achieve increased patient compliance. Some factors like solubility, the lipophilicity of the drug, mucociliary clearance, and enzymatic degradation hinder the bioavailability of the drug by nasal route. Therefore, there is a grave need to develop novel nasal formulations with prolonged nasal residence time, which can modulate pharmacokinetics for adequate therapeutic response and render efficient yet robust brain targeting. Considering these challenges, developing an efficient intranasal dosage form is necessary. This review gives a brief overview of all the novel carriers reported for improving the treatment of migraine. Nanocarrier-based delivery systems like in situ gels, microemulsion, nanoemulsion, nanoparticles, vesicular systems, micelles, and microspheres used in nose to brain delivery of migraine therapeutics are also discussed in the article.

Keywords: Migraine; brain targeting; intranasal; nanocarriers; nose-to-brain drug delivery; olfactory pathway; trigeminal pathway.