Intranasal Drug Delivery for CNS - PMC
/PMC/2026
Why It Matters
This caught my attention because it's a practical delivery route that's already being used clinically. If you're interested in nootropics or neuroprotective compounds, understanding that intranasal administration can deliver drastically higher brain concentrations than oral routes matters for both efficacy and safety. The challenge is that most compounds aren't formulated for this—just because something works orally doesn't mean snorting it will work better.
Key Findings
- Direct nose-to-brain transport via olfactory (bypassing blood-brain barrier) and trigeminal nerve pathways can achieve brain drug levels 100-fold higher than intravenous administration for some compounds
- Intranasal insulin has shown cognitive benefits in Alzheimer's patients in clinical trials, with minimal impact on blood glucose—demonstrating CNS selectivity of this route
- Delivery efficiency depends heavily on formulation factors: particle size (10-50 microns optimal), mucoadhesive properties, and pH matching nasal mucosa (5.5-6.5)
- Rapid nasal mucociliary clearance (15-20 minutes) limits absorption window, requiring specialized formulations with penetration enhancers or mucoadhesive agents
- Already FDA-approved intranasal CNS drugs include sumatriptan (migraine), esketamine (depression), and naloxone (overdose reversal)—this isn't theoretical, it's clinically validated
Read the Paper↗PMC12197310