intranasales

Intranasal administration, or intranasales, delivers substances through the nasal cavity to achieve systemic or local effects. The nasal mucosa is highly vascularized, allowing rapid absorption into the bloodstream, and for some agents there is potential direct access to the central nervous system via olfactory and trigeminal pathways.

Delivery methods include sprays, drops, gels, and dry powders designed for intranasal use. Formulations may target rapid onset or sustained delivery and are delivered with metered-dose sprays, droppers, or specialized devices.

Uses include systemic medications such as analgesics and anti-migraine drugs, nasal decongestants, and emergency therapies like naloxone nasal spray. Intranasal vaccines and vaccine candidates aim to induce mucosal and systemic immunity; examples include intranasal influenza vaccines. Research also explores intranasal delivery of peptides and hormones, and ongoing work seeks nasal insulin formulations.

Advantages include needle-free administration, rapid onset, and avoidance of first-pass metabolism. Limitations include absorption variability due to nasal conditions, mucosal irritation, and limited suitability for large or unstable molecules. Efficacy can be affected by nasal congestion and mucociliary clearance, which can shorten residence time in the nasal cavity.

Safety considerations focus on local adverse effects such as irritation and epistaxis, risk of infection, and potential systemic effects if potent compounds are absorbed. Nasal anatomy and pathology can influence absorption, and product-specific recommendations guide use.