Intranasalis

Intranasalis, from the Latin roots for “through the nose,” is commonly used in English as an adjective describing delivery or administration via the nasal cavity. In medical and pharmaceutical contexts, intranasal delivery refers to formulations designed to release a drug or diagnostic agent across the nasal mucosa for local or systemic effects. Preparations include sprays, drops, gels, and powders intended for nasal application.

Mechanistically, intranasal administration takes advantage of the highly vascularized nasal mucosa and the large surface area of the nasal cavity. Absorption can provide relatively rapid onset of action, with some portion of the drug reaching systemic circulation while bypassing part of the gastrointestinal first-pass metabolism. The route is also used to target local nasal conditions, such as congestion or allergic rhinitis, where a local effect is desired.

Applications and examples vary widely. Intranasal delivery is common for acute treatment of migraines (for example, certain triptans), for emergency reversal of opioid overdose with intranasal naloxone, and for some vaccines and vaccines-adjuvant formulations intended to induce mucosal and systemic immunity. Other agents include hormonal therapies, antibiotics, and decongestants, all formulated for nasal administration to maximize ease of use and rapidity of effect. Some molecules, particularly larger proteins or peptides, may require specialized formulations or devices to enhance absorption and stability.

Limitations include variability in absorption due to nasal mucosal condition, potential irritation or congestion, risk of epistaxis, and manufacturing constraints to ensure stability and precise dosing. Safety and efficacy depend on proper indications, device use, and patient characteristics, such as nasal pathology and age.