Intranasal Spray Calculator

How intranasal peptide delivery works

The nasal mucosa provides a large surface area with a dense submucosal capillary network, allowing certain peptides to cross into systemic circulation without passing through the gastrointestinal tract. Standard nasal spray pumps deliver a fixed volume per actuation, typically 100 µL. The mass delivered per spray is therefore simply concentration multiplied by volume: a 1 mg/mL solution at 100 µL per actuation delivers 100 mcg per spray. This is volumetric arithmetic, not a pharmacokinetic model.

Intranasal bioavailability varies widely by compound. Small, lipophilic molecules tend to absorb more efficiently than larger, hydrophilic peptides. For context, human studies with intranasal oxytocin typically dose at 24 IU per administration (approximately 72 mcg), while nootropic peptides such as Semax and Selank have been studied at 300–600 mcg per day in their Russian clinical literature. None of this constitutes a dosing recommendation; it is background context for calibrating the inputs you enter. Djupesland et al. (2014) provides a useful overview of nasal drug delivery device design and its influence on deposition.

Dead volume in the pump mechanism (the dip tube and actuator channel) means the first 2–3 actuations from a new bottle may prime the pump rather than deliver full spray volume. For dose-tracking purposes, this calculator assumes a primed pump. In practice, prime the device before counting doses. FDA guidance on nasal spray drug products (2002) defines how spray content uniformity and delivered volume are validated for commercial products.