What Peptides Can Be Taken Nasally? A Complete Intranasal Guide
By Spirare Research | Last Updated: May 2026
Peptides that are commonly used intranasally in research contexts include Semax, Selank, NA Semax Amidate, Oxytocin, PT-141, DSIP, Dihexa, VIP, KPV, Epithalon, and GHK-Cu. These peptides are small enough to cross the nasal mucosa and, in some cases, reach the central nervous system via the olfactory pathway.
This guide covers what the research community currently knows about intranasal peptide delivery, which compounds are most commonly prepared as nasal sprays, and what protocols are generally referenced in research contexts.
Disclaimer: This content is for informational and educational purposes only. All peptides discussed here are for research use only. This is not medical advice. Always consult a qualified healthcare provider before beginning any peptide protocol.
Why the Intranasal Route Matters
Not all delivery routes are equal for every compound. The nasal mucosa offers a large surface area, a rich blood supply, and - critically - a direct connection to the brain via the olfactory and trigeminal nerve pathways.
For certain peptides, intranasal delivery may allow compounds to bypass the blood-brain barrier entirely, delivering them directly to central nervous system tissue. This is the core reason neurological peptides like Semax and Selank were specifically engineered for intranasal use.
Peptide size and structure are the primary gating factors for nasal suitability. Diluent choice and preparation technique also matter in research contexts, which is why having the right equipment makes a meaningful difference.
For a full breakdown of how to calculate your concentration and dose, use the free Intranasal Peptide Preparation Calculator.
Peptides Most Commonly Used Intranasally
1. Semax
Research Dose: 200–1,000 mcg per day, 1–3 intranasal administrations
Cycle: 2–4 weeks on / 1–2 weeks off
Storage: 36–46°F (2–8°C)
Semax is a synthetic heptapeptide derived from the ACTH(4-10) fragment, developed in Russia and specifically approved there for intranasal clinical use. Anecdotal reports and preclinical data describe potential nootropic, neuroprotective, and mood-related properties. Its structural stability makes it one of the most reliable peptides for intranasal research use.
2. Selank
Research Dose: 600–900 mcg per day, 1–3 sprays
Cycle: 2–8 weeks
Storage: 36–46°F (2–8°C)
Selank is a heptapeptide based on the immunomodulatory peptide tuftsin, with a Pro-Gly-Pro extension added for enzymatic stability. Like Semax, it was designed specifically for intranasal administration in Russian research settings. Anecdotal reports describe potential anxiolytic and cognitive properties, with detectable effects reported within minutes of administration in research contexts.
3. NA Semax Amidate (N-Acetyl Semax Amidate)
Research Dose: 600–1,200 mcg per day, 1–2 administrations
Cycle: 10–30 days
Storage: 36–46°F (2–8°C)
NA Semax Amidate is a modified version of Semax featuring both N-terminal acetylation and C-terminal amidation. These modifications are reported in research contexts to increase potency and extend duration of action relative to standard Semax. It is increasingly used by researchers seeking longer-acting nootropic effects from intranasal delivery.
4. Oxytocin
Research Dose: 24–40 IU (2–4 sprays of a 10 IU/spray solution)
Storage: 36–46°F (2–8°C)
Oxytocin is arguably the most clinically studied intranasal peptide in existence. Syntocinon, a pharmaceutical oxytocin nasal spray, was previously FDA-approved before being discontinued. Numerous peer-reviewed human trials have examined intranasal oxytocin's potential effects on social cognition, bonding, and behavior, with well-documented nasal absorption and demonstrated central nervous system effects.
5. PT-141 (Bremelanotide)
Research Dose: 1–2 mg per dose
Storage: 36–46°F (2–8°C)
PT-141 was originally developed and clinically trialed specifically as a nasal spray, targeting melanocortin receptors in the central nervous system. Anecdotal reports from the research community describe potential effects on libido and sexual function. While a subcutaneous injectable form later received FDA approval for a specific indication, intranasal research use of PT-141 remains common due to the convenience of the delivery method.
6. DSIP (Delta Sleep-Inducing Peptide)
Research Dose: 100–150 mcg intranasally, typically administered in the evening
Storage: 36–46°F (2–8°C)
DSIP is a small nonapeptide with reported sleep-modulating properties in preclinical research. Its compact structure makes it a strong candidate for intranasal delivery. Anecdotal reports describe use before sleep as part of broader recovery or sleep optimization protocols in research contexts. Vial sizes are typically 5mg.
7. Dihexa
Research Dose: 50 mcg intranasally, up to 4x daily
Storage: 36–46°F (2–8°C)
Dihexa is a small, lipophilic peptide with cognitive enhancement properties reported in preclinical research. Its compact size and lipophilic character make it well-suited for intranasal delivery. Anecdotal reports suggest it is increasingly prepared as a nasal spray by researchers interested in nootropic protocols.
8. VIP (Vasoactive Intestinal Peptide)
Research Dose: 50 mcg per nostril, typically 2x daily
Storage: 36–46°F (2–8°C)
VIP is a larger peptide than most others on this list but has legitimate clinical research behind intranasal delivery. It has been studied for potential anti-inflammatory and immune-modulating properties. Intranasal use is documented in research literature, though absorption can be less predictable than smaller compounds.
9. KPV
Research Dose: 100–300 mcg per day, 1–2 administrations
Storage: 36–46°F (2–8°C)
KPV is a tripeptide fragment of alpha-MSH with potential anti-inflammatory properties reported in preclinical data. Its extremely compact structure makes it one of the most favorable candidates for nasal absorption. Research interest has grown among those exploring intranasal delivery for systemic and CNS anti-inflammatory effects.
10. GHK-Cu (Copper Peptide)
Research Dose: 100–200 mcg per nostril
Storage: 36–46°F (2–8°C)
GHK-Cu is best known as a topical compound, but some researchers have begun exploring intranasal delivery for potential cognitive and anti-inflammatory effects. Its compact tripeptide structure is favorable for nasal absorption. Intranasal protocols are less standardized than topical use, but anecdotal reports of nasal administration exist in the research community.
11. Epithalon (Epitalon)
Research Dose: 1–3 mg per administration (protocols vary)
Storage: 36–46°F (2–8°C)
Epithalon is a synthetic tetrapeptide studied primarily for its potential effects on telomerase activity and longevity markers. Its small size makes it theoretically well-suited for nasal delivery. Preclinical research has noted potential neurological effects via intranasal administration, though most published research uses injectable routes and intranasal protocols are less standardized.
Peptides That Are Generally Not Suitable for Intranasal Use
Some commonly researched peptides are not well-suited for nasal delivery:
- TB-500 - Too large for reliable nasal absorption.
- Cerebrolysin - Injectable only; not a candidate for intranasal preparation.
- IGF-1, HGH, Semaglutide, Tirzepatide - Size and structural characteristics make intranasal delivery unreliable.
How to Prepare a Peptide Nasal Spray
Preparing a peptide nasal spray for research use requires the right equipment. The Spirare Supply Intranasal Peptide Preparation Kit includes everything needed to reconstitute and load a nasal spray correctly - calibrated 100µL atomizers, sterile saline, appropriately sized syringes, alcohol prep pads, and printed preparation instructions.
The standard reconstitution protocol using the kit:
- Dump the full 5mL saline ampoule into the nasal spray bottle.
- Draw 1mL of saline back out using a syringe.
- Inject that 1mL slowly into the peptide vial to reconstitute. Aim along the side of the glass - do not inject directly onto the powder.
- Gently roll to dissolve. Do not shake.
- Draw the full reconstituted solution back and inject it into the spray bottle with the remaining 4mL saline.
- Prime 3–4 pumps before first use.
This yields approximately 200 mcg per spray for a standard 10mg peptide vial. For different vial sizes or target concentrations, use the Intranasal Peptide Preparation Calculator to adjust.
For a full walkthrough of the math, see the complete intranasal preparation guide.
A Note on Diluent Choice for Nasal Use
For intranasal research, sterile 0.9% saline is generally preferred over bacteriostatic water. The preservative agent (benzyl alcohol) in bacteriostatic water can be irritating to nasal mucosa with repeated use. Saline is gentler and better tolerated for nasal delivery.
Frequently Asked Questions
What is the most commonly used intranasal peptide?
Semax and Selank are the most established intranasal peptides in the research community. Both were specifically designed for nasal delivery in Russia and have the most documented use via this route.
How many sprays do you get from a 10mg peptide vial?
Using 5mL of saline with a 100µL pump, a 10mg vial yields approximately 50 sprays at 200 mcg per spray. Changing the diluent volume changes the concentration per spray - use the peptide calculator to run your specific numbers.
Why not just use an insulin syringe instead of a nasal spray bottle?
Insulin syringes are designed for subcutaneous injection - short fixed needles, very fine gauge, and significant dead space make them unsuitable for peptide vial reconstitution and nasal delivery. A nasal atomizer with a calibrated pump is the correct tool for intranasal research use.
What determines if a peptide can be taken nasally?
Peptide size and structure are the most important factors, but not the only ones. Lipophilicity, solution pH, osmolality, and nasal mucosa health all influence absorption. Smaller, more compact peptides generally absorb most predictably via the nasal route.