Neuropeptide Y (NPY)
Also known as: NPY
A stress-response neuropeptide that modulates anxiety, appetite, and circadian rhythm. Researched for anxiety reduction and stress resilience.
Research Status
Clinical trials
For research purposes only. Not approved for human use. Not medical advice.
Research Areas
Side Effects
Typically resolve within 1-2 hours. Minimize by allowing solution to reach room temperature, using proper injection technique, and rotating sites. Apply ice if swelling persists.
May occur within hours of injection. Usually self-resolving. Ensure adequate hydration and consider timing of injection relative to meals.
More common with higher doses or rapid dosing escalation. Sit or lie down if experienced. Typically resolves within 30 minutes.
May occur shortly after injection. Take with food or ginger if bothersome. Usually transient and dose-dependent.
NPY naturally stimulates feeding behavior. This is an expected pharmacological effect. Monitor food intake if weight management is a concern.
Timing of injection may influence circadian effects. Evening dosing may promote sleep; morning dosing may cause alertness. Adjust timing based on individual response.
Develops with repeated injections at the same site. Prevent by strict site rotation. Rotate systematically and maintain a log. Effects may be reversible if rotation is implemented early.
Seek immediate medical attention if rash, swelling of face/throat, or difficulty breathing occurs. Discontinue use and do not re-administer.
NPY modulates emotional regulation. Some users report improved mood; others may experience emotional shifts. Monitor mental state and discontinue if significant mood disturbance occurs.
NPY has cardiovascular effects. Monitor blood pressure, especially in users with hypertension history. Discontinue if sustained elevation occurs.
Dosing Reference
| Parameter | Value |
|---|---|
| Dose range | 0.5-2 mcg |
| Frequency | 1-2x daily |
| Timing | Morning and/or evening, or as directed by research protocol |
| Route | Subcutaneous |
Research dosing varies widely depending on study design and route of administration. Intranasal and subcutaneous routes are most common in human research. Start conservatively and titrate based on response. For research purposes only.
Research disclaimer
Figures drawn from published research literature and community logs. Not clinical recommendations. Consult a qualified professional. Research use only.
Reconstitution Guide
Do not use saline or bacteriostatic saline — use only bacteriostatic water for reconstitution
Do not shake the vial vigorously; gentle swirling prevents peptide degradation
Discard immediately if the solution appears cloudy, discolored, or contains visible particles
Use within 30 days of reconstitution when stored at 2–8°C
Do not freeze the reconstituted solution; freezing may denature the peptide
Use the PeptideVolt reconstitution calculator for your exact concentration
Molecular and Pharmacological Data
| Molecular weight | 4382 |
| Half-life | 1-2 minutes (in circulation); longer in CNS due to receptor binding and local effects |
| Sequence | YPSKPDNPGEDAPAEDLARYYSALRHYDVWNVQRSVQ |
Neuropeptide Y (NPY) is an endogenous 36-amino acid neuropeptide that acts primarily through Y1 and Y2 receptors in the central and peripheral nervous systems. It modulates stress responses, anxiety, appetite regulation, and circadian rhythms by influencing hypothalamic-pituitary-adrenal (HPA) axis activity and neurotransmitter systems. NPY is particularly abundant in the amygdala, hippocampus, and hypothalamus, where it exerts anxiolytic and stress-buffering effects.
HPA Axis Modulation
NPY inhibits corticotropin-releasing hormone (CRH) and reduces hypothalamic-pituitary-adrenal axis activation, thereby lowering cortisol and ACTH levels during stress. This mechanism underlies its anxiolytic and stress-resilience effects.
Amygdala GABAergic Signaling
NPY enhances GABAergic inhibitory neurotransmission in the amygdala through Y1 receptor activation, reducing anxiety-related neural activity and promoting emotional regulation.
Appetite and Energy Homeostasis
NPY acts on Y1 and Y5 receptors in the hypothalamus to stimulate feeding behavior and regulate energy expenditure, particularly during periods of stress or caloric restriction.
Circadian Rhythm Regulation
NPY neurons in the suprachiasmatic nucleus (SCN) receive light input and regulate circadian-dependent hormone secretion, including melatonin and cortisol patterns.
Neuroprotection and Neuroplasticity
NPY promotes neuronal survival, reduces excitotoxicity, and supports synaptic plasticity through Y1 and Y2 receptor signaling in the hippocampus and cortex.
- NPY is one of the most abundant neuropeptides in the mammalian brain and is highly conserved across species
- Y1 receptors mediate anxiolytic and stress-buffering effects; Y2 receptors modulate appetite and energy balance
- NPY levels are naturally elevated during chronic stress and may represent an endogenous stress-resilience mechanism
- Intranasal and subcutaneous administration can cross the blood-brain barrier or directly access CNS tissue
- NPY deficiency is associated with increased anxiety, depression, and impaired stress coping in animal models
- The peptide has been investigated in clinical trials for anxiety disorders, PTSD, and stress-related conditions
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View all peptidesResearch Use Only. All content on this page is provided for informational and educational purposes related to scientific research. Neuropeptide Y (NPY) is not approved for human use by the FDA or any equivalent regulatory body. This is not medical advice. Do not use any substance discussed here for therapeutic, diagnostic, or preventative purposes. Consult a qualified healthcare professional before making any health-related decisions. The Peptide Volt does not endorse the use of any research chemicals. 18+ only.