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Peptide profile

Skin & hair Animal data

Tetrapeptide-21 (Ganirelix analog)

Tetrapeptide for hair follicle activation

Compare Tetrapeptide-21 (Ganirelix analog) with other peptides →

Summary

Hair growth peptide for follicle stimulation.

A hair peptide that wakes up your hair roots.

Typical dose
2.5-5% concentration 1x daily
Route
Topical
Cycle length
3-6 months
Evidence
Animal data

Mechanism

How it works

This hair peptide acts like a growing season extender for hair follicles — it keeps them in the active growth phase longer before shedding.

Tetrapeptide-21 stimulates dermal papilla cells, prolongs anagen phase, and reduces dihydrotestosterone (DHT) binding to follicles.

Tetrapeptide-21 stimulates dermal papilla cells, prolongs anagen phase, and reduces dihydrotestosterone (DHT) binding to follicles.

Reported in research

Benefits

  • Stimulates hair follicle proliferation
  • Increases anagen (growth) phase duration
  • Reduces follicular inflammation
  • Potential for androgenetic alopecia
  • Helps your hair roots make more hair
  • Keeps hair growing for a longer time
  • Calms down swelling around hair roots
  • May help with a common type of hair loss

Context, not a prescription

Dosing

Typical range
2.5-5% concentration 1x daily (Topical)
Cycle length
3-6 months

Safety

Side effects & contraindications

Possible side effects

  • Minimal topical irritation
  • Mild redness
  • Contact dermatitis

Contraindications

  • Pregnancy or breastfeeding
  • Known peptide sensitivity

Research information, not medical advice. Always consult a licensed clinician before considering any peptide.

In depth

Full profile

What it does

Thicker, fuller hair and less hair falling out.

How it works

Think of it like making summer last longer for your hair. It keeps your hair growing for more time before it falls out.

It connects to special cells at your hair roots. This turns on a growth signal and turns down the hormone that hurts hair.

What to expect

You can see results in about 3 to 4 months.

  • Weeks 4-8: You lose less hair than before.
  • Months 2-3: Tiny new baby hairs start to show up.
  • Months 4-6: Hair gets fuller and thicker.

Good to know

  • Test it on a small skin spot first
  • Put it on a clean, dry scalp

Staying safe

  • A little skin irritation
  • Slight redness

Avoid if you have:

  • Pregnant or breastfeeding moms
  • People who react badly to peptides

Overview

Increased hair density, reduced shedding, thicker hair shafts.

How it works

This hair peptide acts like a growing season extender for hair follicles — it keeps them in the active growth phase longer before shedding.

Binds to receptors on dermal papilla cells, activating Wnt/β-catenin and reducing androgen receptor activity.

Onset & timeline

Visible results at 3-4 months.

  • Weeks 4-8: Reduced shedding.
  • Months 2-3: New vellus hairs appear.
  • Months 4-6: Increased density and thickness.

Getting the most from it

  • Patch test before use
  • Apply to clean, dry scalp

Common side effects

  • Minimal topical irritation
  • Mild redness

Mechanism of action

Tetrapeptide-21 stimulates dermal papilla cells, prolongs anagen phase, and reduces dihydrotestosterone (DHT) binding to follicles.

Binds to receptors on dermal papilla cells, activating Wnt/β-catenin and reducing androgen receptor activity.

Pharmacodynamics

Visible results at 3-4 months.

Increased hair density, reduced shedding, thicker hair shafts.

Timeline

  • Weeks 4-8: Reduced shedding.
  • Months 2-3: New vellus hairs appear.
  • Months 4-6: Increased density and thickness.

Comparisons

  • Tetrapeptide-21 — effectiveness Emerging, safety Good, cost $$, Easy to use
  • Minoxidil — effectiveness Moderate, safety Good, cost $, Easy to use

Adverse effects

Common:

  • Minimal topical irritation
  • Mild redness

Rare:

  • Contact dermatitis

Contraindications & risk mitigation

Contraindicated in:

  • Pregnancy or breastfeeding
  • Known peptide sensitivity
  • Patch test before use
  • Apply to clean, dry scalp

Qué hace

Cabello más grueso y abundante, con menos caída.

Cómo funciona

Piensa en ello como hacer que el verano dure más para tu cabello. Mantiene tu cabello creciendo por más tiempo antes de que se caiga.

Se conecta con células especiales en tus raíces del cabello. Esto activa una señal de crecimiento y reduce la hormona que daña el cabello.

Qué esperar

Puedes ver resultados en aproximadamente 3 a 4 meses.

  • Semanas 4-8: Notarás menos caída de cabello que antes.
  • Meses 2-3: Empiezan a aparecer pequeños vellos nuevos.
  • Meses 4-6: El cabello se vuelve más abundante y grueso.

Bueno saber

  • Haz una prueba en una pequeña zona de la piel primero
  • Aplica en un cuero cabelludo limpio y seco

Manteniéndose seguro

  • Un poco de irritación en la piel
  • Enrojecimiento leve

Evitar si tienes:

  • Mujeres embarazadas o en lactancia
  • Personas con reacción adversa a péptidos

Descripción general

Mayor densidad capilar, reducción de la caída, tallos capilares más gruesos.

Cómo funciona

Este péptido capilar actúa como un extensor de la temporada de crecimiento para los folículos: los mantiene en la fase activa por más tiempo antes de la caída.

Se une a receptores en las células de la papila dérmica, activando Wnt/β-catenina y reduciendo la actividad de los receptores androgénicos.

Inicio y cronología

Resultados visibles a los 3-4 meses.

  • Semanas 4-8: Reducción de la caída.
  • Meses 2-3: Aparecen nuevos vellos.
  • Meses 4-6: Aumento de la densidad y el grosor.

Cómo aprovecharlo al máximo

  • Prueba de parche antes de usar
  • Aplicar en el cuero cabelludo limpio y seco

Efectos secundarios comunes

  • Irritación tópica mínima
  • Enrojecimiento leve

Mecanismo de acción

El Tetrapéptido-21 estimula las células de la papila dérmica, prolonga la fase anágena y reduce la unión de la dihidrotestosterona (DHT) a los folículos.

Se une a receptores en las células de la papila dérmica, activando Wnt/β-catenina y reduciendo la actividad de los receptores androgénicos.

Farmacodinamia

Resultados visibles a los 3-4 meses.

Mayor densidad capilar, reducción de la caída, tallos capilares más gruesos.

Cronología

  • Semanas 4-8: Reducción de la caída.
  • Meses 2-3: Aparecen nuevos vellos.
  • Meses 4-6: Aumento de la densidad y el grosor.

Comparaciones

  • Tetrapéptido-21 — efectividad Emergente, seguridad Buena, costo $$, Fácil de usar
  • Minoxidil — efectividad Moderada, seguridad Buena, costo $, Fácil de usar

Efectos adversos

Comunes:

  • Irritación tópica mínima
  • Enrojecimiento leve

Raros:

  • Dermatitis de contacto

Contraindicaciones y mitigación de riesgos

Contraindicado en:

  • Embarazo o lactancia
  • Sensibilidad conocida a péptidos
  • Prueba de parche antes de usar
  • Aplicar en el cuero cabelludo limpio y seco

Reference data

Specifications

Route
Topical
Cycle length
3-6 months

FAQ

Common questions

Is it effective for male pattern baldness?

Emerging research suggests benefit by reducing DHT effects, but weaker than finasteride.

Can it regrow hair?

Moderate regrowth in early studies; best for maintenance of existing hair.

What is the evidence level?

This compound is classified as Animal data. Most data comes from preclinical animal studies. Human clinical trial evidence is limited or absent.

Research

Research & sources

Animal data

Current evidence for Tetrapeptide-21 (Ganirelix analog) is rated as Animal data. Research is based primarily on animal models.

  1. 1. Tetrapeptide hair growth (2018) — DOI:10.1111/jocd.12457
  2. 2. Peptides in alopecia (2020) — DOI:10.1111/ics.12614
  3. 3. Tetrapeptide hair growth (2018)
  4. 4. Peptides in alopecia (2020)