Hair Growth Cycle and How PRP Therapy Enhances Natural Hair Regrowth

By Dr. Debra Durst, MD – Founder, RevitalyzeMD

Healthy hair growth depends on a natural, continuous cycle consisting of three primary phases—Anagen (growth), Catagen (transition), and Telogen (resting/shedding)—plus a shedding phase called Exogen. Understanding these phases helps you see how treatments like PRP therapy interact with your scalp to stimulate thicker, healthier hair.

• Active growth phase where hair follicles produce new hair.
• Lasts 2–7 years, influenced by genetics, hormones, and overall health.
• Approximately 85–90% of scalp hair is in this phase at any time.
• Hair grows about ½ inch per month during anagen.

PRP Effect: Platelet-rich plasma prolongs the anagen phase by stimulating dermal papilla cells, resulting in thicker and healthier hair growth.

• Short phase lasting 2–3 weeks where hair growth stops.
• Hair follicles shrink and detach from their blood supply.
• Only 1–2% of hair is in catagen at any given time.

PRP Effect: PRP can delay catagen onset, keeping hair follicles in the growing phase longer and maximizing hair density.

• Lasts about 3–4 months, where follicles are dormant before shedding.
• Roughly 10–15% of scalp hairs are in this phase at any time.
• New hairs grow underneath old hairs, eventually pushing them out.

PRP Effect: PRP reduces premature shedding by improving follicle health and activating dormant follicles to re-enter the anagen phase.

• Recognized as the active shedding phase where old hairs fall out to make way for new growth.
• Normal hair loss ranges from 50–100 hairs per day.

PRP Effect: PRP accelerates follicle turnover, ensuring timely replacement of shed hair with new growth.

• Platelet-Rich Plasma (PRP) therapy leverages your own growth factors to regenerate and revitalize hair follicles.
  • Increases blood supply to follicles, delivering essential nutrients and oxygen.
  • Releases key growth factors:
  • VEGF (Vascular Endothelial Growth Factor) – promotes blood vessel formation
  • EGF (Epidermal Growth Factor) – stimulates cell growth and healing
  • PDGF (Platelet-Derived Growth Factor) – encourages follicle regeneration
  • Strengthens hair shafts, enhancing thickness and quality.
  • Reduces inflammation around follicles, a common contributor to hair loss.

  PRP is especially effective for androgenetic alopecia (pattern hair loss) and telogen effluvium, helping reverse follicle miniaturization and restore healthier hair cycles.

• Maintain a balanced diet rich in protein, vitamins, and minerals.
• Manage stress to prevent premature hair shedding.
• Avoid excessive heat styling and harsh chemical treatments.

Consider scalp massages or professional hair growth treatments to improve circulation.

Stress, hormonal changes, aging, and nutrition impact the duration and health of each hair growth phase. Treatments like PRP can enhance natural cycles but are most effective when combined with healthy lifestyle habits. By understanding how your hair grows, you can optimize your results and choose the most suitable Hair Restoration solutions.