Clinical Comparison · Hair Restoration
PRP vs i-PRF: What's the difference, and which is better for hair?
A clear, clinically-grounded comparison of Platelet-Rich Plasma (PRP) and injectable Platelet-Rich Fibrin (i-PRF) — the second-generation form of PRF used for hair restoration.
PRP vs i-PRF at a glance
The clinical comparison, side by side. (i-PRF is the injectable form of PRF used for hair restoration.)
| PRP | i-PRF | |
|---|---|---|
| Full name | Platelet-Rich Plasma | Injectable Platelet-Rich Fibrin |
| Generation | First generation (1990s–) | Second generation (2014–) |
| Centrifugation | High-speed (~3,000+ rpm, 10–15 min) | Low-speed (~700 rpm, 3–5 min) |
| Anticoagulant | Required (citrate / EDTA) | None — fully autologous |
| Form on injection | Liquid plasma only | Liquid that forms a fibrin gel |
| Growth factor release | Rapid: hours | Sustained: 7–10 days |
| Leukocyte content | Variable, often lower | Higher (preserved by low spin) |
| Stem cell content | Lower | Higher |
| Typical course | 3–6 monthly sessions | 3–6 sessions |
| Typical cost (UK) | Lower per session | Higher per session |
| Best suited to | Early-stage thinning, budget-led plans | Advanced thinning, post-PRP plateau, fewer-sessions protocols |
What is PRP?
Platelet-Rich Plasma (PRP) is a concentrated preparation of platelets isolated from a patient's own blood. A small blood draw is processed in a centrifuge at high speed, separating red blood cells from a plasma fraction enriched with platelets. PRP has been used in regenerative medicine since the 1990s and entered hair restoration in the 2000s.1
Platelets carry growth factors — including platelet-derived growth factor (PDGF), vascular endothelial growth factor (VEGF), and transforming growth factor beta (TGF-β) — which signal nearby cells to proliferate, recruit blood supply, and rebuild tissue. When injected into the scalp, PRP releases these factors quickly, stimulating dormant follicles and supporting the hair growth cycle.
A 2017 systematic review of nine PRP studies for androgenetic alopecia reported significant increases in hair density of 12.3 to 45.9 hairs/cm² (a 19–31% improvement) in seven of those studies.2 A 2025 phase I trial showed PRP injections increased hair count by approximately 62% and hair thickness by 58.6% after two sessions.3
PRP requires the addition of an anticoagulant (typically sodium citrate or EDTA) to prevent clotting during processing. The result is a liquid that releases its growth factors rapidly, usually within hours of injection.
What is i-PRF?
i-PRF (injectable Platelet-Rich Fibrin) is the second-generation evolution of PRP, developed by Choukroun and colleagues. It is the liquid, injectable form of PRF — the broader fibrin-based platelet concentrate family. It is prepared from the same starting material as PRP (the patient's own blood) but processed differently in two important ways.
First, i-PRF uses no anticoagulants. The blood is drawn directly into a sterile tube and spun immediately, before clotting can occur. Second, the centrifugation is slower (around 700 rpm for 3–5 minutes) compared to the high-speed spin used for PRP. This is known as the Low-Speed Centrifugation Concept (LSCC).4
The result is a preparation that naturally polymerises into a soft fibrin matrix — a three-dimensional scaffold that traps platelets, leukocytes, stem cells, and growth factors. This matrix is the central difference. Growth factors are released gradually over 7–10 days rather than hours, providing prolonged biological signalling at the injection site. Studies using ELISA quantification have shown i-PRF preparations contain higher concentrations of platelets, leukocytes, and growth factors (particularly VEGF and TGF-β1) compared to traditional PRP.45
A Note on Terminology
What's the difference between PRF and i-PRF?
PRF (Platelet-Rich Fibrin) refers to the broader family of fibrin-based platelet concentrates. Standard PRF forms a solid clot used in dental and oral surgery. i-PRF is the injectable, liquid form developed using the Low-Speed Centrifugation Concept — kept fluid long enough to inject before it polymerises at the treatment site.
For hair restoration, i-PRF is the form used. When clinics or articles say "PRF for hair," they almost always mean i-PRF. Read about i-PRF Hair Restoration at GlowMedix Clinic →
Clinical evidence for i-PRF in hair restoration
A 2025 prospective study published in Archives of Dermatological Research followed 30 patients with androgenetic alopecia who had previously responded inadequately to conventional treatments. Each received six monthly i-PRF injections. The study reported significant improvements in hair density, hair shaft diameter, and reductions in vellus hair percentage and scalp inflammation, with a favourable safety profile.6
A 2024 systematic review encompassing seven studies and 130 patients confirmed that, for androgenetic alopecia specifically, three studies of 22 patients reported noticeable improvements in hair density and growth following i-PRF therapy.7 An earlier 2018 study of injectable PRF for AGA published in Dermatologic Surgery reported similar positive outcomes.8
The Five Key Differences
PRP vs i-PRF: where they actually differ
Boiled down to the five differences that matter clinically.
Centrifugation speed
PRP uses high-speed centrifugation (~3,000 rpm) to separate red blood cells aggressively from plasma. i-PRF uses low-speed centrifugation (~700 rpm) for a shorter time.
The slower spin preserves more leukocytes and stem cells in the final preparation.4
Anticoagulant use
PRP requires anticoagulants (sodium citrate or EDTA) to remain liquid during preparation. i-PRF uses no additives at all.
This makes i-PRF fully autologous — no foreign substances added — and allows the natural formation of a fibrin matrix after injection.
Fibrin matrix
Once injected, i-PRF naturally polymerises into a soft three-dimensional fibrin gel that traps platelets, leukocytes, and growth factors at the injection site. PRP remains liquid plasma — no scaffold forms.
The matrix is the structural reason for i-PRF's prolonged biological effect.
Growth factor release
PRP releases growth factors rapidly — most are exhausted within hours of injection. i-PRF releases them gradually over 7–10 days, providing sustained signalling to follicles and surrounding tissue.
This sustained-release profile is widely considered the most significant clinical advantage of i-PRF.4
Cellular composition
The low-speed centrifugation used for i-PRF preserves a higher proportion of platelets, leukocytes, and stem cells than high-speed PRP protocols. ELISA quantification has confirmed elevated VEGF and TGF-β1 concentrations in i-PRF.5
More cells, more signalling molecules, more biological activity per session.
Same starting material. Different processing. Different result.
Choosing Between Them
Which one is right for you?
A starting framework — final treatment decisions are made in clinical consultation.
Rabia Gilani
Rabia is a registered Pharmacist Prescriber with a clinical interest in dermatology and trichology. She is founder of GlowMedix Clinic and CEO of GLOWMEDIX Hair, with thousands of regenerative hair treatments delivered across the clinic's three London locations.
Medical oversight is provided by Dr Syed Hassan (MBBS, MRCGP), the clinic's Medical Director. Read more about the team.
Frequently Asked Questions
Common questions about PRP and i-PRF
PRP (Platelet-Rich Plasma) is a liquid plasma concentrate prepared with anticoagulants and high-speed centrifugation that releases growth factors rapidly within hours. i-PRF (injectable Platelet-Rich Fibrin) is processed at a lower centrifugation speed without anticoagulants, producing a fibrin matrix that releases growth factors slowly over 7–10 days. i-PRF typically contains higher concentrations of platelets, leukocytes, and growth factors than PRP.
Current clinical evidence suggests i-PRF may produce comparable or superior outcomes to PRP for androgenetic alopecia, due to its higher growth factor concentration and sustained release profile. A 2025 prospective study of 30 patients in Archives of Dermatological Research demonstrated significant improvements in hair density and shaft diameter with i-PRF.6 Both treatments remain effective options, and the best choice depends on individual factors assessed at consultation.
PRP and PRF differ in centrifugation speed, anticoagulant use, and growth factor release. PRP uses high-speed spinning with anticoagulants and releases growth factors rapidly. PRF uses low-speed spinning without anticoagulants and forms a fibrin matrix that releases growth factors over 7–10 days. For hair restoration, the injectable form of PRF — known as i-PRF — is the form used.
i-PRF stands for injectable Platelet-Rich Fibrin. It is the liquid, injectable form of PRF developed by Choukroun and colleagues using the Low-Speed Centrifugation Concept. Standard PRF forms a solid clot used in dental and oral surgery, while i-PRF remains liquid long enough to be injected before polymerising into a fibrin matrix at the injection site. For hair restoration, i-PRF is the form used.
No. i-PRF is prepared without anticoagulants such as sodium citrate or EDTA. This is one of the key differences from PRP, which typically requires an anticoagulant to remain liquid during preparation. The absence of anticoagulants allows i-PRF to form a natural fibrin matrix.
PRP for hair restoration is typically administered as a course of 3–6 monthly sessions, followed by maintenance every 6–12 months. i-PRF protocols may use fewer sessions due to the sustained release of growth factors. A 2025 clinical study used six monthly i-PRF sessions for androgenetic alopecia.6 Final session count depends on the individual patient and severity of hair loss.
i-PRF is typically priced higher per session than PRP because of additional preparation requirements and the more advanced biological profile. However, because fewer sessions may be required, the total course cost can be comparable. At GlowMedix Clinic, i-PRF Hair Restoration starts from £299 per session.
Yes. Patients who have plateaued on PRP often transition to i-PRF for a stronger response. The two treatments use the same biological principle — concentrating components of the patient's own blood — so a switch is straightforward and does not require a washout period.
Both PRP and i-PRF use the patient's own blood, so the risk of allergic reaction is extremely low. Common side effects include mild scalp tenderness, redness, and minor bruising at injection sites, typically resolving within 24–48 hours. Both are generally considered safe when performed by qualified medical practitioners.
Patients with active scalp infections, blood disorders such as thrombocytopenia, those on blood-thinning medications, or those with certain autoimmune conditions may not be suitable. Pregnant or breastfeeding patients are generally advised to defer treatment. Suitability is determined at clinical consultation.
References
Clinical references
- Mishra S, Kumar A, Chatterjee K. Platelet-Rich Plasma in Androgenetic Alopecia. Indian Dermatol Online J. 2021;12(Suppl 1):S43-S52. PMC8664169
- Picard F, Hersant B, Bosc R, Meningaud JP. Injections of platelet-rich plasma for androgenic alopecia: A systematic review. J Stomatol Oral Maxillofac Surg. 2017. PubMed PMID: 28676455
- Nilforoushzadeh MA, Roohaninasab M, Behrangi E, et al. Phase I Clinical Trial: Evaluating the Efficacy, Safety, and Patient Satisfaction of Platelet-Rich Plasma (PRP) Injections and Microneedling for Androgenetic Alopecia Treatment. J Cosmet Dermatol. 2025. PMC12442246
- Choukroun J, Ghanaati S. Reduction of relative centrifugation force within injectable platelet-rich-fibrin (PRF) concentrates advances patients' own inflammatory cells, platelets and growth factors: the first introduction to the low speed centrifugation concept. Eur J Trauma Emerg Surg. 2018;44(1):87-95. PMC5808086
- Fujioka-Kobayashi M, Miron RJ, Hernandez M, Kandalam U, Zhang Y, Choukroun J. Optimized Platelet Rich Fibrin With the Low Speed Concept: Growth Factor Release, Biocompatibility and Cellular Response. J Periodontol. 2017. PubMed PMID: 27786620
- Karagün E, Yıldız P, Bozdoğan Ö. New tool in our arsenal: efficacy of injectable platelet-rich fibrin (i-PRF) in androgenetic alopecia treatment. Arch Dermatol Res. 2025. Springer · PubMed PMID: 40009221
- Cervantes J, Perper M, Wong LL, et al. Effectiveness of Injectable Platelet-Rich Fibrin Therapy in Alopecia and Facial Rejuvenation: A Systematic Review. Cureus. 2024. PMC11247247
- Schiavone G, Paradisi A, Ricci F, Abeni D. Injectable Platelet-, Leukocyte-, and Fibrin-Rich Plasma (iL-PRF) in the management of androgenetic alopecia. Dermatol Surg. 2018;44(9):1183-1190. PubMed PMID: 30134307
- Arora R, Shukla S. Injectable-Platelet-Rich Fibrin-Smart Blood with Stem Cells for the Treatment of Alopecia: A Report of Three Patients. Int J Trichology. 2019;11(3):128-131. PMC6580805