An injected medicine made of purified salmon DNA fragments, long used to help stubborn wounds heal, is now injected into the scalp for thinning hair. Evidence for regrowth is thin: one small study in women, without a placebo group, not repeated since. Safety looks favorable, with mostly short-lived pain, redness and bruising. For adults already using established hair treatments, it remains an unproven add-on with low apparent risk. (Full Review)
| Marker | Target | Why |
|---|---|---|
| Hair density (trichoscopy) | No established target; track change from own baseline | Primary efficacy measure |
| Hair shaft diameter (trichoscopy) | No established target; track change from own baseline | Thickening often precedes density gain |
| Ferritin | 70–150 ng/mL | Iron stores support hair growth |
| CRP (C-reactive protein) | Paired with ferritin | Ferritin rises with inflammation |
| TSH (thyroid-stimulating hormone) | 1.0–2.5 mIU/L | Thyroid dysfunction causes shedding |
| 25-hydroxyvitamin D | 40–60 ng/mL | Low levels are linked to hair loss |
| Platelet count (complete blood count) | 150–400 × 10⁹/L | Bleeding risk from scalp injections |
| INR, clotting time (warfarin users) | Within the individual's target range | Bruising and hematoma after injections |
| Androgens (women with irregular periods or acne) | Optional baseline test | Documents the hair-loss type |
Cadence: Baseline before starting; photographs and trichoscopy at the same sites at 12 weeks, 24 weeks, then every 6 months while treatment continues; blood tests every 6–12 months only if a baseline value was abnormal. Success: stable or increased density and diameter versus own baseline at 24 weeks, with no new patchy loss or scarring.