Sh-Polypeptide-7 is a lab-made copy of the natural growth factor IGF-1, sold in scalp serums. The biology is reasonable, but no human trials of the topical product exist, it penetrates the scalp poorly, too much may worsen hair loss, and safety is unsettled — placing it firmly in the experimental category. (Full Review)

Protocol

Delivery

Microneedling or liposomal/exosome carrier

Intact protein penetrates poorly; delivery is the single most important practical variable.

Application

Twice-daily split dosing

Applied to a clean, dry scalp; rapid local degradation favors split over single daily dosing.

Positioning

Add-on, not a replacement

Practitioners treat it as an adjunct to first-line therapy (minoxidil, finasteride/dutasteride), given weak standalone evidence.

Time to effect

Visible density change

3–6 months

Reflects the hair cycle; no validated timeline exists for topical Sh-Polypeptide-7 specifically.

Benefits

Low: Promotion and prolongation of the hair growth phase (conflicted); adjunctive density gains within growth-factor / regenerative protocols

Speculative: Replacement of follicular IGF-1 deficiency in pattern hair loss; synergy with co-applied growth factors and microneedling

Contraindications

Current or recent malignancy (esp. skin or hormone-sensitive cancers), or active precancerous scalp lesions

Pregnancy or breastfeeding

Acromegaly or other pathologically elevated IGF-1

Active scalp infection, open wounds, or uncontrolled inflammatory scalp disease

Key Interactions

Topical minoxidil

5-alpha-reductase inhibitors (finasteride, dutasteride)

Other topical growth factors and peptides (VEGF, KGF/FGF-7, PDGF, copper peptides)

Microneedling and other barrier-disrupting procedures

Retinoids and exfoliating acids on the scalp

Risk & Side Effects

Medium: Theoretical proliferative and oncological concern from a growth factor

Low: Local scalp irritation, redness, and folliculitis; paradoxical follicle aging from IGF-1 excess

Speculative: Endocrine effects from systemic absorption; unknown effects of contaminants or mislabeled potency

Monitoring

Marker	Target	Why
Hair density (phototrichogram, hairs/cm²)	Stable or increasing vs. baseline	Objective measure of response
Fasting serum IGF-1 (ng/mL)	Age- and sex-adjusted mid-normal range	Screens for systemic elevation if absorption is a concern
Fasting glucose / HbA1c	Glucose <90 mg/dL; HbA1c <5.4%	IGF-1 signaling overlaps insulin signaling; screens metabolic context
Ferritin	40–70 ng/mL (functional target for hair)	Low iron stores independently impair hair growth and confound results
TSH (thyroid-stimulating hormone)	0.5–2.5 mIU/L (functional)	Thyroid dysfunction is a common, treatable cause of hair shedding that confounds results

Cadence: Baseline before starting, then reassess at ~3 months, 6 months, then every 6–12 months

Qualitative Assessment

Reduced daily shedding (hairs on pillow, in shower, on brush)
Subjective scalp coverage and styling ease
Visible regrowth of short, fine "vellus-to-terminal" hairs at the hairline or part
Absence of scalp irritation, redness, or new/changing lesions

Sh-Polypeptide-7 for Hair Regrowth

Protocol

Benefits

Risk & Side Effects

Monitoring

Qualitative Assessment