3 ghk cu serum Best Copper Peptide 1 to relieve the appearance of redness and work to restore and strengthen your skin barrier Copper Peptide GHK-CU Face Serum,

But if it expires after 28 days, you only get 4 doses from that vial (10mg used) before discarding the remaining 20mg

[Corrected]

doi:10.1039/C5CS00889A

These two delaying factors are why patients with low B12 levels are often prescribed B12 shots instead of oral supplements

For a smaller dose: 10,000mcg vial + 2mL = 5,000mcg/mL

Phase 2 Side-Effect Frequencies at 4.5 mg/week (Lancet 2021) Side Effect Nausea Incidence at 4.5 mg/week 47% Side Effect Injection-site reactions Incidence at 4.5 mg/week 43% Side Effect Constipation Incidence at 4.5 mg/week 21% Side Effect Fatigue Incidence at 4.5 mg/week 20% Side Effect Allergic reactions (any) Incidence at 4.5 mg/week 10% Side Effect Vomiting Incidence at 4.5 mg/week 8% Side Effect Loose stools Incidence at 4.5 mg/week 7% Side Effect Headache Incidence at 4.5 mg/week 7% Side Effect Indigestion Incidence at 4.5 mg/week 4% Incidence was lower at lower doses