What did @itsjessandreasen actually say?
She described consistent local reactions after injecting GHK-Cu subcutaneously, including redness, swelling, itching, and burning that she compared to "a bad bug bite." She said she has rotated through her belly, thighs, hips, and glutes trying to find a tolerable site, and was experimenting with her lats on the day of filming. She also mentioned trying NAD (presumably NAD+ infusion or injection) and experiencing flushing and fatigue. No specific doses were mentioned. The video is essentially a community question: where do you inject and what else are you taking?
To be clear, this is anecdote-sharing, not medical advice-giving. She is not claiming GHK-Cu treats any condition, and she is not recommending anyone start it. That framing matters for how we evaluate the content.
Does the science back this up?
Yes, actually. Local injection site reactions with subcutaneous peptide administration are well-documented and not specific to GHK-Cu. The reactions she describes are consistent with what researchers call injection site reactions (ISRs), which can include erythema, pruritus, and induration.
GHK-Cu (copper tripeptide-1) has been studied primarily in wound healing, skin aging, and anti-inflammatory contexts. Pickart et al. (2015, Journal of Aging Science) reviewed GHK-Cu's biological activity extensively but that research was largely topical or in vitro. Human subcutaneous injection data is scarce because GHK-Cu is not an FDA-approved injectable drug. The absence of clinical trial data on subcutaneous injection tolerability is a real gap.
What we do know from broader peptide research: subcutaneous injections of bioactive peptides can cause localized histamine-like responses, particularly when the peptide has copper chelation activity. Copper itself is a known contact sensitizer (Rietschel and Fowler, 2008, Fisher's Contact Dermatitis). That mechanism could partially explain her reaction pattern, though no study has confirmed this specifically for injected GHK-Cu in humans.
What did they get wrong (or right)?
She got the symptom description right: what she is experiencing sounds like a genuine injection site reaction, not a sign she is injecting incorrectly. Rotating sites is the correct instinct and is consistent with standard subcutaneous injection guidance used in insulin and biologic therapy protocols.
Where the video falls short is in assuming that changing the injection site will resolve the reaction. If the reaction is driven by the peptide itself or its copper component, site rotation may reduce localized trauma but is unlikely to eliminate the immune-mediated response. She may be dealing with a sensitivity to the compound, not just poor technique or site fatigue.
Her NAD comment deserves a flag. Flushing and fatigue from NAD+ are common and dose-dependent side effects documented even in clinical settings (Elhassan et al., 2019, Cell Reports). But "I don't know if I need a different dose or whatever" is not a framework for adjusting a biologically active injectable. That kind of titration needs clinical supervision, not a TikTok comment section.
What should you actually know?
A few things worth knowing if you are following peptide therapy content online. First, GHK-Cu is not FDA-approved as an injectable drug. It is available as a research chemical or through compounding pharmacies in some jurisdictions, but compounded formulations are not equivalent to any approved drug and vary in purity and sterility. Second, consistent injection site reactions that look like "a bad bug bite" are worth telling a clinician about. They can indicate a sensitivity that may worsen over time.
Third, the TikTok peptide community frequently discusses stacking multiple peptides simultaneously, which is what the caption is soliciting. There is essentially no human safety data on most peptide combinations. What works for one person's goals and physiology may not translate to another's, and some combinations carry real risks that are not discussed in these formats.
If you are using injectable peptides, they should be prescribed and monitored by a licensed clinician who can assess your specific situation, not crowdsourced from social media.