Cream versus pinning it, does the delivery method actually matter for GHK-Cu

It's not just vibes, it's a real bioavailability problem. Topical GHK-Cu sits in the skin and does its collagen/elastin thing locally, that's why it has actual human trials behind it, wrinkle depth studies, the diabetic ulcer trial with like a 98% closure rate versus 60% for the vehicle cream. Injectable is a totally different animal, the human data for that route basically doesn't exist. What you get is rat lung fibrosis papers and some neuro signaling stuff in animals. Interesting, not confirmed in people.

This matches what I found when I went down the rabbit hole last year. I made a little table (shocking, I know) comparing what each route claims to do. Topical: skin thickness, wrinkle depth, wound closure, all with real human numbers behind them. Injectable: theoretical systemic reach, zero human trials, just animal work and forum logs. I still run injectable for my elbows because cream physically cannot reach a tendon, but I stopped pretending the evidence is equivalent.

This is the right framing. Topical creates a depot right where you put it, it's not getting past the dermis into cartilage or a tendon sheath in any meaningful amount. If your goal is skin quality or a scar, topical is the correct tool and has the data to back it. If your goal is a tendon, you're relying on the idea that systemic delivery reaches the tissue, which is plausible but unconfirmed in humans.

So basically the cream is doing nothing for my patellar tendon no matter how much I rub in? That's kind of a bummer, I was hoping for the low effort option.

It was never going to be the low effort option for that. Tendons need load, GHK-Cu in any form is a side conversation. If you're going the injectable route for a knee I'd still want eccentric decline squats and isometrics doing the actual work.

One thing that doesn't get mentioned enough, injectable GHK-Cu means systemic copper exposure. Topical at normal concentrations isn't really a copper load concern, it stays local. Injecting regularly is a different pharmacokinetic situation and copper accumulation is a real thing to think about, not a hypothetical.

Wait so is anyone actually tracking copper levels while running this or is everyone just winging it

I get copper checked with my regular labs since I already do bloodwork for other stuff. Haven't seen it move much but I'm also not running it daily, more like a few times a week.

I use the cream on my scar from an old surgery and it looks noticeably better than the untreated side, so I believe in it for that. For my actual Achilles I never bothered with injectable, I just didn't feel comfortable operating that far outside any confirmed use case. Went the BPC-157 route for the tendon itself and used GHK-Cu for what it's actually proven to do.

That's basically where I've landed too. Keeping the cream for skin and scar work where I know it's earning its keep, and if I go injectable for the thumb I'm doing it with my eyes open that it's speculative, not proven.