u/Clinpep

ok so context. ive been researching peptides for years between personal use and the people around me, and the reference situation drove me insane. you want trial dosing, you go to pubmed. you want contraindications, different paper. you want to know what the FDA actually says, third place. you want interactions or stacking data, basically nowhere coherent. most people end up trusting whatever their vendor or some forum post told them because pulling the actual literature for every compound takes hours nobody has.

so i built one. its called clinpep. 60+ peptides in it right now with mechanism, trial protocols, contraindications, interactions, citations to the actual primary sources. free. no signup wall, no email capture, no upsell. you just use it.
its at the point where i need real users banging on it to figure out whats actually missing or unclear versus what i think is fine because im too close to it. specifically.

which compounds people search for that arent in there yet. ive got my next list but its partly guesswork at this point.

whether each entry is organized in a way that makes sense to someone who didnt build it. stuff i think is clear may not be.

what data fields would matter that arent in there. interactions are thin in some entries. compounding stability is light. half life is in some entries and not others. open to whats missing.

whether the depth is right. some people want the trial citations, some people want a one paragraph summary. trying to figure out where the balance is.
if you spend any time researching peptides and want to take a look, the name is clinpep. takes 30 seconds to see if its useful for you. happy to dm with anyone who has detailed feedback or wants compounds added.

not selling anything. free is free. just trying to build something in this space that doesnt suck.

The peptide world loves to talk about “GH optimization” through GHRH and GHRP stacks. Those are tools that work with your endogenous system. Actual recombinant HGH (somatropin) is a different category entirely and the risk profile reflects that.

Endogenous GH release is pulsatile. Your pituitary fires off bursts, mostly at night during deep sleep, and your liver converts that to IGF-1 over the following hours. GHRH/GHRP stacks try to enhance this natural pattern. They have a ceiling because your own pituitary has a ceiling.
Exogenous HGH bypasses all of that. You inject somatropin, you get sustained elevated GH levels, your IGF-1 climbs to whatever the dose dictates. There’s no negative feedback loop the way there is with endogenous release. This is why HGH works so well and also why it’s risky.

The benefits people chase are real: body composition changes, recovery, skin and connective tissue effects, sleep quality at lower doses. The trade-offs are also real. Insulin resistance is the big one — GH is fundamentally diabetogenic, and chronic supraphysiological GH levels move people toward glucose dysregulation. Joint pain, water retention, carpal tunnel, and edema show up at higher doses. The long-term cancer signal in supraphysiological use is debated but not zero.

Dosing reality check: TRT-equivalent HGH dosing for adults with documented deficiency is 1-2 IU daily. Anti-aging clinic doses are often 2-4 IU daily. Bodybuilding doses are 4-10+ IU daily and that’s where the side effects start mattering a lot. People dose based on the goal they want, not the dose their physiology can actually handle.

If you’re considering HGH, get IGF-1 baseline, A1c baseline, and fasting insulin baseline. Then re-test at 3 months. If your fasting insulin is climbing fast, your dose is too high regardless of how good the body comp looks.

The other thing nobody mentions: HGH is one of the most counterfeited compounds on the gray market. If you’re not getting it from a legitimate source, you have no idea what’s in the vial.

A lot of “HGH” out there is underdosed, mislabeled, or just GH-releasing peptides repackaged.

The peptide world loves to talk about “GH optimization” through GHRH and GHRP stacks. Those are tools that work with your endogenous system. Actual recombinant HGH (somatropin) is a different category entirely and the risk profile reflects that.

Endogenous GH release is pulsatile. Your pituitary fires off bursts, mostly at night during deep sleep, and your liver converts that to IGF-1 over the following hours. GHRH/GHRP stacks try to enhance this natural pattern. They have a ceiling because your own pituitary has a ceiling.

Exogenous HGH bypasses all of that. You inject somatropin, you get sustained elevated GH levels, your IGF-1 climbs to whatever the dose dictates. There’s no negative feedback loop the way there is with endogenous release. This is why HGH works so well and also why it’s risky.

The benefits people chase are real: body composition changes, recovery, skin and connective tissue effects, sleep quality at lower doses. The trade-offs are also real. Insulin resistance is the big one — GH is fundamentally diabetogenic, and chronic supraphysiological GH levels move people toward glucose dysregulation. Joint pain, water retention, carpal tunnel, and edema show up at higher doses. The long-term cancer signal in supraphysiological use is debated but not zero.

Dosing reality check: TRT-equivalent HGH dosing for adults with documented deficiency is 1-2 IU daily. Anti-aging clinic doses are often 2-4 IU daily. Bodybuilding doses are 4-10+ IU daily and that’s where the side effects start mattering a lot. People dose based on the goal they want, not the dose their physiology can actually handle.

If you’re considering HGH, get IGF-1 baseline, A1c baseline, and fasting insulin baseline. Then re-test at 3 months. If your fasting insulin is climbing fast, your dose is too high regardless of how good the body comp looks.

The other thing nobody mentions: HGH is one of the most counterfeited compounds on the gray market. If you’re not getting it from a legitimate source, you have no idea what’s in the vial.

A lot of “HGH” out there is underdosed, mislabeled, or just GH-releasing peptides repackaged.

BPC-157 is a synthetic fragment derived from a protein found in gastric juice. The preclinical research is genuinely impressive across tendon healing, gastrointestinal healing, vascular effects, and neuroprotection. The catch is that most of that research is in rats. Human clinical trial data is almost nonexistent. WADA has it on the prohibited list. The FDA has flagged it. None of that proves the compound doesn’t work. It means the evidence base is what it is.

The mechanism people cite from the preclinical literature is angiogenesis promotion and growth factor upregulation at injury sites. The reason informal use has continued growing despite the thin human research is that the user reports are remarkably consistent for specific use cases. Tendon and joint issues that aren’t healing on their own. Gut inflammation. Sub-acute soft tissue injuries stuck in inflammatory loops.

When a compound has thin clinical data but consistent anecdotal results across thousands of users for a specific use case over more than a decade, that’s a different epistemic situation than either pure science or pure folklore. It’s worth something even if it isn’t proof.

Where the hype overruns the research. BPC isn’t going to fix structural problems. Torn tendons that need surgical repair still need surgical repair. Bone-on-bone joint damage isn’t getting regenerated. The realistic claim sits in a narrow lane around soft tissue healing acceleration. Within that lane the signal is strong enough that there’s probably something real there. Outside it, the marketing is doing more work than the biology.

The thing nobody quite says out loud. BPC has been in widespread informal use for over a decade. If it produced obvious harm at typical exposure ranges, the signal would have shown up by now. The absence of obvious harm is not the same as a real safety profile, but it’s also not nothing. We have years of n-of-many informal use without dramatic adverse signal. That’s the actual evidence picture.

Probably the most interesting unresolved peptide in the space right now. The reasons it’s unresolved are part of what makes it interesting.

Ipamorelin gets recommended as the entry-level GH peptide and there’s a real reason. It’s the most selective GHRP in the literature. Minimal cortisol release, minimal prolactin release, minimal hunger effects compared to GHRP-2 or hexarelin. The selectivity is the point.

The flip side of selectivity is potency. Ipamorelin produces a smaller GH pulse than the less selective GHRPs. That’s the actual trade-off. You’re trading magnitude for a cleaner signal.
Where this gets interesting is the stacking research. GHRP alone is one kind of stimulus. GHRH alone is another. The two combined produce synergistic GH release that exceeds either alone. The literature on this is pretty consistent. Ipamorelin run solo is doing one job. Ipamorelin paired with a GHRH like Mod GRF 1-29 is doing a coordinated job that maps better to physiological release patterns.

The timing piece is also in the literature. Endogenous GH release peaks during slow wave sleep. Administration aligned with that window produces different effects than midday administration. The pituitary is more responsive at certain points in the circadian rhythm. The research has been pretty clear about this for a long time and the informal protocols tend to reflect it.

One signal that something is off with sourcing. The selectivity profile is the defining feature of ipamorelin. If a product is producing hunger, head rushes, or flushing effects, the molecule isn’t behaving like ipamorelin. That points to either a different GHRP, contamination, or a misidentified compound.

Useful tool with a narrow purpose. Most disappointment with it comes from running it outside the context it was studied in.

CJC-1295 exists in two forms and they behave like different drugs.

Mod GRF 1-29, which is CJC without DAC, is a short-acting GHRH analog. The half-life is short. Administration produces a discrete GH pulse, then it’s over. This mirrors the way endogenous GH release actually works physiologically. The pituitary fires in pulses, your liver converts that to IGF-1 over hours, the system resets, and the cycle repeats.

CJC-1295 with DAC is a different molecule. DAC stands for drug affinity complex, which binds the peptide to albumin and extends the half-life to roughly a week. Instead of pulses you get sustained elevated GH and IGF-1. That sounds better on paper. It isn’t necessarily better in practice.

The reason pulses matter is that GH receptors downregulate under continuous stimulation. The receptor system evolved to respond to waves. Sustained tonic exposure changes the response profile. CJC with DAC essentially converts your endogenous system into a low-dose continuous HGH exposure with different effects, different side effect signal, and different long-term implications than pulsatile use.

The research on physiological GH release strongly supports pulsatility. The research on chronic tonic GH elevation looks more like the somatropin literature than the GHRH analog literature.

Functionally those are different compounds even if the marketing groups them together.

Worth understanding which version is being discussed in any conversation about CJC-1295, because the answer changes everything downstream.

The stacking conversation tends to be additive. People ask “what should I add” rather than “what shouldn’t be in the same protocol.”
Three examples worth thinking about.

Multiple GHRPs at once. Ipamorelin plus GHRP-2 plus hexarelin doesn’t produce additive GH pulses. It produces receptor desensitization. The research on tachyphylaxis with ghrelin receptor agonists has been around for a while and informal protocols routinely ignore it.

GHRH analogs running alongside exogenous HGH. The pituitary stimulation is doing nothing because the negative feedback loop has been broken by the exogenous GH. Spending money on Mod GRF while running somatropin is essentially paying for a placebo.

PT-141 stacked with anything else that affects blood pressure. The mild BP effects of PT-141 alone are manageable. Stacked with stimulants, with certain pre-workouts, with other vasoactive compounds, the combination produces signal that wasn’t in the original safety profile.

What other combinations are getting underdiscussed.

quick intro post since the sub is new and people are starting to find it.

clinpep is a clinical peptide reference platform. clinpep.com if you want to look. its free. were building it because the reference situation in peptides is genuinely a mess and somebody needed to fix it.

heres the problem we kept running into. half the dosing and protocol info circulating online comes from sales reps. the other half is forum posts copying other forum posts copying something somebody said in a podcast. the actual primary literature exists but its scattered across pubmed, clinicaltrials.gov, fda filings, and journal paywalls. nobody has time to pull all of that for every compound theyre trying to understand.

so we did the pulling. 45 peptides so far with full clinical data, mechanism, trial protocols, contraindications, interactions, citations to the actual sources. its not opinion, its not marketing, its what the literature says with links back to where it came from. when someone googles a peptide they should land on something written from the data instead of something written to sell them a vial.

what this sub is for. discussion thats actually grounded in the research. mechanism questions, trial data questions, “this compound is being marketed this way but the evidence looks like that” type conversations. clinic staff, prescribers, compounders, informed users, anyone who wants to think about peptides without the marketing layer on top.

what its not for. sourcing requests. “is this legit” vial photos. recreational dosing advice. theres other subs for all of that and theyre fine for what they do, just not what were building here.
rules are in the sidebar. read them before posting.
if youve got compounds you want us to add to the platform, data fields that would be useful, or feedback on whats already there, drop it in the comments or dm.

were actively building this and outside input is most of how it gets better.
glad youre here.

Peptides get evaluated on cost per dose. Cost per cycle. Cost per outcome people are hoping for. The conversation rarely asks what should probably be the first question, which is how much human research actually supports the compound being used.

A rough map of where the human evidence sits.
Compounds with substantial human trial data. The GLP-1 receptor agonists. Tesamorelin in its specific indication. HCG for fertility and cosmetic preservation. Somatropin for documented deficiency.

Compounds with moderate human research, mostly in narrow indications. PT-141 / bremelanotide. Some GHRP literature.
Compounds with thin human research and substantial preclinical data. BPC-157. TB-500.

Most of the “regenerative” peptide category.
Compounds with essentially no human research where the marketing is doing all the work. A lot of the longevity-positioned peptides. A surprising amount of what gets sold as “research chemicals.”

The implication isn’t that thin-evidence compounds are useless. It’s that the price you pay should reflect what you actually know about what the compound does. Paying premium prices for compounds with mouse data and good vibes is a different transaction than paying premium prices for compounds with phase 3 trials.

Where does the price-to-evidence ratio actually break down in this space.

NAD+ is having a moment and most of the conversation is downstream of marketing rather than data.

The mechanism is real. NAD+ is a coenzyme involved in basically every energy-producing reaction your cells run. Levels decline with age. Restoring them in model organisms produces a range of effects from improved mitochondrial function to lifespan extension in some species. That’s the foundation everyone is building the hype on.

Where the gap shows up. The mouse data is impressive and the human data is thin. Oral precursors like NR and NMN reliably raise blood NAD+ levels in humans. Whether that translates to the clinical benefits people are paying for is genuinely unknown. The trials that exist are small, short, and use soft endpoints. The big longevity claims are extrapolation, not measurement.

Injectable NAD+ is a different category and the pharmacokinetics are weird. The infusions are notoriously uncomfortable, with chest pressure and a flushed feeling that isn’t subtle. The dose response data for any specific outcome basically doesn’t exist in human literature. Clinics charging premium prices for IV protocols are selling something the evidence hasn’t actually established at those prices.

The compound is interesting. The science around NAD+ biology is moving. The clinical pitch has run way ahead of where the data sits. Both can be true.

The tesamorelin conversation tends to collapse into “GH peptide for fat loss” and that flattens what the actual research shows.

The registration trials werent run for general weight loss. They were run in HIV-associated lipodystrophy, where visceral adipose tissue had become a clinical problem. Within that population the visceral fat reduction was substantial and statistically robust. Subcutaneous fat barely moved. That distinction matters and gets lost constantly.

Mechanism wise tesamorelin is a stabilized GHRH analog. It triggers endogenous GH release through the pituitary, which means the response is still subject to negative feedback. Thats different from exogenous HGH where the feedback loop is bypassed. The pulsatility of release is closer to physiological than what you get from somatropin.

The trial protocol matters too. Daily dosing, evening administration, fasted state. Sub-trial-protocol use shows weaker signal in the data, which is one reason a lot of informal use reports underwhelming results. The molecule was studied a specific way and the outcome data reflects that specific way.

IGF-1 goes up. Thats the mechanism working. The trials tracked IGF-1, fasting glucose, and insulin sensitivity because GH activity affects glucose handling. Any serious discussion of the compound has to include that monitoring picture, not just the visceral fat number.

The other thing worth flagging is cost. Legitimate tesamorelin is one of the more expensive peptides in this space. The trial population had a clinical indication that justified that cost. Extrapolating to recreational visceral fat reduction is a different cost-benefit calculation entirely.

Useful compound with a narrow evidence base. The narrowness is the point.

Ipamorelin gets recommended constantly as the “beginner GH peptide” and there’s a reason — it’s the most selective GHRP available. Minimal cortisol release, minimal prolactin release, minimal hunger effects compared to GHRP-6 or even GHRP-2. The selectivity is real.

The flip side of selectivity is potency. Ipamorelin produces a smaller GH pulse than GHRP-2 or hexarelin. That’s the trade-off. You’re trading magnitude for a cleaner side effect profile.

Where this matters: if you’re stacking with a GHRH like Mod GRF 1-29, the synergy is what does the work. The GHRH primes the pituitary, the GHRP triggers the pulse. Ipamorelin alone is a polite knock on the door. Ipamorelin with a GHRH is a coordinated release. People running ipamorelin solo and reporting “I felt nothing” are usually running it without the GHRH and at sub-therapeutic doses.

Standard dosing that actually does something: 200-300mcg, 2-3x daily, with Mod GRF 1-29 at matched doses. Before bed is non-negotiable because that aligns with your natural GH pulse. The middle-of-day dose is optional and largely about how committed you are to pinning three times a day.

One thing to watch: if you’re feeling significant hunger, head rushes, or flushing, you probably got something that isn’t pure ipamorelin. The selectivity profile is the whole point. If you’re getting GHRP-6 type effects from your ipamorelin, your sourcing is the problem.

Quick primer because this one’s coming fast. Semaglutide is GLP-1 only. Tirzepatide is GLP-1 plus GIP. Retatrutide is GLP-1 plus GIP plus glucagon. Triple agonist. The Phase 2 data showed something like 24% weight loss at 48 weeks, which is closer to bariatric surgery territory than traditional pharmacotherapy.

That’s the headline. Here’s the part nobody’s talking about yet.

The glucagon arm is what’s driving the additional weight loss beyond what tirz does, and glucagon agonism does a lot of things at once. It increases energy expenditure, which is great. It also affects hepatic glucose output and has real implications for people with any insulin resistance or fatty liver.

The trial data is encouraging on liver fat actually decreasing, but the long-term metabolic profile in a broader population is genuinely unknown.
Side effect profile in the trials was the usual GLP-1 stuff — nausea, GI issues, the same family of problems. Cardiovascular signals so far look fine but the trials aren’t big enough yet to call it.

The reta gray market is already huge. People are running it before there’s any real-world experience to draw on. We’re going to learn a lot about this molecule the hard way over the next two years.

If you’re going to use it anyway, the dosing people are converging on is much lower than what trials used — 2-4mg weekly versus 12mg in the trials — because the side effects at trial doses are rough.

Lower dose, slower titration, full bloodwork including lipids and liver enzymes, and treat it like the experimental drug it currently is.

This molecule is going to be huge. It’s also going to generate a lot of stories.

Most peptides, the conversation is about subq dosing. GHK-Cu is the opposite — most of the real data is topical and people keep trying to inject it like it’s BPC.

GHK-Cu is a copper-binding tripeptide. Your body makes it. Levels drop hard with age. It’s been studied for wound healing, skin remodeling, and hair follicle signaling since the 80s, which is ancient history in peptide world.

Topical GHK-Cu has decent data for skin — collagen synthesis, wound healing, some hair density signals when combined with microneedling. It’s in a lot of high-end skincare for a reason. The mechanism on hair is interesting because it seems to work through pathways that don’t overlap with minoxidil or finasteride, which is why people stack it.

Injectable GHK-Cu is where things get fuzzy. The systemic data is mostly preclinical. People inject it for “systemic anti-aging” but you’re basically extrapolating from skin and wound healing studies and hoping it does something useful in the rest of the body.

If you’re using it for hair or skin, topical with microneedling is where the evidence actually sits. If you’re injecting it expecting it to do something magical to your whole body, you’re paying for a story the data hasn’t told yet.

One annoying detail: copper peptides oxidize. If your GHK-Cu solution isn’t deep blue, something is off. If it’s clear, it’s degraded or it wasn’t compounded right to begin with.

Been seeing this come up a lot lately so figured I’d write it out.

Quick mechanism refresher: HCG mimics LH. Your testes don’t care about your serum T number — they care about LH telling them to keep producing intratesticular testosterone. That ITT is what actually drives sperm production. When you go on TRT, your LH crashes, ITT crashes with it, and spermatogenesis goes with it. HCG keeps the Leydig cells doing their job through all that.
Fine, everyone knows this part. The part nobody talks about is the dose.

Coviello’s 2005 study got 250 IU every other day to restore ITT in suppressed men. That’s where the “you don’t need much” idea comes from. Hsieh in 2013 used 500 IU twice weekly and preserved actual sperm parameters in guys on TRT — that one’s the more relevant trial if your goal is fertility, not just lab values.

Rough picture of where the evidence sits:
Under 500 IU/week, you’re basically checking a box. Not nothing, but not what the fertility trials used. 500 to 1500 a week split into two or three shots is where most of the real preservation data lives. Above 2000 you’re getting diminishing returns and a lot more aromatization, which means more estrogen problems for not much more benefit.

Here’s where it gets annoying. A lot of clinics put guys on 200 IU twice a week and call it a fertility protocol. That’s below the threshold of basically every study that actually tracked sperm parameters. It might keep your balls from shrinking, which is fine if that’s the goal, but those are two different goals and they need different doses. Cosmetic preservation and actual fertility preservation are not the same conversation.
The only way to know it’s working for you specifically is a semen analysis. Baseline before you start, follow-up at 3-6 months. Otherwise you’re guessing and your clinic is guessing with you.

Seeing this conflation constantly and it leads people to make bad decisions about switching.
Semaglutide is a pure GLP-1 agonist. Tirzepatide is a dual GIP/GLP-1 agonist. Different mechanism, not just a stronger version of the same thing. The trial data reflects that.
Head-to-head, roughly:
• Weight loss: SURMOUNT-1 (tirz) showed ~21% mean reduction at 72 weeks. STEP-1 (sema) showed ~15% over a similar timeframe. Different trials, comparable populations.
• A1c reduction: Tirz outperforms sema in direct head-to-head (SURPASS-2).
• GI side effects: Broadly similar profiles. Some signals of less nausea on tirz, but nothing definitive.
• Lean mass loss: Both cause meaningful lean mass loss. Tirz looks slightly better in body comp data, but not by a margin that should make anyone skip resistance training and protein.
• Cost: Tirz is typically more expensive, especially out-of-pocket.
Where people get this wrong: they see “21% vs 15%” and assume tirz is just the upgrade. But more weight loss isn’t automatically the right answer for you. If you tolerate sema, are hitting your goals, and the cost works — switching for an extra few percentage points on paper is often a bad trade.
The GIP component is genuinely different pharmacology. It’s not a dose increase. Worth understanding what you’re actually taking and why before swapping.

If you’ve been hitting the same belly spot for 6 months, you’re not absorbing what you think you are.
Repeated injections in the same site cause lipohypertrophy — fibrotic, vascular-poor tissue that absorbs peptides erratically. The tissue gets thick, scarred, and underperfused. Insulin users have known this for decades. The peptide world is just catching up.
This is the #1 reason people swear their dose “stopped working” and start chasing higher mg. The peptide is fine. The site isn’t.
Four rules I follow:
1. Rotate across at least 4 zones — abdomen quadrants, outer thighs, deltoids, glutes. Treat each zone like its own grid.
2. Each shot at least 1 inch from the last. Map it if you have to. Most people think they’re rotating and are actually hitting a 2cm radius.
3. Different zones for different molecules. GLP-1 in one quadrant, BPC in another, GH peptides somewhere else. Keeps your stack legible and lets you actually tell what’s doing what.
4. If you can pinch a hard or rubbery spot, retire that site for 60+ days. That tissue needs to remodel before it’ll absorb properly again.
If your results plateaued and you haven’t audited your injection sites, audit them before you touch your dose.