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Side-by-side comparisons

Peptides are often sold as interchangeable when they are not. These pairs are the ones where the confusion is common and the difference actually matters.

Semaglutide vs Tirzepatide The two dominant weight-loss drugs. Different receptor targets, different outcome evidence. Evidence 5/5 vs 5/5 Tirzepatide vs Retatrutide An approved drug against the unapproved one with bigger phase 2 numbers. Evidence 5/5 vs 3/5 BPC-157 vs Pentadeca Arginate (PDA) The same peptide with a different counter-ion, sold as a regulatory workaround. Evidence 1/5 vs 1/5 Sermorelin vs CJC-1295 Pulsatile versus continuous growth hormone stimulation. Evidence 3/5 vs 2/5 Sermorelin vs Somatropin (recombinant hGH) Stimulating your own growth hormone versus replacing it outright. Evidence 3/5 vs 5/5 Gonadorelin vs Leuprolide Same receptor, opposite effect — dosing frequency reverses the outcome. Evidence 3/5 vs 5/5 Melanotan II vs Afamelanotide The unapproved tanning peptide against its approved, selective counterpart. Evidence 1/5 vs 5/5 Ipamorelin vs MK-677 (Ibutamoren) Injectable selective secretagogue versus the oral one with a heart failure signal. Evidence 2/5 vs 3/5 Linaclotide vs Plecanatide Two guanylate cyclase-C agonists with different pH behaviour. Evidence 5/5 vs 4/5 Vancomycin vs Daptomycin Two peptide antibiotics for MRSA — one works in the lung, one never can. Evidence 5/5 vs 5/5 GHK-Cu vs Palmitoyl Tripeptide-1 The same GHK sequence with two different delivery strategies. Evidence 3/5 vs 3/5 Thymosin Alpha-1 vs Thymalin A defined peptide with randomized trials versus an undefined extract. Evidence 4/5 vs 2/5 BPC-157 vs TB-500 / Thymosin Beta-4 The two most commonly stacked healing peptides, and what evidence each has. Evidence 1/5 vs 2/5 Larazotide Acetate vs BPC-157 The only "leaky gut" drug to reach phase 3, against the one that never ran a trial. Evidence 3/5 vs 1/5 MOTS-c vs Elamipretide (SS-31) Two mitochondrial peptides at opposite ends of the evidence scale. Evidence 1/5 vs 4/5 PT-141 (Bremelanotide) vs Melanotan II The approved melanocortin drug and the compound it was derived from. Evidence 5/5 vs 1/5

Compare any two Any pair works: /compare/<first-slug>-vs-<second-slug>. For example /compare/semaglutide-vs-liraglutide.