Peptide stacking safety — combining multiple research peptides

We get questions about peptide stacking every day, so I'm creating this reference thread. The most common stack our members use is GLP-1 RA + BPC-157 + TB-500. Let's discuss the safety considerations systematically. The fundamental question: are there dangerous interactions between these peptides? Short answer: no known dangerous pharmacological interactions. But "no known interactions" is different from "proven safe in combination," and I want to be transparent about what we know and don't know. What we know: 1. GLP-1 RAs (semaglutide, tirzepatide) work through incretin receptors — GLP-1R and GIP-R. These are G-protein coupled receptors primarily in the pancreas, gut, and CNS. 2. BPC-157 works through multiple pathways: nitric oxide system, FAK-paxillin signaling, VEGF upregulation, and dopamine/serotonin modulation. It does NOT interact with incretin receptors. 3. TB-500 works through intracellular actin regulation, promoting cell migration and angiogenesis. It does NOT interact with incretin or nitric oxide pathways significantly. These three peptides act through distinct, non-overlapping receptor systems. There's no known receptor competition, metabolic interference, or pharmacokinetic interaction between them. What we DON'T know: 1. No formal drug interaction studies have been conducted between any of these compounds 2. Downstream signaling convergence is possible but unstudied — for example, both GLP-1 and BPC-157 affect inflammatory pathways, so additive anti-inflammatory effects are possible (probably beneficial but unmeasured) 3. Long-term safety of any combination beyond anecdotal reports does not exist 4. Individual genetic variation in metabolism could create unexpected interactions I want members to share their stacking protocols and any adverse events (or lack thereof) to build our collective knowledge base.