#03 Where to Get Peptides: Sourcing, Compounding & Gray Markets

Dr. Rehan Muttalib and Milan Costich get into what happens after the GLP-1. Milan asks the question most people land on eventually: if these drugs cost you muscle along with the fat, is there a way to lose one and keep the other? That opens up stacking, and the single rule Dr. Rehan says matters most, which is never running two peptides that bind the same receptor. He walks through growth hormone secretagogues (sermorelin, CJC-1295, tesamorelin), why he'd reach for those long before anyone touches exogenous growth hormone, what cycling on and off actually looks like, and why the worst-case outcome with peptides is returning to baseline rather than ending up worse than you started.

From there they get into the part nobody wants to say out loud: where people are actually buying this stuff. Dr. Rehan is candid about the gray market, the "research purposes only" loophole, and why the same website can send you two completely different vials a month apart. He explains what he tells patients who admit they're buying that way, what a 503A or 503B compounding pharmacy changes, and how to check whether one is regulated. The last stretch covers the mitochondrial pathway and NAD+, why "calories in, calories out" stopped satisfying him as an explanation for the patients in front of him, whether a GLP-1 should be cycled at all, and what the next generation of these compounds is going to look like.

This episode is for educational purposes only and is not medical advice. Talk to your own physician before starting or changing any treatment.

00:00 Intro

01:51 What "stacking" means, and the one rule that matters

04:15 How many people are actually on a GLP-1

07:10 Why growth hormone has such a bad reputation

11:25 What a growth hormone secretagogue actually does

13:59 Body recomposition and muscle as longevity currency

18:45 Sermorelin, CJC-1295, and tesamorelin

24:54 Cycling on and off, and what happens when you stop

28:47 A word from our sponsor

29:28 Where to start, and how GHRPs stack

31:50 Sourcing peptides and the gray market

36:05 503A and 503B pharmacies

39:13 Adding a third peptide, and when weight loss stalls

42:27 The mitochondrial pathway

47:05 NAD+: IV, injectable, and nasal spray

51:04 Should you cycle a GLP-1?

53:32 What's coming next in this drug class

55:30 Why this is so hard to navigate alone

Every week, Physician Dr. Rehan Muttalib and XYRx founder Milan Costich on the real science of male longevity: peptides, GLP-1s, training, and recovery.

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