The PepStack Pro Blog

Physician-written articles on peptides, protocols, FDA updates, and longevity medicine. No hype — just science and clinical experience.

14 min readGLP-1SemaglutideTirzepatideRetatrutideWeight LossLongevity

The Physician's Guide to GLP-1 Medications: Semaglutide vs. Tirzepatide vs. Retatrutide

GLP-1 medications are the biggest breakthrough in metabolic medicine since statins. A physician's no-nonsense guide to how they work, how they compare, side effects to expect, and why supervision matters more than which one you choose.

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12 min readPeptidesStackingProtocolsLongevityGuide

The Complete Beginner's Guide to Peptide Stacking: Rules, Proven Combos, and What to Avoid

Peptide stacking is one of the most powerful tools in longevity medicine — and one of the most misunderstood. A physician's no-nonsense guide to the 4 rules of smart stacking, 5 proven combinations by goal, and the mistakes that waste your money.

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10 min readSafetyGray MarketPeptidesLongevity

Gray Market vs. Physician-Supervised Peptides: What You Need to Know

The peptide market is booming — and so are unregulated sources. A physician's honest breakdown of the real risks of gray-market peptides, what supervised therapy actually looks like, and why the cost comparison isn't what you think.

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8 min readFDARegulationBPC-157Peptides

FDA Peptide Reclassification 2026: 14 Peptides Restored — What It Means for You

On February 27, 2026, HHS announced that 14 previously restricted Category 2 peptides are moving back to Category 1. Here's what changed, which peptides are affected, and what this means for your protocols.

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