Ksenia Petrushkina: Why are teenagers injecting peptides?

What happens when people start experimenting with peptides before seeing a clinician?

Ksenia Petrushkina sees the impact of peptides up close. As Director of Regenerative Medicine at Ideal Medical in Miami, she works with patients using peptides, longevity therapeutics, and regenerative medicine, including people who arrive after already starting protocols they found online. Before clinical medicine, Ksenia worked in cancer research. It taught her a lesson that still shapes how she thinks about peptides today: what looks extraordinary in a laboratory can fall apart completely in the real world. Now she sees the problem from the other direction. Patients arrive with gray-market vials, protocols copied from influencers, and stacks containing multiple experimental compounds. Some are teenagers. Ksenia is not anti-peptide. But she believes enthusiasm is moving faster than the evidence, and that separating promising biology from what is actually proven in humans will determine the future of peptide medicine. She explains:

■ Why teenagers are buying and injecting peptides they find online ■ Why she has serious reservations about MOTS-c and other heavily promoted compounds ■ Why promising results in petri dishes and mice can fall apart in humans ■ Why stacking multiple peptides makes benefits and side effects almost impossible to untangle ■ Why better safety data and real-world reporting could determine the future of peptide medicine Chapters

(00:00) - Intro

(01:52) - How Ksenia decides which peptides to use

(03:42) - Why Ksenia won’t recommend MOTS-c

(06:22) - The problem with gray-market peptides

(09:09) - What BPC-157 really tells us

(11:04) - Why peptide stacking makes no sense

(15:16) - Why doctors need better peptide data

(21:05) - How influencers distort peptide science

(23:20) - Why teenagers are injecting peptides

(26:20) - The future of peptide medicine

Watch the full episode on YouTube

Further reading

FDA: July 2026 Pharmacy Compounding Advisory Committee review covering BPC-157, TB-500, MOTS-c, and other peptide-related bulk substances: FDA PCAC July 2026 meeting

FDA: Current concerns around unapproved GLP-1 drugs, including retatrutide: FDA: Concerns with unapproved GLP-1 drugs

PubMed: Review of the safety, evidence, and regulatory status of approved and unapproved peptide therapies: Safety and Efficacy of Approved and Unapproved Peptide Therapies

PubMed: 2025 pilot study of intravenous BPC-157 in two human participants, discussed in the episode: Safety of Intravenous Infusion of BPC157 in Humans

Read the full transcript

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Instagram: @dr.kseniamiami Instagram: @kpmiami X: @drkseniamiami TikTok: @dr.ksenia.petrushkina305 Website: KseniaPetrushkina.com

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Peptide Show explores the science, medicine, business, and people shaping the rapidly evolving world of peptides. Presented by Longr: longr.io

Follow Peptide Show for new episodes every Tuesday. This podcast is for informational and educational purposes only and does not constitute medical advice. Some compounds discussed in this episode are investigational, unapproved for the uses discussed, or subject to changing regulatory requirements.