Content reviewed by clinical research staff

Last reviewed: March 2026Sources: PubMed, FDA, WADA Prohibited List

Evidence graded using the PeptideScholar A-D system

Thymalin

CPreclinical

Thymic dipeptide · 2 amino acids

Not FDA ApprovedWADA Banned

Thymalin is a synthetic dipeptide (glutamyl-tryptophan) originally derived from calf thymus extract. Developed by Vladimir Khavinson in Russia, it is used there for immune modulation.

Mechanism of Action

Modulates T-cell differentiation and function. Restores thymic function in aged subjects. Regulates cytokine production and immune cell ratios.

Benefits

  • Immune system restoration in elderly patients (Russian studies)
  • Increased T-cell counts in immunocompromised subjects
  • Extended lifespan in animal aging studies
  • Approved and clinically used in Russia
Not Medical Advice — Research-Reported Information Only

This content is for informational purposes only and does not constitute medical advice.

Thymalin — Dosing in Published Research

Reported Routes: Intramuscular injection, Subcutaneous injection
Russian clinical protocols use 10 mg IM daily for 5-10 days. Typically administered in courses 1-2 times per year.

The dosing information above is sourced from published research literature and clinical trials. These are not recommendations. Individual responses vary. Always consult a healthcare provider before considering any peptide-based therapy.

Side Effects

  • Generally well-tolerated in Russian clinical use
  • Mild allergic reactions reported rarely
  • Injection site reactions
  • Limited Western safety data

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Thymalin is not FDA-approved. Always consult a licensed healthcare provider before considering any peptide.

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Research & Evidence

CohortBulletin of Experimental Biology and Medicine, 2003

Peptide regulation of aging: 35-year research experience

Long-term thymalin administration reduced mortality by 2-fold in elderly subjects over 6-year follow-up (Russian study)

PMID: 12937225
CohortAdvances in Gerontology, 2008

Peptide bioregulators and immune function

Thymalin restored age-related decline in T-cell immunity and normalized cytokine profiles in elderly patients

PMID: 18374557

Compare Thymalin With

References

  1. 1. Peptide regulation of aging: 35-year research experience. Bulletin of Experimental Biology and Medicine, 2003. Long-term thymalin administration reduced mortality by 2-fold in elderly subjects over 6-year follow-up (Russian study) [PMID: 12937225]
  2. 2. Peptide bioregulators and immune function. Advances in Gerontology, 2008. Thymalin restored age-related decline in T-cell immunity and normalized cytokine profiles in elderly patients [PMID: 18374557]

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Medical Disclaimer

This content is for informational and educational purposes only and does not constitute medical advice, diagnosis, or treatment recommendations.

Always consult a qualified healthcare provider before starting, stopping, or modifying any treatment. Do not disregard professional medical advice based on information found on this site.

No claims of therapeutic efficacy are made for substances that are not FDA-approved for the discussed indications. Research citations reflect published findings and do not imply endorsement.

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