Last updated October 21, 2026. Approval line checked October 21, 2026. No compounding source date is assigned.
FDA status
Not approved
Not approved. This record is not an FDA-approved drug product. Approval, where it exists, is specific to a drug product, indication, and route.
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Evidence tier
Human Observational. The tier is the highest indexed study type. It is not a safety rating and it is not an FDA approval. Confidence score 3/5. 839 PubMed citations indexed.
Thymulin is a naturally occurring nonapeptide (H-Pyr-Ala-Lys-Ser-Gln-Gly-Gly-Ser-Asn-OH) secreted by thymic epithelial cells that requires chelated zinc for biological activity; it promotes T-cell dif
What the literature studies
Immune Research
Evidence tier
Human Observational
Compounding record
Status not verified
Status not verified. No product-specific FDA primary source is recorded for this entry. FDA approval and compounding eligibility are not verified. Research information is not evidence of FDA approval. Approval, where applicable, is specific to a drug product, indication and route. Research information is not evidence of FDA approval. Approval, where applicable, is specific to a drug product, indication and route.
Regulatory source not verified; no checked date is assigned.
Thymulin levels decline sharply after age 60 and zinc deficiency abrogates activity; without zinc co-supplementation renders the peptide biologically inactive.
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Educational only. Not medical advice. This page does not give doses or sourcing. See the medical and editorial disclaimer.