Thymolin
Also known as: Thymic peptide complex
Thymolin (also called Thymic peptide complex) is a thymic peptide. Thymolin is marketed as a thymic immunomodulator, but the name is not an international nonproprietary name and does not map to one defined molecule; material sold under it may be a thymic extract, a synthetic fragment, or a preparation closely related to Thymalin.
For research use only.
Key Facts
- CAS
- —
- Molecular Weight (MW)
- —
- Half-life
- Not established
- FDA status
- Not Approved
- Administration Route
- Subcutaneous
- Frequency
- —
- Last updated
- Aug 30, 2026
- Reviewed
- Aug 30, 2026
- Targets
- Thymic immune signaling (claimed)
Research summary
Vendor thymic-immune peptide listing; identity may overlap thymulin/thymogen/thymalin depending on supplier. Not FDA-approved.
Peptide Library's Thymolin profile summarises 5 cited studies listed in the Science section, the compound's regulatory status, and research-protocol parameters reported for it. It is a research reference, not medical advice.
Protocol
- Dosage Range
- —
- Frequency
- —
- Cycle
- —
- Administration Route
- Subcutaneous
- Reconstitution Guide
- —
- Injection Sites
- Abdomen
- Timing Notes
- Prefer injectable forms; oral versions generally have low bioavailability and are not recommended.
Not yet checked against primary sources
These figures are compiled from earlier reference material. They have not been verified against FDA labelling, registered trials or published literature, no citation is attached to them, and none of them is a recommended dose. Thymolin is queued for dosage evidence review.
Compare reported doses across the whole librarySequence & molecular data
| Half-life | Not established |
|---|---|
| Appearance | White lyophilized powder |
| Formulation | Lyophilized Powder |
Identifiers link to the public PubChem, FDA Substance Registration (UNII), ChEMBL and DrugBank records for the same entity.
Science
Mechanism of Action
Thymolin is marketed as a thymic immunomodulator, but the name is not an international nonproprietary name and does not map to one defined molecule; material sold under it may be a thymic extract, a synthetic fragment, or a preparation closely related to Thymalin. That ambiguity is the most important thing a reference can say about it, and the certificate of analysis should be checked to establish what a given product actually contains. Where the material is a thymic peptide preparation, the proposed activity is support of T-cell differentiation and maturation analogous to endogenous thymic hormones. There is no controlled human efficacy evidence for the named product.
Origin
Commercial thymic peptide label.
Targets
Regulatory & research status
Thymolin is not an FDA-approved product. It is sold for laboratory research and has no approved medical use.
| FDA status | Not Approved |
|---|---|
| Availability | Research-Only |
| WADA (sport) | Unknown / Not Listed |
| Library classification | Research-Only |
Benefits
Thymolin side effects
Side Effects
- Unknown / product-dependent
Storage & stability
Lyophilized (freeze-dried) peptide powder is far more stable than the reconstituted solution. Keep sealed vials cold, dry and away from light; long-term storage is typically frozen, with short-term refrigeration for vials in use.
Once reconstituted in bacteriostatic water, keep the solution refrigerated, avoid repeated freeze–thaw cycles and agitation, and label the vial with the reconstitution date and concentration. Discard any solution that turns cloudy or shows particulates.
Degradation rates differ by sequence: peptides containing methionine, cysteine, asparagine or glutamine are more prone to oxidation and deamidation, so shelf life after reconstitution is compound-specific rather than universal.
Read the full guide: how to store peptides before and after reconstitution →
Source: Manning MC, Chou DK, Murphy BM, Payne RW, Katayama DS. Stability of protein pharmaceuticals: an update. Pharm Res. 2010;27(4):544–575. (PMID 20143256). General guidance for research handling; not product-specific instructions.
Thymolin: frequently asked questions
What is Thymolin?
Vendor thymic-immune peptide listing; identity may overlap thymulin/thymogen/thymalin depending on supplier. Not FDA-approved.
How does Thymolin work?
Thymolin is marketed as a thymic immunomodulator, but the name is not an international nonproprietary name and does not map to one defined molecule; material sold under it may be a thymic extract, a synthetic fragment, or a preparation closely related to Thymalin. That ambiguity is the most important thing a reference can say about it, and the certificate of analysis should be checked to establish what a given product actually contains.
Is Thymolin FDA approved?
No. Thymolin is not approved by the FDA for any indication and is categorised as research-only. It has not been reviewed for safety or efficacy as a medicine, and published research should be read as investigation rather than established use.
What peptides are similar to Thymolin?
Compounds most often compared with Thymolin include Thymosin Alpha-1, Thymalin, Thymogen (Oglufanide) and Thymopentin. They are grouped by shared mechanism or research area rather than by equivalence, and their regulatory status and evidence base differ.
References
- [Thymalin in the combined treatment of parkinsonism patients] — Lik Sprava, 1999External reference
- Class-level evidence — Histiocytosis-X — N Engl J Med, 1981External reference
- Class-level evidence — Peptides and Ageing — Neuro Endocrinol Lett, 2002External reference
- Class-level evidence — Analogues in immunology — Ric Clin Lab, 1984External reference
- Class-level evidence — Precursors of thymic peptides as stress sensors — Expert Opin Biol Ther, 2020External reference
Related research, comparisons & guides
Related peptides
Compiled by Peptide Library Editorial · Reviewed Aug 30, 2026 · Updated Aug 30, 2026 · Version 1
This Thymolin profile is compiled from published literature (5 cited studies linked above), public regulatory records and chemical registries. It describes what research reports; it is not medical advice, and nothing here is a dosing recommendation for humans. Peptide Library does not sell peptides. Editorial policy · How profiles are compiled · Report an error
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