Thymalin

What Thymalin does

Thymalin is a mixture of peptides extracted from calf thymus and prescribed in Russia. Small studies of immune problems, infections and ageing report benefits that other research teams need to confirm. Long-term safety and the contents of online products remain uncertain. It has no FDA approval.

• In a small trial of hospital COVID-19 patients, fewer deaths were reported with it; other teams need to confirm this. (Studied in a trial)
• In another trial of COVID-19 patients, immune and inflammation blood markers improved. (Studied in a trial)
• In small older studies, older adults given repeated courses had fewer deaths, though this does not prove longer life. (Studied in a trial)
• In uncontrolled accounts, one user reported better sleep and skin, and another a shorter chest cold. (Reported by users)

Uses in the sources

• Studied as an add-on for hospitalised COVID-19, immune deficiency, infections and recovery after injury. (Studied in a trial) (source)
• Older adults received intermittent courses in historical studies. These findings do not establish longer life in healthy adults. (Studied in a trial) (source)
• People report using it with Epitalon and GHK-Cu for skin or hair. No trial tested that three-peptide stack. (Reported by users) (source)

Thymalin dosage

Typical reported dose: 5–20 mg once a day, 30–100 mg per course

• COVID-19: 10 mg for 10 days: 10 mg once daily for 10 days once daily, into muscle. Studied in a trial. Studied in: Hospitalised adults with severe COVID-19. (source)
• COVID-19: 10 mg for five days: 10 mg once daily for 5 days once daily, into muscle. Studied in a trial. Studied in: Adults hospitalised with moderate or severe COVID-19. (source)
• Older adults: two annual courses: 10 mg daily for 10 days in 1996, repeated in 1997 once daily during each course, into muscle. Studied in a trial. Studied in: Women aged 66–94 in a veterans home. (source)
• Two annual courses of both extracts: 10 mg Thymalin plus 10 mg Epithalamin daily for 10 days once daily during each course, into muscle. Studied in a trial. Studied in: Women aged 66–94 in the randomized veterans-home study. (source)
• Older adults: five spaced doses: 10 mg per injection; 5 injections every 2–3 days one injection every 2–3 days, into muscle. Studied in a trial. Studied in: Older adults with accelerated ageing or coronary disease. (source)
• Annual Thymalin and Epithalamin: 10 mg Thymalin plus 10 mg Epithalamin daily for 10 days once daily during each course, into muscle. Studied in a trial. Studied in: Separate group of 20 older adults. (source)

These are doses reported in labels, trials or user reports, not a personal plan. Check the source behind each one.

Work out syringe units with the dosing calculator

How to mix Thymalin

Comes as: Freeze-dried calf-thymus extract in a 10 mg vial.

Mixed with: Russian instructions: dissolve one 10 mg vial in 1–2 mL isotonic sodium chloride solution..

Common vial sizes: 10 mg. Common water amounts: 1, 2 mL.

• The listed 1–2 mL volumes refer to saline, not bacteriostatic water.
• The original vial contains 20 mg glycine in addition to 10 mg extract.
• Vial capacity is 5 mL; that is not a required mixing volume.
• Forum bacteriostatic-water mixing appears separately as community evidence.
• These are Russian product instructions, not an FDA or EMA-approved handling label.

Before mixing: The retrieved manufacturer insert says protect from light at ≤20°C. Current Vidal information lists 2–25°C; follow the matching package.

After mixing: Prepare just before injection. No validated multi-day storage time for mixed Thymalin was located.

Thymalin side effects and risks

Reported side effects

• Allergic reactions: Russian instructions list allergy without a rate., serious. Stop the product; breathing trouble, swelling or fainting needs emergency care. (source)
• Headache reported online: One commenter asked about a migraine like headache; causation was not established., mild. A new severe or persistent headache needs assessment. (source)
• Irritability while stacked: One user reported mood swings while also taking Epitalon; later attribution was uncertain., moderate. Review all drugs and pause the suspected product if symptoms appear. (source)

Stop and get help if

• Trouble breathing, throat or face swelling, or collapse after injection: Stop and call emergency services now.
• Fever with shaking chills, confusion, or spreading redness after injection: Seek urgent care for possible serious infection or contaminated product.
• New chest pain, severe breathlessness, fainting or heavy bleeding: Seek emergency care now.

Who should avoid it

• pregnant: Russian instructions contraindicate use during pregnancy.
• breastfeeding: Russian instructions contraindicate use during breastfeeding.
• tryingToConceive: Precaution: reproductive safety is unestablished; pregnancy is contraindicated in the Russian instructions.
• under18: Historical pediatric reports do not establish safety for unsupervised use.
• other: Individual intolerance is a stated contraindication. The product is derived from cattle and contains glycine.
• autoimmuneDisease: It changes immune activity. Old autoimmune-disease reports do not establish safety across conditions.
• immunosuppressed: Immune effects may conflict with transplant or immune-suppressing care. Direct interaction studies are missing.
• activeCancer: Historical cancer adjunct reports do not establish safety with modern cancer therapy. Oncology review is needed.
• kidneyDisease: No validated dose adjustment; renal failure was excluded from the retrospective COVID-19 study.
• liverDisease: No validated dose adjustment; raised liver enzymes were excluded from that COVID-19 study.
• bleedingDisorder: Historical studies report changes in clotting and fibrinolysis; bleeding risk is not quantified.
• testedAthlete: Thymalin is not named on the 2026 list; the exact product needs an anti-doping ruling.

Interactions

• Immune-suppressing drugs: Possible opposing immune effects are theoretical. Historical co-use does not establish safety, especially after transplant.
• Anticoagulants and antiplatelet drugs: Clotting changes were observed; interaction and bleeding rates are unknown. Hospital heparin co-use is not proof of general safety.
• Other thymus immune peptides: Overlapping immune effects; no validated combined regimen. Similar names do not mean the same drug.

Product quality risks

• A vial containing a single synthetic peptide is not proven equivalent to the studied thymus extract.
• No independent peer-reviewed survey of online Thymalin identity, dose, sterility or endotoxin was located.
• Regulators report contamination, uncertain doses and serious reactions with unapproved peptides generally.
• General online semaglutide testing found quality failures; those results do not measure Thymalin failure rates.

What to expect

The 156 possible clinical reports include older records without summaries and reports that may reuse participants. They are not 156 independent trials; dose and safety details are often missing.

Key studies

• COVID-19: 10-day injections: A small trial reported fewer hospital deaths; replication is needed. (source)
• COVID-19: five-day injections: Immune and inflammation markers improved in an open-label trial. (source)
• COVID-19 antibodies at 104 days: Antibody levels fell less after Thymalin; protection from reinfection was not tested. (source)
• COVID-19 antibodies at 200 days: A follow-up report described higher antibody levels after Thymalin. (source)
• COVID-19 immune markers at six days: Retrospective analysis of immune-marker changes, not a new survival trial. (source)
• COVID-19: clotting and mortality: A comparative report found lower mortality with Thymalin; causal certainty is low. (source)

Thymalin FAQ

• Is Thymalin FDA-approved? No. FDA named a Thymalin product as unapproved in a 2024 warning letter. Russian registration is separate from US approval.
• How do people take it? Into muscle, once daily. 3–10 days; course total 30–100 mg. Source: clinician-published.
• What's the difference between Thymalin and Epitalon? Thymalin: a calf thymus extract studied for immune problems, with uncertain safety and product identity. Epitalon: a peptide with telomerase effects in cells, but no proof that people live longer. Why people pair them: people pair it with Thymalin for longevity or sleep; this specific pair lacks clinical trial evidence.
• Can I take it with Epitalon? People pair it with Thymalin for longevity or sleep; this specific pair lacks clinical trial evidence. Irritability was reported with the pair. Epithalamin extract trials do not validate synthetic Epitalon. Source: reported by users. Ask a doctor before combining anything.
• Is it banned in sport? It is unclear (WADA 2026). S0 applies when no government health authority approves human therapeutic use. Russian Thymalin registration prevents an automatic S0 conclusion.
• How long does a mixed vial last? Prepare just before injection. No validated multi-day storage time for mixed Thymalin was located.