Thymalin (Glu-Trp) Dosage Guide

Evidence-based protocols for the Khavinson thymic dipeptide bioregulator — intramuscular and subcutaneous dosing for immune restoration, reversing immunosenescence, anti-aging longevity, and stacking strategies.

Compiled by PeptideWiki Editorial Team·Last reviewed February 24, 2026

What Is Thymalin?

Thymalin is a synthetic dipeptide (L-glutamyl-L-tryptophan, or Glu-Trp) developed by Professor Vladimir Khavinson at the St. Petersburg Institute of Bioregulation and Gerontology in Russia. It belongs to the Khavinson family of peptide bioregulators — a class of short peptides designed to restore function to specific organs by modulating gene expression. Thymalin is the thymus-targeted bioregulator, alongside Epitalon (pineal gland), Cortagen (adrenal cortex), and Pinealon (central nervous system).

Thymalin was originally derived from thymus gland extracts and represents the minimal active sequence of thymic peptides — the smallest fragment that retains the ability to modulate thymic function. The thymus gland is a critical organ of the immune system responsible for T-cell maturation and differentiation. However, the thymus naturally involutes (shrinks and is replaced by fatty tissue) starting around puberty. By age 60–70, thymic output of new T-cells is dramatically reduced, contributing to immunosenescence — the age-related decline in immune function that increases susceptibility to infections, cancer, and autoimmune disorders.

Thymalin's research focus is on reversing this age-related thymic decline. Khavinson's clinical studies, conducted over decades primarily in elderly populations, reported that short courses of Thymalin improved T-cell counts, CD4/CD8 ratios, natural killer cell activity, and overall immune competence. Longer-term follow-ups (6–8 years) in some studies reported reduced infection rates and improved survival in elderly cohorts receiving periodic Thymalin courses.

Use our Peptide Dosage to calculate your exact dose based on vial size and concentration.

Dosing information in this guide is derived from Khavinson clinical protocols, community experience, and community protocols — not from approved pharmaceutical labeling.

Key Characteristics:

Synthetic dipeptide bioregulator (Glu-Trp) — L-glutamyl-L-tryptophan; the minimal active sequence derived from thymus gland extracts; only 2 amino acids
Thymic function restoration — modulates gene expression in thymic tissue to restore T-cell differentiation, maturation, and output — targeting the root cause of immunosenescence
Khavinson bioregulator family — part of the peptide bioregulator system alongside Epitalon (pineal), Cortagen (adrenal), and Pinealon (CNS) — each targeting a specific organ
Short-course protocol — administered as 5–10 day courses repeated every 6 months; designed to reset thymic function rather than provide continuous stimulation
Immune restoration in elderly populations — Khavinson’s clinical studies reported improved T-cell counts, CD4/CD8 ratios, NK cell activity, reduced infection rates, and improved longevity in elderly subjects
Very well-tolerated safety profile — no significant adverse effects reported in clinical studies, including in elderly and frail populations; potential concern in autoimmune patients

For a complete overview of thymic peptides and immune modulation, see our Thymosin Alpha-1 profile. New to peptides? Start with the Beginner's Guide to Peptides.

How Thymalin Dosage Is Determined

Thymalin dosing is derived directly from the Khavinson clinical protocols developed at the St. Petersburg Institute of Bioregulation and Gerontology. Unlike many research peptides where community experience drives dosing evolution, Thymalin's protocol has remained remarkably consistent since its clinical introduction — reflecting the bioregulator philosophy that a specific short-course dosage triggers lasting epigenetic changes in the target organ.

Khavinson Clinical Studies

Professor Vladimir Khavinson conducted multiple clinical studies spanning decades, primarily in elderly populations (60–80+ years old) in Russia. These studies used a standardized protocol of 10 mg Thymalin administered intramuscularly once daily for 5–10 consecutive days, with courses repeated every 6–12 months. Subjects were monitored with immune panel bloodwork including T-cell subsets (CD3, CD4, CD8), CD4/CD8 ratios, natural killer cell counts, and immunoglobulin levels. Results consistently showed improvements in these markers following Thymalin courses, with effects persisting for months between courses.

Bioregulator Peptide Theory

The dosing logic for Thymalin (and all Khavinson bioregulators) is rooted in the theory that short peptide sequences can interact with specific DNA regions and modulate gene expression in the target tissue. According to this model, a brief exposure (5–10 days) is sufficient to initiate a cascade of gene-expression changes that persist well beyond the administration period. This explains why Thymalin is not used continuously like most Western research peptides — the short course is the therapeutically active unit, not the individual daily dose.

Long-Term Longevity Follow-Up

Khavinson's most cited long-term studies followed elderly cohorts for 6–8 years, comparing those receiving periodic Thymalin (and/or Epitalon) courses against controls. The treatment groups showed reduced mortality rates, lower infection frequency, improved cardiovascular markers, and better overall functional status. While these results are striking, they come from studies published primarily in Russian journals and have not been independently replicated in large Western randomized controlled trials.

Community Protocol Refinements

Community practitioners have largely adopted the Khavinson protocol without major modifications. The primary community refinement has been the use of subcutaneous injection instead of intramuscular, at the same 5–10 mg dose, for ease of self-administration. Some practitioners use the lower end (5 mg) for maintenance courses and the higher end (10 mg) for initial or more aggressive immune restoration. A small number of practitioners have experimented with sublingual administration, but this remains highly experimental with limited data.

Strength of evidence: Moderate clinical (Russian literature), limited Western validation. Thymalin has more human clinical data than many research peptides, but this evidence comes primarily from Russian medical institutions and has not undergone the rigorous double-blind, placebo-controlled trials standard in Western regulatory frameworks. The Khavinson studies are peer-reviewed and span decades, but independent replication is needed. Treat the evidence as promising but not definitive.

Standard Thymalin Dosage Ranges

Thymalin dosing follows the Khavinson bioregulator model: short intensive courses rather than continuous daily use. The protocol is straightforward — a fixed daily dose for a defined number of days, repeated at regular intervals. This is fundamentally different from the titration-based, continuous dosing used for most Western research peptides.

Intramuscular Injection (Traditional Khavinson Protocol)

Protocol	Dose per Injection	Frequency	Course Length	Notes
Standard	10 mg	1x daily	5–10 days	Khavinson clinical protocol; repeat every 6 months
Conservative	5 mg	1x daily	10 days	Lower dose with extended course; used by some for maintenance
Aggressive	10 mg	1x daily	10 days	Full dose, full course length; for significant immune compromise

Subcutaneous Injection (Community Protocol)

Protocol	Dose per Injection	Frequency	Course Length	Notes
Standard	10 mg	1x daily	5–10 days	Same dose as IM; SubQ for easier self-administration
Conservative	5 mg	1x daily	10 days	Lower starting dose; commonly used by first-time users

Sublingual (Experimental)

Dose: 5–10 mg dissolved under the tongue, held for 60–90 seconds before swallowing
Frequency: 1x daily for 10–20 days
Status: Highly experimental with very limited data; some practitioners report using this route, but bioavailability is uncertain
Note: As a dipeptide, Thymalin's small size may allow some sublingual mucosal absorption, but this has not been validated in clinical studies

Course-based dosing is key: The most important aspect of Thymalin dosing is the course structure, not the individual daily dose. A 5–10 day course repeated every 6 months is the protocol — do not use Thymalin continuously. The short course triggers lasting changes in thymic gene expression that persist well beyond the administration period.

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Administration Routes Compared

Thymalin was originally developed for intramuscular injection, which was the standard route in Khavinson's clinical research. However, community use has expanded to include subcutaneous injection and experimental sublingual administration. Each route has trade-offs in terms of absorption, convenience, and evidence base.

Parameter	Intramuscular (IM)	Subcutaneous (SubQ)	Sublingual (Experimental)
Typical Dose	5–10 mg	5–10 mg	5–10 mg
Bioavailability	Highest (clinical standard)	High (comparable to IM)	Unknown (unvalidated)
Clinical Evidence	Strongest (Khavinson studies)	Community experience	Anecdotal only
Absorption Speed	Moderate (depot in muscle)	Slightly slower	Unknown
Ease of Use	Requires IM technique	Easiest injection	No injection needed
Pain / Discomfort	Moderate (deeper needle)	Minimal (shallow injection)	None
Community Popularity	Traditional users	Most popular	Niche / experimental

IM vs. SubQ for Thymalin: While the Khavinson clinical data used IM injection, subcutaneous injection at the same dose is widely used in the community with reported comparable results. Thymalin is a small dipeptide (only 2 amino acids) that is readily absorbed from subcutaneous tissue. The difference in absorption kinetics between IM and SubQ is unlikely to be clinically significant for a bioregulator protocol where the goal is cumulative exposure over a multi-day course rather than peak plasma concentration from a single dose.

Calculate Your Thymalin Dose

Thymalin is supplied as a lyophilized (freeze-dried) powder, typically in 10 mg vials. You reconstitute it with bacteriostatic water, then draw your dose using an insulin syringe. The reconstitution math is straightforward given the simple dosing protocol.

Worked Example:

Vial size: 10 mg of Thymalin
Bacteriostatic water added: 1 mL
Concentration: 10 mg ÷ 1 mL = 10 mg per mL
Target dose: 10 mg (full vial = one dose)
Volume to draw: 10 ÷ 10 = 1 mL = 100 units on an insulin syringe

Quick Reference — 10 mg Vial

Bac Water Added	Concentration	5 mg Dose	10 mg Dose
0.5 mL	20 mg/mL	25 units (0.25 mL)	50 units (0.5 mL)
1 mL	10 mg/mL	50 units (0.5 mL)	100 units (1 mL)
2 mL	5 mg/mL	100 units (1 mL)	Full vial

Practical tip: Since the standard Thymalin dose is 10 mg (the entire vial), many users reconstitute with 0.5–1 mL of bacteriostatic water to keep injection volumes small. If using 5 mg doses, reconstitute with 1 mL for easy measurement (0.5 mL = 5 mg). For a 10-day course at 10 mg/day, you will need 10 vials (one per day) unless using larger multi-dose vials.

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Thymalin Dosage by Goal

While Thymalin's dosing protocol is relatively uniform (short courses of 5–10 mg daily), the context and stacking approach varies by the primary goal. The same core protocol applies across use cases, but complementary peptides and monitoring strategies differ.

Immune Restoration in Aging (Anti-Immunosenescence)

The primary and most studied use case for Thymalin. Targets age-related thymic involution and the resulting decline in T-cell production, immune surveillance, and overall immune competence. This is the protocol with the strongest clinical evidence from Khavinson's long-term studies.

Dose: 10 mg daily (IM or SubQ)
Course: 10 days, repeated every 6 months
Monitoring: Immune panel bloodwork (CBC, T-cell subsets, NK cells) before and 4–8 weeks after each course
Stack: + Epitalon 10 mg daily for 10 days (pineal + thymic bioregulation for comprehensive anti-aging)

Post-Infection Immune Recovery

Following significant infections (viral, bacterial), the immune system can remain suppressed or dysregulated. A Thymalin course may help restore T-cell function and immune balance during the recovery phase, supporting the return to baseline immune competence.

Dose: 10 mg daily (IM or SubQ)
Course: 5–10 days, starting after the acute infection resolves
Timing: Begin after acute symptoms have resolved — not during active infection (NF-κB signaling is needed for pathogen clearance)
Stack: + Thymosin Alpha-1 1.6 mg 2–3x/week for direct T-cell stimulation alongside thymic restoration

Comprehensive Anti-Aging / Longevity Protocol

Combines Thymalin with other Khavinson bioregulators to address multiple organ systems involved in aging simultaneously. This is the most comprehensive application of the bioregulator philosophy — restoring function across the thymus, pineal gland, adrenal cortex, and nervous system in parallel.

Thymalin: 10 mg daily for 10 days (thymic / immune)
Epitalon: 10 mg daily for 10 days (pineal / melatonin / telomerase)
Cortagen: 10 mg daily for 10 days (adrenal / stress response)
Repeat: Entire protocol every 6 months
Note: Bioregulators can be administered concurrently (same course period) or sequentially (one after another)

Adjunct Immune Support (Cancer Surveillance)

Some practitioners use Thymalin as an adjunct to support immune surveillance capacity, particularly in individuals with a history of cancer or elevated cancer risk. The rationale is that restoring T-cell and NK cell function may improve the immune system's ability to detect and destroy abnormal cells. This application should only be pursued under direct medical supervision.

Dose: 10 mg daily (IM or SubQ)
Course: 10 days, repeated every 6 months
Medical supervision: Required — do not self-treat cancer or cancer risk with research peptides
Stack: + Thymosin Alpha-1 under physician guidance for enhanced immune surveillance

Cancer context requires medical supervision. While Thymalin may support immune surveillance, it is NOT a cancer treatment. Never use research peptides as a substitute for evidence-based oncology care. The immune-enhancing effects of Thymalin could also be contraindicated in certain cancers where immune activation is not desirable. Always work with an oncologist.

Cycling & Duration

Thymalin's cycling protocol is intrinsic to its design as a bioregulator peptide. Unlike continuous-use peptides (BPC-157, GHRPs) where cycling is a community-imposed best practice, the short-course structure IS the Thymalin protocol — it is how the peptide was used in clinical research from the beginning. The off-period is not a break; it is the period during which the bioregulatory changes initiated by the course take effect and persist.

Protocol	Course Length	Interval Between Courses	Notes
Standard Khavinson	10 days	6 months	The gold standard protocol from clinical studies; most commonly used
Abbreviated	5 days	6 months	Shorter course; may be sufficient for maintenance in younger individuals
Accelerated	10 days	3–4 months	More frequent courses; used by some for significant immune compromise
Long-Term Maintenance	5–10 days	6–12 months, ongoing	Indefinite periodic courses; the Khavinson longevity protocol approach

Why the off-period matters: In bioregulator peptide theory, the 5–10 day course initiates gene-expression changes in thymic tissue that unfold over the following weeks and months. The off-period is when T-cell differentiation improves, immune cell populations rebalance, and thymic functional restoration manifests in measurable bloodwork changes. Repeating courses too frequently provides no additional benefit and does not follow the clinical protocol.

When to Adjust Course Frequency

Shorten interval to 3–4 months if post-course bloodwork shows immune markers returning to baseline earlier than expected, or if the individual has significant immune compromise requiring more aggressive restoration.
Extend interval to 12 months if immune markers remain improved at the 6-month check, indicating the bioregulatory effect is persisting longer than typical. This is more common in younger individuals with less advanced thymic involution.
Standard 6-month interval is appropriate for most users and should be the default unless bloodwork indicates otherwise.
Indefinite continuation of periodic courses is the intended long-term approach. Khavinson's longevity studies followed patients through multiple course cycles over 6–8+ years.

Thymalin Stacking Protocols

Thymalin stacks naturally with other bioregulator peptides (targeting different organ systems) and with immune-modulating peptides that work through complementary mechanisms. The stacking approach reflects the bioregulator philosophy of addressing multiple aspects of aging or immune dysfunction simultaneously.

Thymalin + Epitalon — The Khavinson Longevity Stack (Most Popular)

The flagship Khavinson bioregulator combination and the most studied multi-peptide longevity protocol. Thymalin restores thymic function and immune competence, while Epitalon targets the pineal gland to restore melatonin production and activate telomerase. Together, they address two of the most significant pillars of age-related decline: immune deterioration and neuroendocrine dysfunction. This combination was used in Khavinson's longest-running longevity studies.

Compound	Dose	Route	Purpose
Thymalin	10 mg daily for 10 days	IM or SubQ	Thymic restoration; T-cell differentiation; immune competence
Epitalon	10 mg daily for 10 days	IM or SubQ	Pineal restoration; melatonin production; telomerase activation

Concurrent vs. sequential: Thymalin and Epitalon can be administered during the same 10-day course (injected at the same time or at different times of day) or run sequentially (Thymalin course first, then Epitalon course). Both approaches are used in the community. Concurrent administration is more practical (one course period instead of two), and there is no known interaction between the two peptides that would require separation.

Thymalin + Thymosin Alpha-1 (Upstream + Downstream Immune Modulation)

Combines Thymalin's thymic organ restoration (upstream — improving the factory that produces T-cells) with Thymosin Alpha-1's direct immune cell activation (downstream — stimulating existing immune cells to function more effectively). This is the most comprehensive thymic immune stack available.

Compound	Dose	Route	Purpose
Thymalin	10 mg daily for 10 days	IM or SubQ	Thymic organ restoration; T-cell production capacity
Thymosin Alpha-1	1.6 mg, 2–3x per week	SubQ	Direct T-cell activation; dendritic cell maturation; immune surveillance

Thymalin + Cortagen (Thymic + Adrenal Bioregulation)

Pairs the thymic bioregulator with the adrenal bioregulator for individuals dealing with both immune decline and chronic stress / adrenal dysfunction. Thymalin restores thymic function while Cortagen normalizes adrenal cortex function and cortisol regulation. Chronic stress is a known contributor to immune suppression, making this combination particularly relevant for stressed individuals with compromised immunity.

Compound	Dose	Route	Purpose
Thymalin	10 mg daily for 10 days	IM or SubQ	Thymic restoration; immune competence
Cortagen	10 mg daily for 10 days	IM or SubQ	Adrenal cortex regulation; cortisol normalization; stress adaptation

Thymalin + BPC-157 (Immune Restoration + Tissue Repair)

Combines immune restoration with systemic tissue repair support. Thymalin restores thymic function and T-cell output, while BPC-157 promotes angiogenesis, growth factor upregulation, and tissue healing. This stack is particularly relevant for individuals recovering from illness or surgery where both immune function and tissue repair are compromised.

Compound	Dose	Route	Purpose
Thymalin	10 mg daily for 10 days	IM or SubQ	Thymic restoration; immune system recovery
BPC-157	250–500 mcg, 1–2x daily	SubQ or Oral	Angiogenesis; growth factor upregulation; tissue repair

Stacking bioregulators is standard practice. Unlike some peptide stacks where interactions need careful consideration, Khavinson bioregulators are specifically designed to be combined because each targets a different organ system with no overlapping receptor mechanisms. The most common concern with Thymalin stacks is in autoimmune contexts — enhancing immune function while simultaneously using other immune-stimulating peptides requires caution if autoimmune conditions are present.

Explore more combinations with our Peptide Stack Builder or browse the Top 10 Peptide Stacks guide.

Safety, Side Effects & Contraindications

Safety Profile: Thymalin has demonstrated a very favorable safety profile across Khavinson's clinical studies, including in elderly and frail populations. No significant adverse effects were reported in published studies. The short-course protocol (5–10 days) inherently limits systemic exposure. Thymalin does not manipulate sex hormones, does not activate receptors prone to desensitization, and does not affect endocrine feedback loops. However, as an immune-enhancing peptide, caution is warranted in autoimmune conditions.

Reported Side Effects

Very rare and mild:

Injection site reactions (IM or SubQ) — minor redness, soreness, or swelling at the injection site; standard for any injectable peptide and typically resolves within hours
Mild fatigue or malaise during the first 1–2 days — reported occasionally, possibly related to immune system activation; self-resolving
Low-grade temperature elevation — rare; may indicate immune activation response; typically transient
Mild allergic reaction — extremely rare; discontinue immediately if rash, hives, or swelling occur

NOT associated with Thymalin:

No hormonal disruption (does not affect sex hormones, cortisol, or growth hormone axes)
No tanning, skin pigmentation, or sexual side effects
No appetite changes or metabolic effects
No water retention or bloating
No receptor desensitization or tolerance (bioregulatory mechanism)
No known drug interactions in published literature (though always inform your healthcare provider of all supplements and peptides)

Elderly population safety: Thymalin's safety in elderly populations is one of its distinguishing features. Khavinson's studies specifically enrolled subjects aged 60–80+ years, including those with multiple comorbidities. The short-course protocol and the peptide's targeted mechanism (thymic bioregulation without systemic immunosuppression or hormonal effects) make it one of the better-tolerated research peptides for older individuals.

Contraindications

Autoimmune diseases — Thymalin enhances immune function and T-cell activity. In autoimmune conditions (rheumatoid arthritis, lupus, multiple sclerosis, Hashimoto's thyroiditis, type 1 diabetes, etc.), the immune system attacks self-tissues. Enhancing immune function could theoretically worsen autoimmune activity. Use only under direct medical supervision if autoimmune conditions are present.
Organ transplant recipients on immunosuppressants — enhancing immune function could counteract immunosuppressive medications and increase rejection risk. Absolutely contraindicated without transplant physician approval.
Pregnancy and breastfeeding — no safety data exists for Thymalin during pregnancy or nursing. Avoid entirely.
Active severe infections — while Thymalin supports immune recovery, starting a course during an acute severe infection may not be appropriate. Wait until the acute phase resolves before beginning a course.
Known hypersensitivity — discontinue immediately if allergic reactions occur (rash, hives, difficulty breathing, swelling).

When to Stop or Seek Medical Attention

Any signs of allergic reaction (rash, hives, facial swelling, difficulty breathing) — seek immediate medical attention
Persistent fever above 38.5°C (101.3°F) during the course — this may indicate an underlying infection rather than a normal immune activation response
Worsening of any autoimmune symptoms if using Thymalin with a known autoimmune condition
Unusual fatigue, joint pain, or skin changes that develop during or shortly after a course
Any symptom that feels unusual or concerning — err on the side of caution with any research peptide

Regulatory Status: Thymalin is not FDA-approved for human use. It has been used clinically in Russia for decades under the name “Thymalin” as a pharmaceutical preparation, but this approval does not extend to Western regulatory jurisdictions. Outside of Russia, it is classified as a research peptide. Regulations vary by country — verify your local laws before purchasing.

Common Thymalin Dosing Mistakes

Avoid these common errors to get the most out of your Thymalin protocol:

Running continuous daily dosing for weeks or months: Thymalin is a bioregulator peptide designed for short courses (5–10 days), NOT continuous daily use. The Khavinson protocol relies on brief exposure to reset thymic gene expression, with effects persisting for months. Running Thymalin continuously like a daily peptide (e.g., BPC-157 or a GHRP) misunderstands its mechanism and provides no additional benefit beyond the standard course length.

Expecting immediate, dramatic results: Thymalin’s effects are subtle and develop over weeks to months as thymic function gradually restores. Unlike peptides that produce rapid, noticeable effects (tanning, appetite changes, acute healing), Thymalin works at the level of immune cell production and maturation. Results are best tracked with immune panel bloodwork, not subjective symptoms. Do not abandon the protocol because you don’t “feel” different after the 5–10 day course.

Confusing Thymalin with Thymosin Alpha-1: These are different peptides with different mechanisms. Thymalin (Glu-Trp) is a 2-amino-acid bioregulator that restores thymic organ function. Thymosin Alpha-1 is a 28-amino-acid peptide that directly stimulates immune cell populations. They have different dosing protocols, different mechanisms, and different use cases. They can be stacked, but they are not interchangeable.

Skipping the 6-month repeat course: The Khavinson protocol is designed as a recurring course — 5–10 days every 6 months. A single course may produce initial immune restoration, but the long-term benefits reported in Khavinson’s studies (reduced mortality, reduced infection rates over 6–8 years) required repeated courses. Doing one course and never repeating it undermines the protocol’s intended cumulative effect.

Using Thymalin with active autoimmune disease without medical supervision: Thymalin enhances immune function and T-cell activity. In autoimmune conditions (rheumatoid arthritis, lupus, multiple sclerosis, Hashimoto’s, etc.), the immune system is already overactive against self-tissues. Boosting immune function could theoretically worsen autoimmune flares. Always consult a healthcare provider before using any immune-stimulating peptide if you have an autoimmune condition.

Not getting baseline bloodwork: Without pre-course immune panel bloodwork (CBC with differential, T-cell subsets, NK cell counts), you have no objective way to measure whether Thymalin is producing the intended immune restoration. Subjective feelings are unreliable for tracking immune function. Get bloodwork before and 4–8 weeks after each course.

Storing reconstituted Thymalin improperly: Like all reconstituted peptides, Thymalin solution must be stored refrigerated at 2–8°C and used within 3–4 weeks. Given the short course length (5–10 days), a single reconstitution should last the entire course if stored properly. Do not freeze reconstituted peptide, and do not leave vials at room temperature. Use bacteriostatic water for reconstitution.

Assuming Western clinical trial validation exists: Thymalin’s clinical evidence comes primarily from Russian medical literature, particularly Khavinson’s studies at the St. Petersburg Institute of Bioregulation and Gerontology. While these studies are peer-reviewed and show compelling results, they have not been replicated in large, randomized, double-blind Western clinical trials. Approach the evidence with appropriate scientific rigor and recognize its current limitations.

Frequently Asked Questions

Key Takeaways

Thymalin (Glu-Trp) is a synthetic dipeptide bioregulator targeting the thymus — developed by Vladimir Khavinson to restore thymic function and reverse age-related immune decline (immunosenescence)
Short-course protocol, not continuous use: 10 mg daily (IM or SubQ) for 5–10 days, repeated every 6 months — this is the standard Khavinson clinical protocol
Part of the Khavinson bioregulator family — alongside Epitalon (pineal), Cortagen (adrenal), and Pinealon (CNS); each targets a different organ
Not the same as Thymosin Alpha-1 — Thymalin restores thymic organ function (upstream), while Thymosin Alpha-1 directly stimulates immune cells (downstream); they can be stacked for complementary effects
Gold standard stack: Thymalin + Epitalon for comprehensive anti-aging (thymic + pineal bioregulation) — the combination used in Khavinson's longevity studies
Get bloodwork: Immune panel (CBC, T-cell subsets, NK cells) before and 4–8 weeks after each course to objectively track immune restoration
Very well-tolerated — no significant adverse effects in clinical studies, including in elderly populations; rare injection site reactions only
Caution in autoimmune conditions — enhancing immune function could theoretically worsen autoimmune activity; use only under medical supervision if autoimmune disease is present
SubQ is the most popular community route — same dose as the original IM protocol, easier to self-administer, with comparable reported results
Evidence primarily from Russian clinical literature — peer-reviewed and spanning decades, but not independently replicated in large Western RCTs. Approach with appropriate scientific rigor.

This article is for educational and informational purposes only. See our Disclaimer.

References

Khavinson VKh, Morozov VG. “Peptides of pineal gland and thymus prolong human life.” Neuro Endocrinol Lett. 2003;24(3-4):233-240. PubMed
Khavinson VKh. “Peptide bioregulation of ageing.” Biogerontology. 2002;3(Suppl 1):36.
Anisimov VN, Khavinson VKh. “Peptide bioregulation of aging: results and prospects.” Biogerontology. 2010;11(2):139-149. PubMed
Khavinson VKh, Malinin VV. “Gerontological aspects of genome peptide regulation.” Karger. 2005.
Kuznik BI, et al. “Bioregulating peptides and the immune system: current state of the problem and prospective studies.” Adv Gerontol. 2017;30(6):836-847.
Khavinson VKh, et al. “Effects of Livagen peptide on chromatin activation in lymphocytes in elderly people.” Bull Exp Biol Med. 2002;134(4):389-392. PubMed
Anisimov VN, et al. “Effect of Epitalon on biomarkers of aging, life span and spontaneous tumor incidence in female Swiss-derived SHR mice.” Biogerontology. 2003;4(4):193-202. PubMed
Morozov VG, Khavinson VKh. “Natural and synthetic thymic peptides as therapeutics for immune dysfunction.” Int J Immunopharmacol. 1997;19(9-10):501-505. PubMed
Khavinson VKh, et al. “Mechanism of biological activity of short peptides: cell penetration and epigenetic regulation of gene expression.” Biology Bulletin Reviews. 2013;3(6):451-455.

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