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Immune support

Thymalin

Also known as: Thymus polypeptide fraction · Thymalinum

A polypeptide fraction extracted from thymus tissue, studied in Russian research for immune regulation.

Thymalin at a glance

NameThymalin
Also known asThymus polypeptide fraction, Thymalinum
CategoryImmune support
TypePeptide
SequenceThymus polypeptide fraction (mixture, not a single defined sequence)
Typical dose~10 mg per day
FrequencyOnce daily over short courses in reported use
RouteIntramuscular injection (research)
Half-lifeNot well characterized; considered short-acting.

Overview

Thymalin is a preparation of small polypeptides isolated from the thymus gland of cattle, developed within Soviet and Russian research on the thymus and immunity. It is commonly cited in that literature for context on restoring immune balance, particularly T-cell function. The evidence base is largely non-Western and older, and independent large-scale clinical trials are limited.

How it’s thought to work

  • Reported to influence differentiation and activity of T-lymphocytes.
  • Appears to help normalize immune cell ratios in some studies.
  • Studied for modulation of inflammatory and immune signaling.
  • Described as a thymic peptide bioregulator rather than a single receptor ligand.

Researched uses

  • Immune modulation in Russian clinical reports
  • Support during infection or immune suppression (research)
  • Age-related immune decline studies
  • Adjunct research in inflammatory conditions

Commonly cited protocol

Typical dose~10 mg per day
FrequencyOnce daily over short courses in reported use
RouteIntramuscular injection (research)
NotesTraditionally supplied as a lyophilized powder for reconstitution.

Reconstitution

Commonly a 10 mg vial; 10 mg in 2 mL gives 5 mg/mL, so a 10 mg dose is about 40 units on a U-100 syringe.

Thymalin dosage calculator

The calculator below is pre-filled with Thymalin’s commonly cited vial size and dose. Adjust the vial amount, bacteriostatic water, or dose to match your own vial — it will show the exact insulin-syringe units to draw, the concentration, and how many doses the vial holds.

mg
mL
How much water you add is your choice — it doesn’t change your dose, only how many units you draw. Common:
Draw to
200 units
= 2 mL on a 1 mL (100 units) syringe
100 units0100
Concentration
5 mg/mL
Per unit
50 mcg/u
Doses per vial
1 × 10000mcg
Volume
2 mL
📋 In plain English

Add 2 mL of bacteriostatic water to your 10 mg vial. That gives you about 1 doses of 10000 mcg. For each dose, draw 200 units into a 100-unit insulin syringe.

⚠️ The dose needs 200 units — more than a full 1 mL (100 units) syringe (100 u). Use a larger syringe, add less water, or split the injection.

See the full Thymalin dosing chart (units for every dose & water amount), or open the full peptide calculator →

Cautions

  • Not FDA-approved; regulatory status outside its origin countries is that of a research chemical.
  • Most evidence is non-Western, older, and of limited quality.
  • Composition is a fraction, so batch consistency can vary.
  • Human safety data are limited.

Thymalin FAQ

What is Thymalin?

A polypeptide fraction extracted from thymus tissue, studied in Russian research for immune regulation.

How does Thymalin work?

Reported to influence differentiation and activity of T-lymphocytes. Appears to help normalize immune cell ratios in some studies. Studied for modulation of inflammatory and immune signaling. Described as a thymic peptide bioregulator rather than a single receptor ligand.

What is Thymalin used for?

Immune modulation in Russian clinical reports; Support during infection or immune suppression (research); Age-related immune decline studies; Adjunct research in inflammatory conditions.

What is a typical Thymalin dose?

~10 mg per day, Once daily over short courses in reported use, Intramuscular injection (research). This is a commonly cited figure for context only, not medical advice.

How do you reconstitute Thymalin?

Commonly a 10 mg vial; 10 mg in 2 mL gives 5 mg/mL, so a 10 mg dose is about 40 units on a U-100 syringe.

What is the half-life of Thymalin?

Not well characterized; considered short-acting.

Related immune support peptides

⚠️ Educational reference only — not medical advice. These compounds are largely research chemicals not approved for human use in most countries. Nothing here is a recommendation to obtain or administer any substance. Consult a qualified clinician.