Thymalin

Quickstart Highlights

Thymalin is a polypeptide complex extracted from calf thymus, developed by the Khavinson group and registered in Russia as an intramuscular immunomodulator. It is studied for restoring T-cell maturation, normalizing the CD4/CD8 ratio and, in long-term elderly cohorts, for geroprotective effects. This educational protocol presents a short course of 5–10 mg once daily for 5–10 consecutive days, using 1.0 mL bacteriostatic water per 10 mg vial (10 mg/mL) so that one vial is one day’s dose (at 5 mg the remaining half is discarded, because the solution is used the same day). The subcutaneous route shown here is a research-community convention; all human data use intramuscular injection.

• Reconstitute: Add 1 mL bacteriostatic water → 10 mg/mL concentration.
• Dose range: 5–10 mg once daily for 5–10 consecutive days, subcutaneously or intramuscularly (course repeated 1–2 times per year).
• Easy measuring: At 10 mg/mL, 1 unit = 0.01 mL = 100 mcg on a U-100 insulin syringe.
• Storage: Lyophilized: freeze at −20 °C (−4 °F); after reconstitution, refrigerate at 2–8 °C (35.6–46.4 °F) and use within 1 day.
• Label: The Russian label directs dissolving the vial immediately before injection and using it the same day; one 10 mg vial covers one day at either 5 mg or 10 mg, so a 10-day course uses 10 vials.

Protocol Overview

Concise summary of the short-course regimen.

• Goal: Support thymus-dependent immunity by restoring T-cell maturation and the CD4/CD8 balance, with geroprotective effects reported in long-term elderly cohorts.
• Schedule: Once-daily injections (subcutaneous by convention; intramuscular per the label) for 5–10 consecutive days, with the course repeated 1–2 times per year or every 1–6 months as indicated.
• Dose Range: 5 mg (5000 mcg) to 10 mg (10000 mcg) once daily; the Russian label spans 5–20 mg daily for 3–10 days (30–100 mg per course).
• Reconstitution: 1 mL per 10 mg vial (10 mg/mL) for accurate unit measurements on standard insulin syringes.
• Storage: Lyophilized frozen at −20 °C (−4 °F); reconstituted refrigerated at 2–8 °C (35.6–46.4 °F); use within 1 day; avoid repeated freeze–thaw cycles.
• Evidence: Registered Russian prescription drug with decades of Russian-language clinical use and one research group’s cohort data, but no independent Western RCT; the subcutaneous route is a community convention with no human data. Confidence is medium for the label course and low for the route.

Dosing Protocol

Suggested short-course approach based on the Russian prescribing label and research-community conventions.

• Prophylactic course dose: 5 mg (5000 mcg) once daily (50 units at 10 mg/mL), matching the label’s prophylactic range of 5–10 mg daily for 3–5 days.
• Standard course dose: 10 mg (10000 mcg) once daily, the full 1.0 mL draw (100 units) and the modal community figure; the label’s treatment range runs 5–20 mg daily.
• Frequency: Once per day; no titration or loading phase appears in any source.
• Timing: Morning preferred. Thymalin is not activating and has no fasting requirement; one source allows early evening.
• Cycle: 5–10 consecutive days per course (label: 3–10 days, 30–100 mg per course); the longevity convention is 10 mg daily for 10 days.
• Repeat courses: Repeat 1–2 times per year, or every 1–6 months as indicated on the label; no maintenance phase is described in any source.
• Split injection: At 10 mg the full 1 mL draw may be split as 50 units into each of two sites, which also keeps each injection within the 80-unit V1 pen setting limit.

Storage Instructions

Proper storage preserves product quality and efficacy.

• Lyophilized (powder): Store at −20 °C (−4 °F) or refrigerate at 2–8 °C (35.6–46.4 °F), dry and protected from light; the label allows dry, dark storage up to 20–25 °C (68–77 °F) with a 2–3 year shelf life.
• Reconstituted (solution): Refrigerate at 2–8 °C (35.6–46.4 °F) and use within 1 day. The label directs dissolving the vial immediately before injection, and the reference calculators say not to store reconstituted thymalin at all; the 28–30 day figures some vendors quote assume bacteriostatic water and have no label basis.
• Allow vials to reach room temperature before opening to minimize condensation uptake.
• Do not freeze the reconstituted solution; dissolve one vial per day rather than preparing several days in advance.

Important Notes

Practical considerations for consistency and safety.

• Use new sterile insulin syringes for each injection; dispose in a proper sharps container.
• Rotate injection sites systematically (abdomen, thighs, upper arms for subcutaneous use; deltoid, vastus lateralis or dorsogluteal muscle for intramuscular use) to reduce local irritation.
• Inject slowly and steadily; wait a few seconds before withdrawing the needle to ensure complete delivery.
• Route: All human data and the Russian label use intramuscular injection. The subcutaneous figures in community sources copy the intramuscular mg dose with no adjustment for route, and no controlled trial supports subcutaneous use.
• Dose scale: Thymalin is dosed in mg, not mcg. A 10 mg vial is a single day’s dose at the standard figure, so a 10-day course at 10 mg daily uses 10 vials; because the solution is used the same day, a 5 mg dose leaves half a vial unused.
• Identity: Thymalin is a natural bovine thymic extract, not a single synthetic peptide. It is distinct from Thymogen (the Glu-Trp dipeptide) and from Thymosin Alpha-1, which has its own labeled dosing of 1.6 mg subcutaneously twice weekly.
• Regulatory status: Not approved by Health Canada or the FDA; registered as a prescription drug in Russia and sold as research material in North America.
• Evidence caveat: The human data come from one Russian research network over 40 years with no Western replication; long-term immunomodulatory safety is not characterized, and as a bovine extract the product carries hypersensitivity and gray-market sterility or endotoxin risk. The label contraindicates use in pregnancy and lactation.

How This Works

Thymalin is a polypeptide complex extracted from calf thymus, the Khavinson bioregulator from which the synthetic dipeptide Thymogen (Glu-Trp) was later derived. It acts on thymus-dependent immunity: the extract drives hematopoietic precursors toward mature T-cell differentiation and restores the balance between helper and cytotoxic T cells, which is reflected clinically as a normalized CD4/CD8 ratio. Downstream, IL-2 and interferon-gamma output normalize, and in vitro the dipeptide components lowered IL-1, IL-6 and TNF-alpha. The Khavinson group also attributes geroprotective effects to peptide-mediated changes in gene expression and cytokine signaling, and reports an approximately 2-fold reduction in all-cause mortality over 6–15 years in a 266-subject elderly cohort. All of this evidence comes from one Russian research network using intramuscular courses of 5–20 mg daily for 3–10 days; there is no independent Western randomised trial and no human data for the subcutaneous route.

Potential Benefits & Side Effects

Observations from Russian clinical literature and single-group cohort data.

Potential Benefits:

• Restored T-cell maturation and function, with normalization of the CD4/CD8 ratio and lymphocyte profiles in immunodeficient states (Russian clinical studies).
• Fewer infectious complications after short courses; label indications include immune deficiency, chronic infection and recovery after chemotherapy, radiation or surgery (Russian clinical use).
• Reduced all-cause mortality in elderly cohorts, approximately 2-fold over 6–15 years, in the Khavinson group’s single-source data (n=266).
• Lowered pro-inflammatory cytokines (IL-1, IL-6, TNF-alpha) in vitro, with geroprotective gene-expression effects described by the same group.
• Respiratory and COVID-19 adjunct benefit reported in small Russian studies.

Potential Side Effects:

• Allergic or hypersensitivity reactions, the only side effect listed on the Russian label; the product is a bovine-thymus-derived extract.
• Injection-site discomfort, redness, and brief warmth or flushing.
• Transient fatigue in the first days; rare nausea or headache.
• Contraindicated in pregnancy and lactation; the label advises caution with an allergic history and certain endocrine conditions.
• Long-term immunomodulatory safety has not been characterized, and gray-market product carries sterility and endotoxin risk.

Lifestyle Factors

Complementary strategies for immune resilience during and between courses.

• Prioritize 7–9 hours of consistent sleep, which supports normal T-cell function and immune recovery.
• Maintain adequate protein intake and a diet supplying zinc, vitamin D and other micronutrients involved in lymphocyte development.
• Keep regular moderate exercise; avoid prolonged exhaustive training during the course, which transiently suppresses immune function.
• Manage chronic stress, since sustained cortisol elevation counteracts thymus-dependent immunity.
• Limit alcohol and tobacco, both of which impair immune cell function.
• Record each course date, dose and route so that repeat courses follow the 1–6 month label interval.

Injection Technique

General subcutaneous injection guidance from clinical best-practice resources.

• Clean the vial stopper and chosen skin site with separate alcohol swabs; allow both to dry completely before proceeding.
• For subcutaneous use, pinch a fold of skin between your fingers and insert the needle at a 45–90° angle into the subcutaneous tissue (fatty layer, not muscle).
• For the labeled intramuscular route, use a longer 25–27 g needle inserted at 90° into the deltoid, vastus lateralis (outer thigh) or dorsogluteal muscle; a 29–31 g insulin needle is suited to subcutaneous use only.
• At the 10 mg dose the full 1 mL draw (100 units) may be split as 50 units into each of two sites, which reduces local discomfort and keeps each injection within the 80-unit V1 pen limit.
• Do not aspirate when giving a subcutaneous injection; inject the solution slowly and steadily and wait at least 6 seconds before withdrawing the needle to ensure complete delivery.
• Withdraw the needle and apply light pressure with a clean swab; rotate sites systematically (abdomen, thighs, upper arms, or alternating muscles for intramuscular use) across the 5–10 day course.
• Dispose of used syringes and needles immediately in a proper sharps container.

Recommended Source

We recommend Amino Labs for high-purity Thymalin (10 mg vials).

Note: Product availability and specifications subject to change. Verify current product details on supplier website.

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