pepdex
№ 066

Thymalin

A polypeptide complex extracted from calf thymus, distinct from Thymosin Alpha-1. Used in Russian and Eastern European clinical practice for immune restoration in elderly patients and post-illness recovery.

Immune
Evidence: Anecdotal
Half-life ⓘ
Short — minutes in plasma; biological effect persists days
Route ⓘ
Intramuscular (clinical) or subcutaneous (research use)
Cycle ⓘ
10-day course, repeated 2-3x per year
Schedule
Daily for 10 days, then off
Status & legalityWhat do these mean? →
Natty? ⓘ
Not natty

Polypeptide complex, not a defined-sequence single peptide. Distinct from Thymosin Alpha-1.

FDA ⓘ
Not approved

Not FDA approved. Used in Russia and parts of Eastern Europe under their domestic clinical-pharmacology framework.

Compounding ⓘ
Not classified

Not formally categorized in the FDA bulks lists.

WADA ⓘ
Not listed

Falls outside explicit S2 listing, but immune-modulator status is grey-zone for tested athletes.

Prescribed ⓘ

Prescribed in Russian clinical settings for geriatric immune restoration. Not available by US prescription.

Who it's for

  • →People researching immune-aging interventions
  • →Users running it alongside Thymosin Alpha-1 for redundant immune signaling
  • →Russian-bioregulator-protocol followers

What to expect

  1. Week 1

    Subjective energy / sleep improvements reported by some users.

  2. Week 4

    Course typically already finished. Effect window is the 10-day pulse plus residual.

  3. Week 8

    Out of cycle — wait for next quarterly course.

Dosing protocol

Members only

Stacks well with

Members only

Stack essentials

Most users on Thymalin run these alongside it. Each one fixes a specific deficiency, side effect, or synergy gap — not optional extras if you want full results.

Omega-3 (EPA/DHA)
Immune-modulator pairs naturally with the anti-inflammatory baseline omega-3 provides
See dose →
Don't have the injection kit yet?
Insulin syringes, alcohol pads, sharps disposal, and vial storage — quality-checked, top-rated picks.
Browse injection supplies →

Side effects

Members only

When NOT to use

Members only

Bloodwork to monitor

Members only

Common mistakes

Members only

The Pepdex take

Members only

Unlock the rest on Thymalin

Members get the full mechanism, dose protocols, side effects, contraindications, common mistakes, drug interactions, and the Pepdex hot take — on every entry.

  • ✓ Mechanism
  • ✓ Dose protocols
  • ✓ Side effects
  • ✓ Drug interactions
  • ✓ Common mistakes
  • ✓ The Pepdex take
  • ✓ Members-only Sources page — community-curated reference for research-grade material
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Frequently asked

Is Thymalin FDA approved?+
Not FDA approved. Used in Russia and parts of Eastern Europe under their domestic clinical-pharmacology framework.
Is Thymalin banned by WADA?+
Thymalin is not currently on the WADA prohibited list. Falls outside explicit S2 listing, but immune-modulator status is grey-zone for tested athletes.
Are you still natty after taking Thymalin?+
No. Polypeptide complex, not a defined-sequence single peptide. Distinct from Thymosin Alpha-1.
Do doctors prescribe Thymalin?+
Prescribed in Russian clinical settings for geriatric immune restoration. Not available by US prescription.
What's the typical dose of Thymalin?+
5-10 mg per dose, daily for 10 days. Russian clinical literature uses 10 mg IM; community sub-q protocols typically run 5-10 mg.
What are the side effects of Thymalin?+
Common side effects include: Mild injection-site irritation; Transient flu-like feeling in first 1-2 doses (rare); Most users report no notable side effects. Less common effects and full safety details are on the entry page.
How long until Thymalin starts working?+
Subjective energy / sleep improvements reported by some users.

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