Rankings / Sleep & Recovery

Thymosin alpha-1

Sleep & Recovery · Immunomodulatory peptide

Tier C+

peptideprescription
5.7 / 10
Tier C+
Ev 3 Bn 5 Sf 9

Bottom line

Read Off Label grades Thymosin alpha-1 as C+ (5.7/10) based on weak evidence, med benefit magnitude, and a low-risk safety profile.

Approved in >30 countries (not US).

Typical use: 1. — Rx in EU, Asia, Russia (Zadaxin); NOT FDA-approved in US; Category 2 on 503A bulks — compounding prohibited as of Jan 2025.

What this is

Approved in >30 countries (not US). Wu 2013 meta-analysis in sepsis showed mortality benefit. Used in long-COVID, Lyme, and chronic fatigue protocols with weak evidence. Same Jan 2025 FDA compounding restriction. Generally considered one of the better-studied 'biohacker peptides.'

Mechanism

28-amino-acid peptide derived from thymus prothymosin alpha; stimulates TLR9/Th1 immunity; activates dendritic cells and T-cell maturation; used in Europe/Asia for hepatitis B/C, sepsis, as vaccine adjuvant

Dose & route

1.6 mg subQ 2x/week (hepatitis indications); biohacker dosing similar

Common questions

Does Thymosin alpha-1 work?
Read Off Label rates the evidence for Thymosin alpha-1 as Weak and the benefit magnitude as med, producing an overall grade of C+ (5.7/10). Approved in >30 countries (not US).
Is Thymosin alpha-1 safe?
Thymosin alpha-1 has a low risk profile in published human data. Legal status: Rx in EU, Asia, Russia (Zadaxin); NOT FDA-approved in US; Category 2 on 503A bulks — compounding prohibited as of Jan 2025. This is not medical advice — see the disclaimer.
What is the typical dose for Thymosin alpha-1?
1.6 mg subQ 2x/week (hepatitis indications); biohacker dosing similar
How does Thymosin alpha-1 work?
28-amino-acid peptide derived from thymus prothymosin alpha; stimulates TLR9/Th1 immunity; activates dendritic cells and T-cell maturation; used in Europe/Asia for hepatitis B/C, sepsis, as vaccine adjuvant

This is an independent synthesis of published research by a non-clinician. Scores are opinions supported by citations, not prescriptions. See the full disclaimer and methodology for how this score was produced and what it does and doesn't mean.