What are the side effects of Thymosin Alpha-1 (Tα1)?
The most commonly reported Thymosin Alpha-1 (Tα1) side effects are generally well tolerated, mild injection-site irritation. Most are mild and tend to be dose dependent. It is generally avoided with active immunosuppression therapy (talk to provider). Human clinical evidence for Thymosin Alpha-1 (Tα1) is limited, so this reflects reported and observed effects, not a complete safety profile.
Reported Thymosin Alpha-1 (Tα1) side effects
- Generally well tolerated
- Mild injection-site irritation
Who should avoid it
- Active immunosuppression therapy (talk to provider)
- Pregnancy / nursing
Bloodwork worth tracking
- CBC if running long term
References
- Thymosin alpha 1 in chronic hepatitis B and C — Sherman KE et al., Gut, 2003
- The efficacy and safety of thymosin alpha1 for sepsis (TESTS): multicentre, double blinded, randomised, placebo controlled, phase 3 trial — Wu J et al., BMJ, 2025
- The efficacy of thymosin alpha 1 for severe sepsis (ETASS): a multicenter, single-blind, randomized and controlled trial — Wu J et al., Critical Care, 2013
Pepdex is an editorial reference, not medical advice. Peptides vary in legal and approval status by country, many are research compounds without full human safety data. Talk to a qualified clinician before starting anything.
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Last updated 2026-06-06.