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Immune

Thymosin Alpha-1

Also known as Ta1, Zadaxin

The gold-standard immune-modulating peptide.

Clinical evidence

Overview

Thymosin Alpha-1 (Ta1) is a 28-amino-acid peptide that occurs naturally in the thymus gland. It is sold under the brand name Zadaxin and is approved in more than 35 countries as a prescription drug for hepatitis B, hepatitis C, and immune support in cancer patients. In the United States it is compounded. How it works: Thymosin Alpha-1 trains and balances the immune system. Specifically, it enhances T-cell function and immune resilience - the branches of immunity responsible for recognizing and clearing pathogens and abnormal cells. It does not simply suppress or stimulate; it modulates, helping an underactive immune system become more competent and helping an overactive one settle into a healthier balance. Who tends to use it: People whose primary goal is immune support, as well as those focused on longevity at a secondary level. It is commonly used in chronic infection, post-illness recovery, and immunosenescence (age-related immune decline) protocols. How it is taken: Thymosin Alpha-1 is given by subcutaneous (SC) injection. The general dose range is 1.5-3 mg, administered 2-3 times per week. Timing is flexible - it can be injected at any time of day. Cycle length spans 4-12 weeks depending on goals and clinical response. What to expect: The effects of immune modulation are not dramatic in the way that a stimulant is - they build over weeks. Many people notice reduced frequency of illness or improved recovery speed over a cycle. Safety: Thymosin Alpha-1 is one of the most extensively studied and well-tolerated peptides in this category. The record notes it is used in chronic infection and recovery protocols. There are no excludeIf flags. It pairs well with Thymalin and LL-37 in immune stacks. Your licensed provider in the PepDepo network will set your dose and cycle at consult based on your immune history and goals.

At a glance

Route
SC injection
Dose
1.5-3 mg
Frequency
2-3x per week
Timing
Any time
Cycle
4-12 weeks

Combining

Stacks well with: Thymalin, LL-37

Safety

Well tolerated; used in chronic infection and recovery protocols.

Regulatory: Approved abroad (Zadaxin); compounded in the US.

Questions

How is Thymosin Alpha-1 given?⌄

By subcutaneous (SC) injection. The general range is 1.5-3 mg, given 2-3 times per week. Your exact dose is set at consult.

Does it matter what time of day I inject?⌄

No. The record lists timing as 'any time' - there is no requirement to inject at a specific point in the day.

How long is a typical course?⌄

4-12 weeks, depending on your goals and clinical response. Your clinician will guide the duration.

Who is it for?⌄

People focused on immune support as a primary goal, and longevity as a secondary. It is commonly used in chronic infection, post-illness recovery, and age-related immune decline protocols.

Is it approved anywhere?⌄

Yes. Thymosin Alpha-1 is sold as Zadaxin and is approved in over 35 countries for hepatitis and immune support. In the US it is compounded by licensed pharmacies.

Are there any contraindications?⌄

No excludeIf flags are listed - no contraindications for pregnancy or cancer history appear in the record. It is described as well tolerated.

Does it stack with other immune peptides?⌄

Yes. Thymalin and LL-37 are listed as synergy candidates. A clinician may suggest combining them depending on your immune goals.

Related protocols

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Exact dosing is set with a licensed provider in the PepDepo network. This page is education, not a prescription.

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Education only, not medical advice. Peptides discussed are for informational purposes and many are not FDA-approved. Eligibility, prescribing, compounding, and dispensing are handled by appropriately licensed entities. Exact protocols and dosing are set with a licensed provider in the PepDepo network at consult. Content is pending clinical review.