Comparison
Ashwagandha vs Thymosin Alpha-1
Side-by-side of Ashwagandha and Thymosin Alpha-1. Every row below is pulled from the compound schema and will update as our data grows. For deeper reads, follow through to each compound page.
Ashwagandha
Ashwagandha supplement guide: KSM-66 and Sensoril extracts at 300-600 mg/day cut morning cortisol and stress in RCTs. Dose, side effects, testosterone data.
Thymosin Alpha-1
Thymosin alpha-1 peptide (Zadaxin, thymalfasin): 28-amino-acid TA1 immunomodulator. Dosing, T-cell effects, hepatitis B and HCV adjunct evidence.
Effects at a glance
Ashwagandha
- •Reduces morning serum cortisol by ~20 to 30% at 300 to 600 mg/day standardized extract over 8 weeks
- •Lowers subjective stress on DASS-21 and PSS scales versus placebo in chronically stressed adults
- •Modest grip-strength and 1-RM gains of ~5 to 8% in trained men when paired with resistance training
- •Improves self-reported sleep quality and onset latency in adults with insomnia symptoms
- •Small testosterone increases (~10 to 15%) reported in stressed or subfertile men, less clear in healthy populations
- •May raise free T3 and T4; can interact with levothyroxine and unmask subclinical hyperthyroidism
Thymosin Alpha-1
- •28-amino-acid synthetic peptide identical to thymic-derived immunomodulator
- •Approved in over 35 countries as Zadaxin for hepatitis B, hepatitis C adjunct, and immune support
- •Not FDA approved in US; compounded by 503A/503B pharmacies for off-label immune support
- •Modulates T-cell maturation, NK activity, and Th1 polarization in immunocompromised states
- •Standard label dose: 1.6 mg subcutaneously twice weekly
- •Cleanest safety profile in the peptide class with hundreds of regulated trials behind it
Side-by-side
| Attribute | Ashwagandha | Thymosin Alpha-1 |
|---|---|---|
| Category | natural | peptide |
| Also known as | Withania somnifera, KSM-66, Sensoril | Talpha1, Ta1, Zadaxin, Thymalfasin |
| Half-life (hr) ↗ | 10 | 2 |
| Typical dose (mg) ↗ | 600 | 1.6 |
| Dosing frequency | daily | 2x weekly |
| Routes | oral | subcutaneous, intramuscular |
| Onset (hr) | 2 | 24 |
| Peak (hr) | - | 168 |
| Molecular weight | - | 3108.32 |
| Molecular formula | - | C129H215N33O55 |
| Mechanism | GABAergic modulation and HPA-axis attenuation; withanolides reduce cortisol secretion and inhibit NF-kB signaling. | Synthetic peptide modulator of innate and adaptive immunity. Promotes T-cell maturation and CD4/CD8 production, modulates Th1/Th2 balance, stimulates NK cell activity, and modulates TLR2/TLR9 signaling in dendritic cells. |
| Legal status | Dietary supplement in most jurisdictions; regulated in Denmark | Approved in 35+ countries as Zadaxin (hepatitis B, hepatitis C adjunct, immune support); not FDA approved in US; compounded by 503A/503B pharmacies for off-label use; not on WADA Prohibited List |
| WADA status | allowed | unknown |
| DEA / Rx | OTC supplement | Rx only via international approval or US compounding (no controlled-substance schedule) |
| Pregnancy | Not recommended | Not recommended; insufficient data |
| CAS | - | 62304-98-7 |
| PubChem CID | - | 16130571 |
| Wikidata | Q310109 | Q913854 |
Safety profile
Ashwagandha
Common side effects
- mild GI upset
- drowsiness
- headache
Contraindications
- pregnancy
- autoimmune disease (theoretical immune stimulation)
- hyperthyroidism
- concurrent sedative use
Interactions
- benzodiazepines: additive CNS depression(moderate)
- thyroid hormone (levothyroxine): may raise T3/T4, altering dose requirements(moderate)
- immunosuppressants: theoretical antagonism via immune stimulation(moderate)
Thymosin Alpha-1
Common side effects
- mild injection-site irritation (rare)
- transient mild fatigue (rare)
- occasional headache (rare)
Contraindications
- pregnancy
- lactation
- active organ transplant rejection therapy
- systemic immunosuppression for autoimmune disease (relative)
- severe active autoimmune disease (caution)
Interactions
- interferon-alpha: additive immune effect; used clinically in approved combination protocols(minor)
- calcineurin inhibitors (cyclosporine, tacrolimus): theoretical destabilization of immunosuppression; avoid(major)
- antimetabolites (azathioprine, mycophenolate): theoretical destabilization of immunosuppression; avoid(major)
- vaccine administration: may augment vaccine response in elderly or immunocompromised; coordinate with clinician(minor)
Which Should You Take?
Ashwagandha comes out ahead for most readers on the criteria we weight: 3 catalogued goals, OTC dietary supplement, oral dosing, with a Tier-B outcome catalogued. Thymosin Alpha-1 is the right call when one of the conditionals below applies.
- → If your priority is stress and HPA-axis regulation, pick Ashwagandha.
- → If your priority is focus or working memory, pick Ashwagandha.
- → If your priority is immune support, pick Thymosin Alpha-1.
- → If your priority is post-training recovery, pick Thymosin Alpha-1.
Edge case: If you want to avoid Approved in 35+ countries as Zadaxin (hepatitis B, hepatitis C adjunct, immune support); not FDA approved in US; compounded by 503A/503B pharmacies for off-label use; not on WADA Prohibited List, Ashwagandha is the more accessible choice.
Default choice: Ashwagandha. Lower friction to source, and broader goal coverage. Reach for Thymosin Alpha-1 only if your priority sits squarely in the goals it owns above.
This verdict is generated from each compound's schema (goals, legal status, evidence outcomes, dosing route). It updates automatically as our compound data evolves; the deeper read sits on each individual compound page.
Common questions
What is the difference between Ashwagandha and Thymosin Alpha-1?
Ashwagandha and Thymosin Alpha-1 differ in category (natural vs peptide), mechanism, and typical dosing. See the side-by-side table for full details.
Which has a longer half-life, Ashwagandha or Thymosin Alpha-1?
Ashwagandha half-life is 10 hours; Thymosin Alpha-1 half-life is 2 hours.
Can you stack Ashwagandha with Thymosin Alpha-1?
Stack compatibility depends on mechanism overlap, legal status, and individual response. Check each compound page for specific interactions and contraindications before combining.
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