Comparison
Modafinil vs TB-500
Side-by-side of Modafinil and TB-500. 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.
Modafinil
Modafinil cognitive enhancement profile: wakefulness-promoting agent, 100-200 mg dosing, 12-15 hour half-life, off-label nootropic use, Schedule IV status.
TB-500
TB-500 peptide, a 17-aa thymosin beta-4 fragment. Preclinical tendon and wound healing via actin sequestration. Typical dosage 2 to 5 mg weekly. No human RCTs.
Effects at a glance
Modafinil
- •FDA approved in 1998 for narcolepsy, with later additions for shift-work sleep disorder and OSA residual sleepiness
- •Schedule IV controlled substance in the US; prescription-only in EU, UK, Australia
- •Increases wakefulness via weak dopamine reuptake inhibition plus histaminergic, noradrenergic, and orexinergic activation
- •Long half-life of 12 to 15 hours requires morning dosing to avoid sleep disruption
- •Modest cognitive enhancement signal in non-sleep-deprived adults at 100 to 200 mg (Battleday meta-review 2015)
- •Substantial CYP3A4 induction reduces hormonal contraceptive efficacy; barrier methods recommended
TB-500
- •17-amino-acid fragment of endogenous Thymosin Beta-4, an actin-sequestering peptide
- •Preclinical models show accelerated tendon, ligament, and dermal wound healing
- •Equine veterinary use for soft-tissue injury is the most documented real-world application
- •Anecdotal human protocols use 2 to 5 mg twice weekly subcutaneously for 4 to 6 weeks
- •WADA banned under S2 (peptide hormones, growth factors) since 2018
- •No completed phase II or III human RCTs as of 2026; long-term safety unestablished
Side-by-side
| Attribute | Modafinil | TB-500 |
|---|---|---|
| Category | pharmaceutical | peptide |
| Also known as | Provigil, Modalert, Modvigil, diphenylmethylsulfinyl-acetamide | Thymosin Beta-4 fragment, TB4-Frag, Thymosin Beta 4 |
| Half-life (hr) ↗ | 13 | 2 |
| Typical dose (mg) ↗ | 200 | 2.5 |
| Dosing frequency | daily, morning | 2x weekly (anecdotal protocols) |
| Routes | oral | subcutaneous, intramuscular |
| Onset (hr) | 1 | - |
| Peak (hr) | 3 | - |
| Molecular weight | 273.35 | 4963.4 |
| Molecular formula | C15H15NO2S | C212H350N56O78S |
| Mechanism | Weak dopamine reuptake inhibition plus downstream activation of histaminergic, noradrenergic, and orexinergic wake-promoting systems. | Sequesters G-actin monomers, modulates cell migration and angiogenesis, and upregulates VEGF and myosin transcription. Promotes endothelial differentiation and stem-cell migration to injury sites in preclinical models. |
| Legal status | Schedule IV (US); prescription-only globally; not a supplement | Not FDA approved; research-use-only grey market; banned by WADA |
| WADA status | banned | banned |
| DEA / Rx | Schedule IV | Not FDA approved; not scheduled; research-chemical status |
| Pregnancy | Not recommended | Insufficient data |
| CAS | 68693-11-8 | 885340-08-9 |
| PubChem CID | 4236 | 62707662 |
| Wikidata | Q422968 | Q7799921 |
Safety profile
Modafinil
Common side effects
- headache
- nausea
- anxiety
- insomnia (with late-day dosing)
- dry mouth
- mild blood pressure elevation
Contraindications
- recent myocardial infarction
- unstable angina
- left ventricular hypertrophy
- significant arrhythmia
- history of Stevens-Johnson syndrome
- psychotic disorders
- pregnancy
- concurrent MAOI use
Interactions
- hormonal contraceptives: CYP3A4 induction reduces contraceptive efficacy; use barrier method(major)
- cyclosporine: reduced cyclosporine levels via CYP3A4 induction(major)
- warfarin: CYP2C9 inhibition raises INR(moderate)
- phenytoin: CYP2C19 inhibition raises phenytoin levels(moderate)
- MAOIs: potential hypertensive reaction(major)
- classical stimulants (amphetamine, methylphenidate): additive cardiovascular and sleep-disruption effects(moderate)
TB-500
Common side effects
- injection-site irritation
- fatigue (anecdotal)
- lethargy in early dosing (anecdotal)
Contraindications
- pregnancy
- active malignancy (theoretical angiogenic concern)
- no established human safety profile
Interactions
- BPC-157: Frequently co-administered in anecdotal healing protocols; no controlled interaction data(minor)
Which Should You Take?
Modafinil comes out ahead for most readers on the criteria we weight: 3 catalogued goals, controlled substance, oral dosing, with a Tier-A outcome catalogued. TB-500 is the right call when one of the conditionals below applies.
- → If your priority is wakefulness, pick Modafinil.
- → If your priority is focus or working memory, pick Modafinil.
- → If your priority is post-training recovery, pick TB-500.
- → If your priority is tendon repair, pick TB-500.
Edge case: If you cannot self-administer injections, Modafinil is the only oral option in this pair.
Default choice: Modafinil. Wider use case, a Tier-A evidence outcome catalogued, and broader goal coverage. Reach for TB-500 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 Modafinil and TB-500?
Modafinil and TB-500 differ in category (pharmaceutical vs peptide), mechanism, and typical dosing. See the side-by-side table for full details.
Which has a longer half-life, Modafinil or TB-500?
Modafinil half-life is 13 hours; TB-500 half-life is 2 hours.
Can you stack Modafinil with TB-500?
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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