Comparison
Ashwagandha vs Modafinil
Side-by-side of Ashwagandha and Modafinil. 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.
Modafinil
Modafinil cognitive enhancement profile: wakefulness-promoting agent, 100-200 mg dosing, 12-15 hour half-life, off-label nootropic use, Schedule IV status.
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
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
Side-by-side
| Attribute | Ashwagandha | Modafinil |
|---|---|---|
| Category | natural | pharmaceutical |
| Also known as | Withania somnifera, KSM-66, Sensoril | Provigil, Modalert, Modvigil, diphenylmethylsulfinyl-acetamide |
| Half-life (hr) ↗ | 10 | 13 |
| Typical dose (mg) ↗ | 600 | 200 |
| Dosing frequency | daily | daily, morning |
| Routes | oral | oral |
| Onset (hr) | 2 | 1 |
| Peak (hr) | - | 3 |
| Molecular weight | - | 273.35 |
| Molecular formula | - | C15H15NO2S |
| Mechanism | GABAergic modulation and HPA-axis attenuation; withanolides reduce cortisol secretion and inhibit NF-kB signaling. | Weak dopamine reuptake inhibition plus downstream activation of histaminergic, noradrenergic, and orexinergic wake-promoting systems. |
| Legal status | Dietary supplement in most jurisdictions; regulated in Denmark | Schedule IV (US); prescription-only globally; not a supplement |
| WADA status | allowed | banned |
| DEA / Rx | OTC supplement | Schedule IV |
| Pregnancy | Not recommended | Not recommended |
| CAS | - | 68693-11-8 |
| PubChem CID | - | 4236 |
| Wikidata | Q310109 | Q422968 |
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)
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)
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. Modafinil 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 hormonal optimization, pick Ashwagandha.
- → If your priority is wakefulness, pick Modafinil.
- → If your priority is fatigue resistance, pick Modafinil.
Edge case: If you want to avoid controlled substance, Ashwagandha is the more accessible choice.
Default choice: Ashwagandha. Lower friction to source, and broader goal coverage. Reach for Modafinil 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 Modafinil?
Ashwagandha and Modafinil differ in category (natural vs pharmaceutical), mechanism, and typical dosing. See the side-by-side table for full details.
Which has a longer half-life, Ashwagandha or Modafinil?
Ashwagandha half-life is 10 hours; Modafinil half-life is 13 hours.
Can you stack Ashwagandha with Modafinil?
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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