Comparison
Armodafinil vs Magnesium L-Threonate
Side-by-side of Armodafinil and Magnesium L-Threonate. 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.
Armodafinil
Armodafinil is the R-enantiomer sold as Nuvigil. Half-life 10-15 h, 150 mg standard dose, narcolepsy and shift-work approvals, Schedule IV.
Magnesium L-Threonate
Magnesium l-threonate (Magtein) crosses the blood-brain barrier. Typical dose 1,500-2,000 mg. Sleep and cognitive trial data, side effects.
Effects at a glance
Armodafinil
- •FDA approved in 2007 for narcolepsy, shift-work sleep disorder, and OSA residual sleepiness
- •R-enantiomer of modafinil; 150 mg armodafinil is roughly equivalent to 200 mg modafinil
- •Schedule IV controlled in the US; prescription-only globally
- •Longer terminal half-life of about 15 hours produces extended late-day wakefulness coverage
- •Same CYP3A4 induction as modafinil; reduces hormonal contraceptive efficacy
- •Side-effect profile and dermatologic risk warnings mirror modafinil
Magnesium L-Threonate
- •Distinct magnesium salt designed for blood-brain barrier penetration; not a higher-quality systemic magnesium
- •Liu 2010 rodent study: elevated CSF magnesium ~15% and increased hippocampal synaptic density
- •Trial portfolio in humans is small and mostly Magtein-funded; cognitive effects are modest where reported
- •Typical dose 1500 to 2000 mg/day delivers only ~108 to 144 mg of elemental magnesium
- •GI tolerability comparable to other magnesium forms; loose stools in a minority at 2000 mg/day
- •Distinct from magnesium glycinate, which is the conventional sleep/anxiety/repletion form
Side-by-side
| Attribute | Armodafinil | Magnesium L-Threonate |
|---|---|---|
| Category | pharmaceutical | supplement |
| Also known as | Nuvigil, R-modafinil, (R)-(-)-modafinil | Mg-T, MgT, Magtein, magnesium threonate |
| Half-life (hr) ↗ | 15 | 4 |
| Typical dose (mg) ↗ | 150 | 2000 |
| Dosing frequency | daily, morning | 1 to 3 times daily |
| Routes | oral | oral |
| Onset (hr) | 1 | 1 |
| Peak (hr) | 3 | 2 |
| Molecular weight | 273.35 | 294.5 |
| Molecular formula | C15H15NO2S | C8H14MgO10 |
| Mechanism | Weak dopamine reuptake inhibition plus downstream activation of histaminergic, noradrenergic, and orexinergic wake systems; R-enantiomer of modafinil with longer half-life. | Proposed to deliver magnesium across the blood-brain barrier more effectively than other oral salts via threonate-related transporters, raising CNS magnesium and modulating NMDA receptor function and synaptic plasticity. |
| Legal status | Schedule IV (US); prescription-only globally; not a supplement | OTC dietary supplement |
| WADA status | banned | allowed |
| DEA / Rx | Schedule IV | OTC supplement (not scheduled) |
| Pregnancy | Not recommended | Standard magnesium safety; Mg-T-specific data limited |
| CAS | 112111-43-0 | 778571-57-6 |
| PubChem CID | 9148206 | 10691810 |
| Wikidata | Q4791953 | Q27151568 |
Safety profile
Armodafinil
Common side effects
- headache
- nausea
- dizziness
- anxiety
- insomnia (with later-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: additive cardiovascular and sleep-disruption effects(moderate)
Magnesium L-Threonate
Common side effects
- loose stools
- mild GI upset
- headache (rare)
- fatigue (rare)
Contraindications
- severe renal impairment (eGFR below 30)
- hypermagnesemia
- myasthenia gravis (high doses)
- concurrent IV magnesium therapy
Interactions
- tetracyclines and fluoroquinolones: magnesium chelation reduces antibiotic absorption; separate by 2 to 4 hours(moderate)
- bisphosphonates: reduced absorption; separate by 2 hours minimum(moderate)
- muscle relaxants and aminoglycosides: potentiated neuromuscular blockade at high doses(moderate)
- antihypertensives: additive blood pressure reduction at high doses(minor)
Which Should You Take?
Magnesium L-Threonate comes out ahead for most readers on the criteria we weight: 2 catalogued goals, OTC dietary supplement, oral dosing, with a Tier-B outcome catalogued. Armodafinil is the right call when one of the conditionals below applies.
- → If your priority is wakefulness, pick Armodafinil.
- → If your priority is fatigue resistance, pick Armodafinil.
- → If your priority is sleep onset or sleep quality, pick Magnesium L-Threonate.
Edge case: If you want to avoid controlled substance, Magnesium L-Threonate is the more accessible choice.
Default choice: Magnesium L-Threonate. Lower friction to source, and broader goal coverage. Reach for Armodafinil 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 Armodafinil and Magnesium L-Threonate?
Armodafinil and Magnesium L-Threonate differ in category (pharmaceutical vs supplement), mechanism, and typical dosing. See the side-by-side table for full details.
Which has a longer half-life, Armodafinil or Magnesium L-Threonate?
Armodafinil half-life is 15 hours; Magnesium L-Threonate half-life is 4 hours.
Can you stack Armodafinil with Magnesium L-Threonate?
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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