Enhanced wakefulness and alertness
Significantly improves wakefulness and reduces fatigue
Modafinil
Prescription wakefulness-promoting agent that enhances alertness and cognitive function without traditional stimulant side effects
Scientific name2-[(diphenylmethyl)sulfinyl]acetamide
FormulaC15H15NO2S
Molecular weight273.35 g/mol
CAS68693-11-8
80
absorption score
8
safety / 10
150
USD per month
5
documented interactions
Check it against something
Modafinil with:
- Amylase
- Ashwagandha
- Avocado Oil
- BCAA (Branched-Chain Amino Acids)
- Beetroot Powder
- Beta-Alanine
- Bifidobacterium lactis
- Bifidobacterium longum
- Bovine Collagen
- Caffeine
- Calcium
- Calcium Bone Formula
- Calcium Carbonate
- Casein Protein
- Chicken Collagen
- Choline (Bitartrate)
- Chondroitin Sulfate
- Coconut Oil
- Collagen Peptides
- Comprehensive Immune Support Complex
- Comprehensive Multivitamin-Mineral Complex
- Creatine HCL
- Creatine Monohydrate
- D-Mannose
- DHA
- Electrolyte Blend
- EPA
- Fish Oil (EPA/DHA)
- Folate (5-MTHF)
- Ginger
- Iron Fumarate
- Iron Sulfate
- Joint Mobility Formula
- Keratin
- Krill Oil
- L-Carnitine
- L-Citrulline
- L-Theanine
- Lactase
- Lactobacillus acidophilus
- Lactobacillus rhamnosus
- Lipase
- Magnesium Citrate
- Magnesium Glycinate
- Magnesium Oxide
- Marine Collagen
- Melatonin
- Olive Oil Extract
- Omega-3 + Curcumin + Vitamin D Triple Anti-Inflammatory Formula
- Papain
- Protease
- Saccharomyces boulardii
- Turmeric
- Vitamin B12 (Cyanocobalamin)
- Vitamin B12 (Methylcobalamin)
- Vitamin C (Ascorbic Acid)
- Vitamin C (Sodium Ascorbate)
- Vitamin D3
- Whey Protein
- Zinc Gluconate
Nothing found
75
out of 100
Works better together
Compatible. Timing differs, so follow each supplement's own window.
What it does
mechanism and evidence for each claimImproved cognitive performance
Enhances focus, concentration, and mental clarity
Extended working capacity
Allows for sustained mental performance without fatigue
Improved executive function
Enhances decision-making and cognitive flexibility
Reduced sleep deprivation effects
Counteracts cognitive impairment from sleep loss
Others take these for the same thing
Same goal, different mechanism — check any of them against this one
Vitamin B12 (Cyanocobalamin)
Energy & nerve support
250-1000 mcg
A
70%
Fish Oil (EPA/DHA)
Heart & brain health
1-2g EPA/DHA
A
85%
L-Theanine
Calm focus & stress relief
100-400mg
B
90%
Vitamin B8 (Inositol)
Mental health & PCOS support
2-18g (condition dependent)
B
95%
SAM-e
Mood support & liver health
400-800mg
A
70%
Lithium Orotate
Mood & brain support
1-20mg
C
60%
Every pair we checked
12 combinations scored by the engine
Modafinil + Caffeine
No documented interaction either way
No known interaction
70
Modafinil + Creatine Monohydrate
No documented interaction either way
No known interaction
70
Modafinil + Calcium Carbonate
No documented interaction either way
No known interaction
70
Modafinil + Whey Protein
No documented interaction either way
No known interaction
70
Modafinil + Lactase
No documented interaction either way
No known interaction
70
Modafinil + Bovine Collagen
No documented interaction either way
No known interaction
70
Modafinil + DHA
No documented interaction either way
No known interaction
70
Modafinil + Turmeric
No documented interaction either way
No known interaction
70
Modafinil + Fish Oil (EPA/DHA)
No documented interaction either way
No known interaction
70
Modafinil + L-Theanine
May reduce potential anxiety and smooth effects
Works better together
75
Modafinil + Vitamin D3
May support energy metabolism and reduce fatigue
Works better together
75
Modafinil + Omega-3 + Curcumin + Vitamin D Triple Anti-Inflammatory Formula
May support brain health and cognitive function
Works better together
75
Dosage
Daily100-200mg
Narcolepsy100-200mg daily
Cognitive enhancement100-200mg daily
Shift work100-200mg before shift
Sleep deprivation100-200mg as needed
Before you take it
Restricted substance. Prescription-only wakefulness agent. Not a dietary supplement.
Pregnancyavoid
When to expect it
First Effects1-2 hours for wakefulness and focus benefits
Peak Benefits2-6 hours for optimal cognitive enhancement
Deficiency DevelopmentNot applicable - synthetic compound
Toxicity OnsetRare with prescribed doses
How to measure it
MarkerModafinil levels (specialized lab)
OptimalTherapeutic levels for prescribed conditions
Deficient belowNot applicable for prescription medication
FrequencyOnly if monitoring for therapeutic drug levels
What actually reaches you
The label counts the carrier, your body does not
Absorption
Very high 80 of 100 · best absorbed form of this compound
Delivered daily
120 mg
Cost per 100 mg delivered
$4.17 comparative — uses the absorption score, not a measured percentage
Works better with
+
L Theanine
May reduce potential anxiety and smooth effects
L-theanine provides calming effects without sedation · level C
+
B Complex Vitamins
May support energy metabolism and reduce fatigue
B-vitamins support cellular energy production · level C
+
Omega 3 Fatty Acids
May support brain health and cognitive function
Complementary brain health benefits · level CWhat not to take with Modafinil
!
Alcohol
May interfere with cognitive benefits and increase side effects
Alcohol impairs cognitive function and may increase toxicity · moderate significance
!
Depressants
May counteract wakefulness effects
Opposing effects on alertness and cognitive function · moderate significanceMedication interactions
Discuss these with a pharmacist before combiningMay reduce modafinil effectiveness
What to do: Monitor effectiveness and adjust dose
Modafinil may affect drug levels
What to do: Monitor drug levels and effects
May reduce contraceptive effectiveness
What to do: Use additional contraceptive methods
Available forms
Modafinil (prescription): Excellent wakefulness, Strong research, Low side effects, Long duration
Food sources
Not found in natural foods
Synthetic pharmaceutical only · N/A
Prescription medications only
100-200mg tablets · 80
Generic versions available
100-200mg tablets · 80
Requires medical prescription
Controlled substance · 80
Too little
- Not applicable (prescription medication):
- Conditions treated by modafinil:
- Excessive daytime sleepiness
- Narcolepsy symptoms
- Sleep apnea-related fatigue
- Shift work sleep disorder
- Cognitive impairment from sleep loss
Too much
- Generally well-tolerated but potential effects:
- Headaches and dizziness
- Insomnia and sleep disturbances
- Anxiety and nervousness
- Nausea and digestive upset
- Rare serious skin reactions
Who benefits most
narcolepsy-sleep-disorders
Primary medical indication for excessive daytime sleepiness
100-200mg daily (prescription)
shift-workers
Helps manage circadian rhythm disruption
100-200mg before shift (prescription)
cognitive-enhancement-professionals
Enhances focus and mental performance for demanding work
100-200mg daily (off-label)
students-exam-preparation
Improves focus and sustained mental performance
100-200mg as needed (off-label)
sleep-deprivation-recovery
Counteracts cognitive effects of sleep loss
100-200mg as needed (off-label)What else affects it
Beyond other supplements
!
Alcohol
May interfere with cognitive benefits and increase side effects
Alcohol impairs cognitive function and may increase toxicityHow it works
- Blocks dopamine reuptake transporter (DAT)
- Increases norepinephrine and dopamine in prefrontal cortex
- Modulates histamine and orexin/hypocretin systems
- Reduces GABA release promoting wakefulness
- Affects adenosine systems reducing sleep pressure
- Enhances executive function through prefrontal cortex optimization
Key findings
what the evidence supports- Excellent evidence for wakefulness promotion and cognitive enhancement
- Superior safety profile compared to traditional stimulants
- Effective for narcolepsy, sleep apnea, and shift work disorders
- Well-documented off-label cognitive enhancement effects
Sources: NIH Examine.com · data reviewed 2026-08-01
Compiled by Denis, who maintains this database and holds no medical qualification — every figure here is sourced or derived, never asserted. How we calculate it →
Common questions
What are the benefits of Modafinil?
Documented effects: Enhanced wakefulness and alertness; Improved cognitive performance; Extended working capacity; Improved executive function. Significantly improves wakefulness and reduces fatigue
How much Modafinil should you take per day?
The common daily range is 100-200mg. By goal — narcolepsy: 100-200mg daily; cognitive enhancement: 100-200mg daily; shift work: 100-200mg before shift; sleep deprivation: 100-200mg as needed.
When is the best time to take Modafinil?
Morning. First effects are typically reported within 1-2 hours for wakefulness and focus benefits.
What are the side effects of Modafinil?
At excessive doses: Generally well-tolerated but potential effects:, Headaches and dizziness, Insomnia and sleep disturbances, Anxiety and nervousness, Nausea and digestive upset. Safety rating at normal doses is 8 out of 10.
What should you not take with Modafinil?
Separate it from Alcohol, Depressants by two to four hours. May interfere with cognitive benefits and increase side effects
Does Modafinil interact with medications?
Documented interactions with cyp3a4-inducers, cyp2c19-substrates, hormonal-contraceptives. Discuss these with a pharmacist before combining.
How do you know if you need Modafinil?
The marker is Modafinil levels (specialized lab), optimal range Therapeutic levels for prescribed conditions. Common deficiency signs: Not applicable (prescription medication):, Conditions treated by modafinil:, Excessive daytime sleepiness, Narcolepsy symptoms.