Modafinil

Trade Names:
Provigil
- Tablets 100 mg
- Tablets 200 mg

Pharmacology

User Reviews & Ratings As a treatment for... Avg User Ratings [?] Shift Work Sleep Disorder 3 reviews Rate it! 9.4 Attention Deficit Hyperactivity Disorder 4 reviews Rate it! 9.0 Multiple Sclerosis 8 reviews Rate it! 9.0 Showing 3 of 8 conditions - Show All... Compare with other drugs.

Wakefulness-promoting agent; however, precise mechanism(s) unknown.

Pharmacokinetics

Absorption

T _max is 2 to 4 h. Food delays T _max approximately 1 h.

Distribution

Apparent Vd is 0.9 L/kg and protein binding is approximately 60%.

Metabolism

Primary site is hepatic via hydrolytic deamination, S-oxidation, aromatic ring hydroxylation, and glucuronide conjugation. Major inactive metabolites are modafinil acid and modafinil sulfone. Modafinil induces it own metabolism via CYP-450 3A4 after chronic administration.

Elimination

Approximately 80% (urine) and 1% (feces) are excreted in 11 days. The half-life is approximately 15 h.

Special Populations

Severe chronic renal failure (CrCl 20 mL/min or less) did not influence the pharmacokinetics, but exposure to modafinil was increased 9-fold.

In patients with severe hepatic function impairment, Cl is decreased approximately 60%, and steady-state concentrations are doubled. Dose reduction is recommended.

Decrease of approximately 20% in oral Cl in patients with a mean age of 63 yr, which is not likely to be clinically important.

Indications and Usage

Improve wakefulness in patients with excessive daytime sleepiness associated with narcolepsy, obstructive sleep apnea/hypopnea syndrome (OSA/HS), and shift work sleep disorder (SWSD).

Unlabeled Uses

Treatment of fatigue associated with multiple sclerosis.

Contraindications

Hypersensitivity to armodafinil, modafinil, or any component of the product.

Dosage and Administration

PO 200 mg/day as a single dose. Patients with narcolepsy or OSA/HS should take the dose in the morning, while patients with SWSD should take the dose 1 h prior to the start of work shift. Consider dosage adjustment for concomitant medications that are substrates for CYP3A4, such as triazolam and cyclosporine.

Consider using a lower dose in this population.

A dose reduction of 50% is recommended.

Storage/Stability

Store tablets at 68° to 77°F.

Drug Interactions

Plasma levels of certain tricyclic antidepressants may be increased.

Plasma levels may be increased by modafinil.

Efficacy may be decreased by modafinil, increasing the risk of unintended pregnancy.

Blood levels may be decreased by modafinil.

Coadministration could alter the plasma levels of modafinil.

May delay the absorption of modafinil.

May have prolonged elimination and may require dosage reduction, as well as monitoring for toxicity.

Use with caution.

Increased risk of phenytoin toxicity.

Triazolam concentration may be decreased, reducing the clinical effect.

Monitor PT.

Laboratory Test Interactions

None well documented.

Adverse Reactions

Cardiovascular

Hypertension (3%); palpitation, tachycardia, vasodilatation (2%).

CNS

Headache (34%); nervousness (7%); anxiety, dizziness, insomnia (5%); depression, paresthesia, somnolence (2%); agitation, confusion, dyskinesia, emotional lability, hyperkinesia, hypertonia, tremor, vertigo (1%); delusions, hallucinations, mania, suicidal ideation (postmarketing).

Dermatologic

Herpes simplex, sweating (1%); serious rash including Stevens-Johnson syndrome and toxic epidermal necrolysis (TEN) (postmarketing).

EENT

Rhinitis (7%); pharyngitis (4%); abnormal vision, amblyopia, epistaxis, eye pain (1%).

GI

Nausea (11%); diarrhea (6%); dyspepsia (5%); anorexia, dry mouth (4%); constipation (2%); flatulence, mouth ulceration, taste perversion, thirst (1%).

Genitourinary

Hematuria, pyuria, urine abnormality (1%).

Hematologic-Lymphatic

Eosinophilia (1%); agranulocytosis (postmarketing).

Hepatic

Abnormal liver function (2%).

Hypersensitivity

Angioedema, hypersensitivity (with rash, dysphagia, and bronchospasm), multiorgan hypersensitivity with death (postmarketing).

Lab Tests

Increased gamma glutamyltransferase and alkaline phosphatase.

Metabolic-Nutritional

Edema (1%).

Musculoskeletal

Back pain (6%); neck rigidity (1%).

Respiratory

Lung disorder (2%); asthma (1%).

Miscellaneous

Flu-like syndrome (4%); chest pain (3%); chills (1%).

Precautions

Pregnancy

Category C .

Lactation

Undetermined.

Children

Safety and efficacy in children younger than 16 yr of age not established.

Elderly

Safety and efficacy have not been established. Because elimination of modafinil and its metabolites may be reduced, consider using a lower dose.

Hepatic Function

Dosage reduction is recommended in patients with severe hepatic function impairment.

CNS

Psychotic episodes have been reported.

CV system

Not recommended for use in patients with history of left ventricular hypertrophy or mitral valve prolapse who have experienced the mitral valve prolapse syndrome when receiving CNS stimulants. Use with caution in patients with a recent history of MI or unstable angina.

Dermatologic reactions

Serious rash, which may be life-threatening or require hospitalization (eg, Stevens-Johnson syndrome, TEN), has been reported in postmarketing experience.

Drug dependence

Because of psychoactive and euphoric effects, modafinil has potential for abuse.

Hypersensitivity

Rarely, serious angioedema and hypersensitivity, with rash, dysphagia, and bronchospasm, have been reported. Multiorgan hypersensitivity (including 1 fatality) has been reported in postmarketing experience.

MI/Unstable angina

Use with caution.

Psychiatric symptoms

Psychiatric adverse reactions have been reported. Postmarketing adverse reactions have included delusions, hallucinations, mania, and suicidal ideation, some resulting in hospitalization.

Wakefulness

May not return to normal in patients taking modafinil.

Overdosage

Symptoms

Aggressiveness, agitation, anxiety, confusion, decreased PT, diarrhea, excitation, insomnia, irritability, nausea, nervousness, palpitations, sleep disturbances, slight to moderate elevations in hemodynamic parameters, tremor.

Patient Information

• Advise patient that medication will not cure sleep disorder and is not a replacement for sleep.
• Advise patient to read patient information leaflet before beginning therapy and to reread it each time medication is renewed.
• Advise patient that medication is taken only once a day.
• Advise patient using modafinil for narcolepsy or OSA/HS to take prescribed dose in the morning to minimize sleep disturbances.
• Advise patient using modafinil for SWSD to take prescribed dose 1 h prior to start of shift work.
• Advise patient to take each dose without regard to meals, but to take with food if stomach upset occurs.
• Advise patient to continue to take previously prescribed treatments (eg, continuous positive airway pressure for patient with OSA/HS) as instructed by health care provider.
• Caution patient not to alter previous behavior with regard to potentially dangerous activities (eg, driving, operating machinery) or other activities requiring appropriate levels of wakefulness until, and unless, treatment with modafinil has been shown to produce levels of wakefulness that permit such activities.
• Caution patient that drug may alter judgment, thinking, or motor skills and to use caution while driving or performing other tasks requiring mental alertness and coordination until tolerance is determined.
• Caution patient that the use of modafinil in combination with alcohol has not been studied, and it is prudent to avoid alcohol while taking modafinil.
• Advise patient to notify health care provider if appetite loss, difficulty sleeping, nervousness, or other bothersome adverse reactions occur.
• Advise patient to stop taking modafinil and immediately notify health care provider if chest pain, mental problems, or rash, hives, or other symptoms of anaphylaxis, angioedema, or other allergic reactions occur.
• Advise women using hormonal contraception (oral, depot, or implantable) to use alternative or concomitant methods of contraception with, and for 1 mo following discontinuation of, therapy.

Link to Page

Print Page

Email Page

Add to List