A-Z Drug Facts > Modafinil

Modafinil

Pronouncation: (moe-DAFF-ih-nill)
Class: Analeptic

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

Alertec (Canada)

Pharmacology

Feedback for Modafinil As a treatment for... Avg User Ratings [?] Multiple Sclerosis 9.5 2 comments  Rate it! Obstructive Sleep Apnea/Hypopnea Syndrome 9.0 1 comments  Rate it! Narcolepsy 8.7 7 comments  Rate it! Showing 3 of 4 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 t _½ is approximately 15 h.

Special Populations

Hepatic Function Impairment

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

Indications and Usage

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

Unlabeled Uses

Treatment of fatigue associated with multiple sclerosis.

Contraindications

Standard considerations.

Dosage and Administration

Adults and Children (16 yr of age and older)

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

Elderly

Consider using a lower dose in this population.

Hepatic function impairment

A dose reduction of 50% is recommended.

Storage/Stability

Store tablets at controlled room temperature (68° to 77°F).

Drug Interactions

Certain tricyclic antidepressants (eg, clomipramine, desipramine)

Plasma levels of certain tricyclic antidepressants may be increased.

Clomipramine

Plasma levels may be increased by modafinil.

Contraceptives, oral

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

Cyclosporine

Blood levels may be decreased by modafinil.

MAOIs (eg, isocarboxazid)

Use with caution.

Methylphenidate

May delay the absorption of modafinil.

Phenytoin

Increased risk of phenytoin toxicity.

Triazolam

Triazolam concentration may be decreased, reducing the clinical effect.

Warfarin

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, emotional lability, paresthesia, somnolence (2%); anxiety, confusion, dyskinesia, hyperkinesias, hypertonia, tremor, vertigo (1%); symptoms of mania or psychosis (postmarketing).

Dermatologic

Sweating, herpes simplex (1%).

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, thirst, (1%); taste perversion (1%).

Genitourinary

Hematuria, pyuria, urine abnormality (1%).

Hematologic-Lymphatic

Eosinophilia (1%); agranulocytosis (postmarketing).

Hepatic

Abnormal liver function (2%).

Lab Tests

Increased gamma glutamyltransferase and alkaline phosphatase.

Metabolic-Nutritional

Edema (1%).

Musculoskeletal

Back pain (6%); neck pain (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.

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 mitral valve prolapse syndrome when receiving CNS stimulants.

Drug dependence

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

MI/Unstable angina

Use with caution.

Wakefulness

May not return to normal in patients taking modafinil.

Overdosage

Symptoms

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

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 OSAHS 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, CPAP for patient with OSAHS) as instructed by health care provider.
• Caution patients 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.
• Advise patient to take medication as prescribed and to not stop taking or change the dose unless advised by health care provider.
• 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, nervousness, difficulty sleeping, 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 an allergic reaction 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 this page

Printable Version

Email Page

Add to my drug list