What is armodafinil, and how does it work (mechanism of action)?

Armodafinil is an oral drug that is used to promote wakefulness. It is similar to modafinil (Provigil). Like amphetamines, armodafinil promotes wakefulness by stimuatIng the brain; however, the exact mechanism of action of armodafinil is unknown. Armodafinil may work by increasing the amount of dopamine (a chemical neurotransmitter that nerves use to communicate with each other) in the brain by reducing the reuptake of dopamine into nerves.

What are the side effects of armodafinil?

Headache is the most common side effect of armodafinil. Other side effects include:

anxiety,
dizziness,
diarrhea,
dry mouth,
insomnia,
nausea,
fatigue, and
rash.
Rare side effects include angioedema, difficulty swallowing, bronchospasms, and reversible psychosis.

Which drugs or supplements interact with armodafinil?
Armodafinil can decrease or increase the activity of enzymes in the liver that metabolize (eliminate) other drugs. This can result in decreased levels of some drugs that reduce their effectiveness as well as increased levels of other drugs that increase their toxicity. Armodafinil treatment should be carefully monitored if taken with any of these drugs.

Drugs which may have reduced effectiveness if taken with armodafinil include cyclosporine (Sandimmune), ethinyl estradiol (Estrace, Climara, Estraderm, Menostar) (present in many birth control pills), midazolam (Versed), and triazolam (Halcion).

Drugs that may show increased effects or toxicity if taken with armodafinil include omeprazole (Prilosec), warfarin (Coumadin), diazepam (Valium), propranolol (Inderal), imipramine (Tofranil), desipramine (Norpramin), clomipramine (Anafranil), phenytoin (Dilantin) and mephenytoin (Mesantoin).

Carbamazepine (Tegretol), phenobarbital, and rifampin (Rifadin) may reduce the action of armodafinil by increasing armodafinil's elimination by the liver. Ketoconazole (Nizoral), itraconazole (Sporanox) and erythromycin may increase the effectiveness of armodafinil by reducing the elimination of armodafinil by the liver.