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- What is modafinil, and how does it work (mechanism of action)?
- What brand names are available for modafinil?
- Is modafinil available as a generic drug?
- Do I need a prescription for modafinil?
- What are the uses for modafinil?
- What are the side effects of modafinil?
- What is the dosage for modafinil?
- Which drugs or supplements interact with modafinil?
- Is modafinil safe to take if I'm pregnant or breastfeeding?
- What else should I know about modafinil?
What is the dosage for modafinil?
The recommended dose is 200 mg once daily not to exceed 400 mg. It should be administered in the morning for treating narcolepsy or obstructive sleep apnea, and one hour prior to work in those with shift work disorder. It can be taken with or without food. The 400 mg dose may not be more effective than the 200 mg dose.
Which drugs or supplements interact with modafinil?
Modafinil 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 and increased levels of other drugs that leads to their toxicity. Modafinil treatment should be carefully monitored if taken with any of these drugs. Drugs which may have reduced effectiveness if taken with modafinil include cyclosporine (Sandimmune), theophylline, and hormonal contraceptives such as progestin-only or estrogen and progesterone containing drugs (for example, Micronor, Ortho-Novum 1/50). Alternative hormonal contraceptives or an additional non-drug form of contraception should be considered during treatment with modafinil, and treatment should continue for one month after modafinil therapy ends (since the effects of modafinil on contraceptive hormones may continue for several weeks). The effects of modafinil on hormonal contraceptives occurs if the hormones are taken by mouth, patch, or implant.
Drugs that may show increased effects or toxicity if taken with modafinil include warfarin (Coumadin), diazepam (Valium), propranolol (Inderal), imipramine (Tofranil), desipramine (Norpramin), phenytoin (Dilantin) and mephenytoin (Mesantoin).
The effect of alcohol on modafinil has not been adequately evaluated. Alcohol probably should be avoided while taking modafinil.
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