What is a common clinical use for the drug modafinil?

Modafinil is primarily used to treat narcolepsy, a neurological disorder characterized by excessive daytime sleepiness and sudden sleep attacks. It functions as a wakefulness-promoting agent, helping individuals with narcolepsy to stay awake and alert throughout the day. This use is supported by modafinil's ability to enhance wakefulness and its favorable side effect profile compared to traditional stimulants.

The other options represent conditions where modafinil is not typically indicated. While chronic pain management may involve other types of medications, modafinil is not recognized as an effective treatment for pain relief. Similarly, it is not an anxiolytic medication, so it doesn't function as a treatment for anxiety. Lastly, while there is some interest in cognitive enhancers for dementia, modafinil is not specifically approved or widely used for improving cognitive function in individuals with dementia. Thus, its primary and well-established clinical use remains in the treatment of narcolepsy.