Modafinil helps people with narcolepsy to stay awake, review study finds

Modafinil, sold under the brand name Provigil among others, significantly eases excessive daytime sleepiness in people with narcolepsy, according to a new systematic review and meta-analysis.

Across more than a half dozen studies involving nearly 1,000 patients, modafinil was found to increase wakefulness and reduce subjective sleepiness compared with a placebo, confirming the oral therapy’s established short-term effectiveness.

However, the researchers noted that the available evidence is largely based on older clinical trials, with no new controlled studies published in recent years. That limits any ability to assess modafinil’s long-term effectiveness, the team noted.

“These findings confirm the short-term efficacy of modafinil in reducing excessive daytime sleepiness based on legacy randomized controlled trials conducted primarily in the 1990s and early 2000s, while highlighting the absence of new eligible [trials] in the past decade,” the researchers wrote, noting that “long-term safety remains underexplored.”

The team concluded that “long-term efficacy and safety remain to be established, underscoring the need for larger, long-duration randomized trials.”

The study, “An updated systematic review and meta-analysis of modafinil for excessive daytime sleepiness in narcolepsy,” was published in the journal Sleep Medicine: X.

Researchers sought to analyze the effects of modafinil

Narcolepsy is a chronic neurological disorder that disrupts the brain’s ability to regulate the sleep-wake cycle. As a result, people may experience symptoms such as excessive daytime sleepiness, an overwhelming urge to fall asleep during waking hours, and, in some cases, sudden muscle weakness known as cataplexy.

The condition can significantly impair daily functioning, affecting employment, mental health, and personal relationships. It’s often associated with social isolation, stigma, and reduced quality of life.

Thus, “effective management and increased public awareness are crucial to improving both social integration and clinical outcomes for affected individuals,” the researchers wrote.

Modafinil is an oral wake-promoting medication commonly prescribed as a first-line treatment for excessive daytime sleepiness in adults with narcolepsy and other related conditions. It works by helping maintain higher levels of certain brain chemicals that support alertness and cognitive function.

“Multiple studies … have consistently demonstrated the efficacy of modafinil in treating [excessive daytime sleepiness] in narcolepsy, with significant improvements in wakefulness, attention, and overall functioning relative to placebo, and generally good tolerability,” the researchers wrote.

Now, a team led by researchers in India sought to provide an updated assessment of the existing evidence on modafinil’s strengths and limitations in reducing excessive daytime sleepiness. To that end, the researchers conducted a review of published studies evaluating modafinil in adults with narcolepsy compared with a placebo or no treatment.

Most trials testing therapy are more than 20 years old

A total of nine studies, published between 1993 and 2017 and involving 997 patients, were used in the analysis.

Pooled results from five studies involving 750 patients showed that modafinil significantly increased scores on the Maintenance of Wakefulness Test compared with the placebo, indicating improved ability to stay awake.

Similarly, pooled results from four studies involving 690 patients showed that modafinil significantly reduced scores on the Epworth Sleepiness Scale compared with the placebo, reflecting lower levels of subjective sleepiness.

The absence of new randomized trials over the past decade, despite continued reliance on modafinil in clinical practice, underscores a critical gap in long-term and comparative effectiveness evidence rather than a lack of therapeutic relevance.

The researchers emphasized, however, that the available evidence “supporting modafinil is largely derived from trials conducted in the 1990s and early 2000s.”

“The absence of new randomized trials over the past decade, despite continued reliance on modafinil in clinical practice, underscores a critical gap in long-term and comparative effectiveness evidence rather than a lack of therapeutic relevance,” the team added.

Accordingly, the findings of this pooled analysis “should be interpreted as confirming [modafinil’s] established short-term efficacy rather than reflecting recent clinical trial activity,” the researchers wrote.

The team also called for future studies to focus on long-term safety and direct comparisons with newer wake-promoting therapies “to inform personalized therapy for [excessive daytime sleepiness] and to evaluate outcomes beyond alertness, including cognitive performance and psychosocial functioning.”