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Modafinil and abnormal bleeding in a young lady with narcolepsy: a case report
Albatol N Rashed1, Ahmed Abdelbasit1, Mana Alshahrani2,3
1Pulmonary Section, Department of Medicine, King Fahad Medical City, Riyadh, Saudi Arabia.
Frontiers in Drug Safety and Regulation
|June 24, 2026
Summary
Stimulant medications like modafinil and methylphenidate may cause recurrent vaginal bleeding in women with narcolepsy type 2. Discontinuation and re-exposure confirmed this rare adverse effect, emphasizing monitoring for hormonal disorders.
Area of Science:
- Neuroscience
- Pharmacology
- Endocrinology
Background:
- Narcolepsy type 2 is a chronic neurological disorder affecting sleep-wake cycles.
- Stimulant medications are commonly prescribed for narcolepsy management.
- Patients with a history of hormonal disorders may have unique responses to medications.
Purpose of the Study:
- To report a rare adverse effect of stimulant medications.
- To investigate the link between modafinil/methylphenidate and vaginal bleeding.
- To highlight the importance of monitoring in specific patient populations.
Main Methods:
- Case report of a 27-year-old woman with narcolepsy type 2, pituitary microadenoma, and multiple sclerosis.
- Observation of vaginal bleeding correlated with stimulant medication use.
- Assessment of symptom changes upon medication discontinuation and re-exposure.
Main Results:
- Recurrent vaginal bleeding occurred during the use of modafinil and methylphenidate.
- Vaginal bleeding resolved after discontinuing both medications.
- Bleeding recurred upon re-initiation of the stimulant medications.
Conclusions:
- Modafinil and methylphenidate can cause rare vaginal bleeding.
- Patients with a history of hormonal disorders require careful monitoring.
- This case underscores potential drug-induced endocrine disruptions.
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