Levothyroxine improves subjective sleepiness in a euthyroid patient with narcolepsy without cataplexy.

OBJECTIVE

We discuss the use of levothyroxine for excessive daytime sleepiness (EDS) and prolonged nocturnal sleep time in a euthyroid patient with narcolepsy.

METHODS

After failure of first-line narcolepsy treatments, a 48-year-old female began levothyroxine (25 mcg/day). After 12 weeks of treatment, the patient was evaluated for improvement in total sleep time and subjective daytime sleepiness assessed by Epworth Sleepiness Scale (ESS).

RESULTS

At baseline, ESS score was 16 and total sleep time averaged 16 h/day. After 12 weeks, ESS was 13 and reported total sleep time was 13 h/day.

CONCLUSIONS

Levothyroxine improved EDS and total sleep time in a euthyroid patient with narcolepsy without cataplexy after 12 weeks without side effects.