A 44-year-old woman, who was suffering from widespread
musculoskeletal pain,
fatigue, and
sleep disorder, was diagnosed as
fibromyalgia. There was no apparent organic disease.
Duloxetine therapy was introduced with a dose of 60 mg/day at bedtime. A few days later her husband noted severe teeth clenching and associated loud grinding noises during sleep. Then,
duloxetine dosage was reduced to 30 mg/day. The
bruxism continued with this dosage, thus the
therapy was discontinued. The
bruxism resolved after cessation. Three weeks later,
duloxetine therapy was restarted at the dosage of 60 mg/day. On the third day of the
therapy,
bruxism started again and
amitriptyline therapy at the dosage of 10 mg/day was added to
duloxetine therapy. The dosage of
amitriptyline was incrementally adjusted to 25 mg/ day. On the fourth day of the combined
therapy,
bruxism symptoms improved. Two months later, the
bruxism symptoms were resolved and the complaints for
fibromyalgia were under control. Although
bruxism has been reported due to
venlafaxine use, there is only one
duloxetine-induced
bruxism case in the literature which was treated with
buspirone. However, we report
duloxetine-induced
bruxism treated successfully with
amitriptyline in a patient with
fibromyalgia.
Tricyclic antidepressants have a suppression effect on the REM phase of the sleep cycle; this may help to cease the
bruxism symptoms appearing in that phase of the sleep cycle. This is the first reported case of
fibromyalgia with
duloxetine-induced
sleep bruxism successfully treated with
amitriptyline.