OBJECTIVE: To report the first published case of clonazepam-induced burning 
mouth syndrome (BMS).
CASE SUMMARY: A 52-year-old white woman presented to the clinic with burning 
mouth symptoms. The patient was previously maintained on alprazolam therapy for 
anxiety, but was switched to clonazepam because of increased anxiety and panic. 
Clonazepam significantly relieved her symptoms, but after four weeks of therapy, 
she reported a constant, mild, oral burning sensation. An oral examination was 
negative for mucosal abnormalities, and laboratory tests were unremarkable. The 
clonazepam dose was reduced, and the symptoms decreased, but remained 
intolerable. Clonazepam was discontinued, and the burning mouth symptoms 
completely resolved. Since no other medications relieved the anxiety and panic 
symptoms, the patient requested clonazepam to be reinitiated, but she again 
developed intolerable burning mouth symptoms. As clonazepam was discontinued, 
the symptoms resolved.
DISCUSSION: The clinical presentation of BMS includes burning and painful 
sensations of the mouth in the absence of mucosal abnormalities. Candidiasis, 
anemia, menopause, diabetes mellitus, medications, anxiety, and depression are 
some causes of this syndrome. Paradoxically, clonazepam has been studied for the 
treatment of BMS and has demonstrated mild to moderate improvement. In this 
patient, underlying causes of BMS were eliminated when possible. The association 
between clonazepam and BMS was highly probable according to the Naranjo 
probability scale.
CONCLUSIONS: This is the first published report describing BMS with a 
benzodiazepine. Although uncommon, clinicians should be aware of this potential 
adverse effect due to the widespread use of benzodiazepines.