Valproate-induced burning mouth syndrome in a male with fibromyalgia and bipolar spectrum disorder

Burning mouth syndrome is a chronic painful condition characterized by a subjective intraoral pain and burning sensations in the absence of an identifiable medical, dental, or psychiatric cause. Although the underlying etiology is currently unclear, an idiopathic (or primary) form and a secondary form to other conditions are formally recognized. However, as several authors have suggested, it might be of clinical utility to consider the existence of a third clinical entity, namely Drug-Induced Burning mouth syndrome, for its therapeutic implications. The latter has been reported with angiotensin-converting enzyme inhibitors, angiotensin receptor blockers, antiretrovirals, anticoagulants, chemotherapy, and drugs commonly used in the treatment of neuropsychiatric disorders such as antidepressants, benzodiazepines, and antipsychotics. Regarding anticonvulsants a literature search found a previous case of Topiramate-Induced Burning mouth syndrome but no previous report of valproate-induced Burning mouth syndrome. Our case is, to date, the first case in the literature of Burning mouth syndrome onset following the administration of valproate to a patient suffering from fibromyalgia and bipolar spectrum disorder. Symptoms resolved completely when the drug was stopped, and the association between symptoms and drug was replicated after drug re-administration.