Plasma levels of milnacipran and its effectiveness for the treatment of chronic pain in the orofacial region

Oral medicine psychiatric liaison clinic: study of 1202 patients attending over an 18-year period

Patients with orofacial pain and discomfort often suffer from psychiatric disorders. However, few studies involving a large sample have examined the diagnostic results of patients with orofacial pain or discomfort in relation to psychiatric disorders. The purpose of this study was to summarize and clarify the characteristics and demographic data of 1202 patients attending the psychiatric liaison clinic at Aichi Gakuin University Hospital. Psychiatric diagnosis was performed by psychiatrists for all patients, based on the Diagnostic and Statistical Manual of Mental Disorders, fifth edition. Among the 1202 patients, 992 (82.5%) were female. The average age of the patients was 57.2±15.0years. The predominant broad categories of orofacial pain and discomfort seen were burning mouth syndrome (n=484, 40.3%), persistent idiopathic facial pain (n=258, 21.5%), and oral dysesthesia (n=215, 17.9%). The predominant broad categories of psychiatric diagnoses seen were somatic symptoms and related disorders (n=934, 77.7%) and depressive disorders (n=76, 6.3%). Among the 934 patients with somatic symptoms and related disorders, 678 had a somatic symptom disorder with predominant pain. The results confirmed that most patients with orofacial pain and discomfort were middle-aged and elderly women suffering from a somatic symptom disorder with predominant pain.

Effect of topical lidocaine in the oral and facial regions on tactile sensory and pain thresholds

OBJECTIVE

The aim of the present study was to examine the effect of lidocaine application to the face, tongue and hand on sensory and pain thresholds of symptom-free subjects.

DESIGN

Eighteen females (mean age 25.7 years, range 22-38) participated. Using Semmes-Weinstein monofilaments, the tactile detection threshold (TDT) and the filament-prick pain detection threshold (FPT) were measured on the cheek skin (CS), tongue tip (TT) and palm side of the thenar skin (TS). Subjects were tested in 2 sessions at a 1week interval in randomised order. Lidocaine (session A) or placebo gel (session B) was applied for 5min. The TDT and FPT were measured before and after application.

RESULTS

The TDT at all sites in session A significantly increased after 5min, but a significant session effect on the TDT was only found at the TT (P<0.01). On the other hand, there were significant session effects on the FPT at all sites (P<0.01).

CONCLUSION

These results indicate that the pain threshold (FPT) is more susceptible to local anesthetics than the sensory threshold (TDT), but further study is needed to use topical lidocaine for the control of oral and facial pain in the clinic.

Five Patients With Burning Mouth Syndrome in Whom an Antidepressant (Serotonin-Noradrenaline Reuptake Inhibitor) Was Not Effective, but Pregabalin Markedly Relieved Pain

Burning mouth syndrome (BMS) causes idiopathic pain or a burning sensation in clinically normal oral mucosa. Burning mouth syndrome is a chronic disease with an unknown etiology. Burning mouth syndrome is also idiopathic, and a consensus regarding diagnosis/treatment has not been reached yet. Recent studies have supported the suggestion that BMS is a neuropathic pain disorder in which both the peripheral and central nervous systems are involved. Tricyclic antidepressants (nortriptyline and amitriptyline), serotonin-noradrenaline reuptake inhibitors (SNRIs) (duloxetine and milnacipran), and antiepileptic drugs, potential-dependent calcium channel α2δ subunit ligands (gabapentine and pregabalin), are currently recommended as the first-choice drugs for neuropathic pain. In this study, we report 5 patients with BMS in whom there was no response to SNRI (milnacipran or duloxetine), or administration was discontinued because of adverse reactions, but in whom pregabalin therapy markedly reduced or led to the disappearance of pain in a short period. Pregabalin, whose mechanism of action differs from that of SNRIs, may become a treatment option for BMS patients who are not responsive to or are resistant to SNRIs.

Temperament and character profiles of patients with burning mouth syndrome

OBJECTIVE

Burning mouth syndrome (BMS) is a chronic disease in which patients feel a burning sensation and pain in the oral cavity. Although personality traits have been suggested to influence the development and course of BMS, they have not yet been examined in detail. We therefore investigated the personality traits of BMS patients.

METHODS

Sample consisted of 65 BMS patients presenting to the Aichi-Gakuin Dental School Hospital between May 2005 and April 2009. They were also diagnosed as having pain disorder by a psychiatrist. The control group consisted of 116 healthy subjects. The Temperament and Character Inventory (TCI) was used to evaluate personality traits, while the Beck Depression Inventory (BDI) was used to evaluate the depression rate in both groups.

RESULTS

In TCI, we found that, in comparison to the control group, the novelty seeking score was significantly lower (p = 0.009), the harm avoidance score was significantly higher (p < 0.001), and the self-directedness score was significantly lower (p = 0.039) in the BMS group. To remove the influence of depression, we performed an analysis of covariance of each TCI item using the BDI score as a covariate. No significant differences were observed in harm avoidance or self-directedness, whereas the differences noted in novelty seeking were significant (p = 0.008).

CONCLUSION

The novelty seeking score was low in BMS patients in comparison to the control group. They also had high harm avoidance and low self-directedness tendencies, but these were attributed to the influence of depression.

Effectiveness of low-dose milnacipran for a patient suffering from pain disorder with delusional disorder (somatic type) in the orofacial region

Glossodynia is chronic pain localized around the tongue, with no perceivable organic abnormalities. In the fields of oral and maxillofacial surgery, it is categorized as an oral psychosomatic disease. In contrast, psychiatric nosology classifies glossodynia as a pain disorder among somatoform disorders, per the DSM-IV. The patient was a 71-year-old woman who developed symptoms of glossodynia, specifically a sore tongue. In the decade before she presented to us, she had had bizarre symptoms of oral cenesthopathy such as the sensation that her teeth had become 'limp and floppy' and that she needles in her mouth. Treatment was attempted using several psychotropic drugs, but no satisfactory response was noted. Because the patient was referred to our outpatient clinic, we tried psychotropic therapy again. Additionally, valproic acid, tandospirone and sertraline were administered (in this order), but the patient still showed no response. However, when sertraline was changed to milnacipran, all symptoms disappeared in a short period. We suggest that a small dose of milnacipran can be effective for controlling oral cenesthopathy as well as glossodynia.