• Kanokporn Bhalang D.D.S., M.S., Ph.D.
• Venus Khemkhun
• Apinya Srilekarat
• Lakana Luangjarmekorn D.D.S., M.S.

Objective The aim of this study was to test whether propranolol, a non selective beta-adrenergic
receptor blocker, can reduce clinical pain of patients with Temporomandibular Disorders (TMD).

Materials and methods Four TMD subjects received 2 weeks of propranolol (20 mg/day for the first
week and 40 mg/day for the second week), followed by a 2-week washout period and 2 weeks of
placebo tablets. Pain ratings (average pain, highest pain, lowest pain, and percentage of the time that
subjects had pain) were recorded daily. All subjects and the investigator were blinded to the type of
medication the subjects took at each period. The levels of pain between each period were compared
using Wilcoxon Signed Ranks Test.

Results Forty mg propranolol reduced overall pain ratings in TMD patients while 20 mg propranolol
did not. However, there was no statistically significant difference when the levels of pain during the
propranolol period were compared to those during baseline and placebo periods (p < .05). When
participants were asked to indicated which 2-week period they received test medication, all subjects
identified the period correctly.

Conclusion These preliminary findings of 4 TMD subjects suggest that propranolol can reduce clinical
pain from TMD, although it is not significantly different from placebo.

(CU Dent J. 2005;28:89-98)