['temporomandibular disorders']
['propranolol er', 'placebo']

        Inclusion:

          -  Diagnostic criteria for TMD: Group II, Masticatory Muscle Disorders, Myalgia

          -  Facial pain for at least 3 months (and at least 10 of the last 30 days at Visit 0)

          -  Average pain intensity rating ≥30 (0-100 numeric rating scale) over the past week or
             average daily pain intensity rating ≥30 on the same scale on at least 3 days over the
             past week

          -  Agrees to terms for continuing/discontinuing certain prescription/over-the-counter
             pain medications throughout participation

          -  Agrees to not commence new prescription medication, injection therapy, occlusal splint
             therapy or certain other pain management techniques throughout participation

          -  Agrees to limit consumption of alcohol to no more than 7 drinks/week (females) and no
             more than 14 drinks/week (males) throughout participation

          -  If a female of childbearing potential, agrees to use of contraception (licensed
             hormonal method, intrauterine device, condoms with contraceptive foam, abstinence, or
             partner vasectomy) throughout participation

          -  Able to understand and comply with study procedures and provide written informed
             consent

        Exclusion:

          -  History of congestive heart failure or certain cardiac conditions including coronary
             artery disease, uncontrolled hypertension, or hypotension

          -  Bronchial asthma, nonallergic bronchospasm, renal failure or dialysis, diabetes
             mellitus, hyperthyroidism, fibromyalgia, or uncontrolled seizures

          -  Currently taking a β-blocker or certain other medications including haloperidol,
             intravenous verapamil, or reserpine

          -  Currently taking an opioid medication

          -  Daily prescription medication, occlusal splint therapy, or an investigational drug or
             treatment for pain management within past 30 days

          -  Injection therapy or certain other pain management techniques within last 2 weeks

          -  Facial trauma or orofacial surgery within past 6 weeks

          -  Active orthodontic treatment

          -  History of major depression or other psychiatric disorder requiring hospitalization
             within past 6 months

          -  Treatment for drug or alcohol abuse within the last year

          -  Smokes 25 or more cigarettes/day

          -  Currently receiving chemotherapy or radiation therapy

          -  Pregnant or breastfeeding
      