
    we were unable to enroll any patients into the study.
  
['osteoarthritis', 'rheumatoid arthritis', 'avascular necrosis']
['placebo', 'lacosamide']

        Inclusion Criteria:

          -  Patients will be eligible for participation if they are 18-70 years of age.

          -  Patients who have an American Society of Anesthesiologists physical status I-III.

          -  Patients who are scheduled for primary total hip arthroplasty.

          -  Any patients who are willing to comply with study requirements and agrees to be in the
             study.

        Exclusion Criteria:

          -  A patient's refusal to participate.

          -  Inability to give consent.

          -  Any patients on a scheduled opioid regimen for pain greater than 3 months.

          -  Bleeding diathesis.

          -  Hypersensitivity to lacosamide or any component of the formulation (some formulation
             contains phenylalanine) and/or any drug allergies to any medications used in this
             study.

          -  Second- or third-degree atrioventricular (AV) block, sick sinus syndrome without
             pacemaker, sodium channelopathies (e.g., Brugada syndrome), myocardial ischemia, heart
             failure, and structural heart disease.

          -  Severe hepatic and or renal impairment.

          -  Pregnant or can become pregnant.

          -  Breast-Feeding.

          -  Have any suicidal thoughts, depression, or behavioral changes.

          -  Taking any antiepileptic medications.

          -  Any known seizure disorder (e.g. Lennox-Gastaut syndrome).

          -  Currently prescribed:

        Carbamazepine Strong inhibitors of cytochrome P450-2C9 (Capecitabine; Delavirdine;
        floxuridine; Fluorouracil (Systemic); Gemfibrozil; Nicardipine; Sitaxentan; Sulfadiazine;
        Sulfissoxazole; Tegafur; Tolbutamide) Strong inhibitors of cytochrome P450-3A4 (Atazanavir;
        Boceprevir; Chloramphenicol; Clarithromycin; Cobicistat; Conivaptan; Darunavir;
        Delavirdine; Fosamprenavir; Indinavir; Itraconazole; Ketoconazole (Systemic); Lopinavir;
        Nefazodone; Nelfinavir; Nicardipine; Posaconazole; Ritonavir; Saquinavir; Telaprevir;
        Telithromycin; Voriconazole) Delavirdine Fosphenytoin Nicardipin Phenobarbital Phenytoin
        Ethinylestradiol
      