Study to Evaluate Two Formulations of Carisoprodol in Subjects With Musculoskeletal Spasm of the Lower Back

Inclusion Criteria: * Onset of pain is within 3 days of first visit * Subject rating of pain must be 40 mm or greater on VAS * Ability to discontinue all analgesics, NSAIDs, and other muscle relaxants * Willingness to provide written informed consent * Must be in generally good health Exclusion Criteria: * Presence of sciatic pain * History of clinically significant spine pathology such as herniated nucleus pulpous, spondylolisthesis, spinal stenosis * Presence of underlying chronic back pain * Neurological signs and symptoms such as numbness, tingling, foot drop, paresthesia, unexplained constipation, urinary retention or urinary incontinence * Myocardial infarction within one year of study * Cancer not in remission or in remission less than one year * HIV or other immunodeficiency syndromes * History of osteoporosis or at high risk for vertebral fracture * Underlying rheumatologic disease such as rheumatoid arthritis, ankylosing spondylitis, etc. * Presence of active influenza or other viral syndromes * Morbid obesity (BMI \>39) * Evidence of infection, such as low grade fever or neutrophilia * Existence of any medical/surgical condition that could interfere with the evaluation of the study medication * Known history of alcohol or drug abuse * Injury involving high potential for litigation, including worker's compensation or automobile accidents * Pregnancy or breast feeding * Women of child-bearing potential not abstinent or not practicing a medically acceptable method …