• Subject-rated global impression of change from baseline, after seven days of treatment
  

• Subject global impression of change after 3 days; Proportion of responders after 3 and 7 days, Change from baseline in subject-rated pain intensity, muscle spasm intensity, functional ability, and medication helpfulness after 3 and 7 days.
  

The objective of this multicenter, randomized, open-label, parallel-group, one-week study is to evaluate the effectiveness and safety of cyclobenzaprine HCl 5 mg three times a day for one week, alone or in combination with ibuprofen 400 mg or 800 mg taken three times a day, for acute back or neck muscle pain with muscle spasm. The primary measurement of efficacy is the subject-rated global impression of change after seven days of treatment, compared to baseline. Safety assessments during the study include the monitoring of adverse events, and a physical examination, assessment of vital signs and medical history of any present illnesses conducted during the baseline visit. The study hypothesis is that there will not be a statistically significant difference in patient ratings of global impression of change, muscle spasm, muscle pain, medication helpfulness, and functional ability, between the cyclobenzaprine HCl monotherapy group versus the cyclobenzaprine HCl/ibuprofen 400 mg and cyclobenzaprine HCl/ibuprofen 800 mg groups, for the treatment for acute back or neck muscle pain with spasm. Patients receive cyclobenzaprine HCl 5 mg administered orally three times a day for one week, or cyclobenzaprine HCl 5 mg with ibuprofen 400 mg administered orally three times a day for one week, or cyclobenzaprine HCl 5 mg with ibuprofen 800 mg administered orally three times a day for one week.