Objective: to estimate whether combination of ibuprofen and paracetamol is more effective than ibuprofen in monotherapy, in the treatment of acute low back pain. Methods: 80 adult patients with acute low back pain were randomized into two subgroups. In the first subgroup, 40 patients were treated with ibuprofen 400mg three times a day (TID), whilst patients in the second subgroup (n=40) were treated with a fixed-dose combination tablet of ibuprofen 200mg plus paracetamol 325mg TID, for three consecutive days. Patients were followed for another 7 days. Efficacy and tolerability of both treatment options was assessed. Results: A statistically significant decrease in pain intensity, assessed using a visual analogue scale (p