Pregabalin and amitriptyline as monotherapy or as low-dose combination in patients of neuropathic pain: A randomized, controlled trial to evaluate efficacy and safety in an Eastern India teaching hospital

Abstract

Objectives: The main objective is to compare efficacy and safety of pregabalin and amitriptyline monotherapy with their low-dose combination in patients of neuropathic pain (NeuP). Methodology: In this parallel-group, open-label interventional study at the Neurology Outpatient Department of Bankura Sammilani Medical College, a total of 147 patients were randomly allocated into three groups and were prescribed the following drugs – Group P (n = 42) pregabalin 150 mg once daily, Group A (n = 34), amitriptyline 25 mg once daily, and Group Z (n = 37) = pregabalin (75 mg) + amitriptyline (10 mg) as combination once daily. They were followed up after 4, 8, and 12 weeks. Efficacy was assessed by NeuP symptom inventory score (NPSI) and safety was assessed by treatment-emergent adverse events. Results: Final assessment was done on 92 patients (P = 31, A = 31, Z = 30). Males were predominant (71.7%). NPSI score significantly decreased in every group from baseline (P < 0.0001). There was no difference of NPSI score between groups at any level of follow-up. Percentage of adverse drug reactions were maximum (44.9%) in amitriptyline monotherapy group and lowest in combined group. However, amitriptyline monotherapy was the cheapest treatment option among these three. Conclusion: Combining pregabalin and amitriptyline at low doses proved to be equally effective but more tolerable compared to individual higher dosage monotherapy. However, if tolerability is good, amitriptyline monotherapy can be an attractive choice in economically challenged group of patients.

Keywords

• amitriptyline
• controlled trial
• low-dose combination therapy
• neuropathic pain
• pregabalin
• randomized