OBJECTIVES:  To estimate the financial impact of introduction of 5% lidocaine medicated plaster (LMP) monotherapy compared with pregabalin or gabapentin monotherapy, in the Brazilian private healthcare system for the treatment of diabetic polyneuropathy (DPN). METHODS:  Eligible population was calculated for 3 sizes of Health Maintenance Organizations (HMOs): big (>100,000 lives), medium (20,000-100,000 lives), and small (<20,000 lives). Data from National Regulatory Agency for Private Health Insurance and Plans (ANS) was used to obtain the number of patients and extrapolated according to growth rates. Prevalence rates of diabetes and polyneuropathy and percentages of patients in use of antiepileptic drugs were applied to reach the final target population. Direct medical costs and resource use related to disease and adverse events management were estimated annually and based on a Markov model previously developed for cost-effectiveness analysis. Costs of drugs not used in hospitals or ambulatories weren’t included once they aren’t covered. Time horizon had 5 years and 2 market share scenarios were created, one with complete uptake of 5% LMP at the first year, and another with progressive uptake, starting with 40% at the first year and increasing 15% annually until reaching 100%. RESULTS:  Compared with pregabalin, complete uptake of the plaster in one year demonstrated cost saving of 64,457 BRL, 6,727 BRL and 1,065 BRL for big, medium and small HMOs, respectively. Compared with gabapentin, cost saving increased to 1,096,971 BRL, 114,491 BRL, and 18,129 BRL for big, medium and small HMOs, respectively. Scenario of progressive uptake also showed cost saving results for all comparators and HMO sizes. CONCLUSIONS:  The uptake of 5% LMP in Brazilian private healthcare system for DPN treatment can save costs compared with pregabalin and gabapentin. Its use associated with pregabalin also presented this potential for patients non-responders to pregabalin. Savings are attributed to lower adverse event rates.