OBJECTIVES: To examine adherence to medications used in managing painful diabetic peripheral neuropathy (PDPN) and determine their association with oral antidiabetic medication (OAD) adherence. METHODS: A retrospective cohort analysis using the Texas Medicaid prescription claims database. Study participants were adult (30-64 years) Medicaid beneficiaries prescribed OAD and PDPN medications. Data were extracted from June 1, 2003 to October 31, 2009. The study’s research objectives were to : 1) provide a description of PDPN and OAD medication use among the study subjects; 2) determine if PDPN medication adherence differs among individual PDPN medication (i.e., TCAs, gabapentin, pregabalin and duloxetine); and 3) determine if PDPN medication adherence is related to post-index OAD medication adherence while controlling for covariates. Adherence was measured using medication possession ratio (MPR). RESULTS: A total of 4277 patients met the study’s inclusion criteria. The overall mean MPR (±SD) for PDPN medications was 75.4% (±23.9%). Mean MPR differed significantly among individual PDPN medications (p<0.0001). Mean MPR was highest for duloxetine (85.6%±18.2%) and was lowest for pregabalin (69.4%±24.9%). The overall mean MPR (±SD) for OAD medications decreased significantly (p<0.0001) from 73.0% (±24.3%) in the pre-index period to 64.5% (±25.6%) in the post-index period. After controlling for covariates, non-adherers (i.e., MPR<80%) to PDPN medications, compared to adherers (i.e., MPR≥80%), were significantly less likely to be adherent to OAD medications [Odds Ratio (OR) =0.626; 95% CI=0.545-0.719]. CONCLUSIONS: Patients’ adherence to PDPN medications was associated with adherence to OAD medications. Patients who were adherent to PDPN medications were more adherent to OAD medications.