An Observation of the Correlation Between ACEI and ARB Medications and Chronic Pain Medication Utilization in a Community Pharmacy.

Bradykinin has shown to affect pain hypersensitivity via reducing the pain threshold when it binds to bradykinin B1 receptors. Bradykinin B1 receptors are upregulated following tissue injury. Thus, any mechanism causing an increase in bradykinin could escalate pain perception. Angiotensin-converting enzyme inhibitors (ACEIs) increase bradykinin by blocking the ACE enzyme from inactivating bradykinin. Angiotensin receptor blockers (ARBs) do not increase bradykinin as much and may not make patients as susceptible to chronic pain by the described expected mechanism. This analysis observed retrospective data from a single community pharmacy to determine if there was a difference between patient groups who chronically used ACEIs and ARBs regarding their use of chronic pain medications. Reports were generated containing all prescription fills of ACEIs and ARBs during the 18-month period and length of therapy was determined from that report per patient. The patients meeting the length of therapy requirements were assessed for pain medication usage to determine presence and length of pain medication therapy. The percentage of patients filling chronic pain medications among chronic ACEI patients was 3.99% higher than chronic ARB patients. This was not statistically different. Other evaluated group differences were not statistically significant.