Adverse drug reactions in hospitalized psychiatric patients.

Background: Reducing adverse drug reactions (ADRs) is a critical element in providing safe medication use to hospitalized patients. There is an abundance of literature describing ADRs and preventable ADRs (pADRs) in hospitalized patients; however, little has been published specific to psychiatric inpatients. Further knowledge of the most common pADRs in hospitalized psychiatric patients will allow targeted patient safety initiatives to be developed.

Objective: To determine the most frequent ADRs and pADRs in a psychiatric hospital, with emphasis on identifying factors for prevention.

Methods: Three years of ADRs at a psychiatric hospital were analyzed and evaluated according to type of medication, preventability, severity, and factors associated with preventability.

Results: From July 1, 2006, to June 30, 2009, 93 ADRs were reported; 19 (20.4%) were classified as preventable. Psychiatric medications accounted for 45 (48.4%) of the ADRs and nonpsychiatric medications were associated with 48 (51.6%). Cardiovascular agents (n = 17) and antiepileptics (n = 17) were responsible for most ADRs. Of the 19 pADRs, lithium was the drug reported most frequently, followed by phenytoin and anxiolytics. Nine (47%) of the pADRs were severe and required a medical transfer for management; 3 of the 9 were lithium toxicity. The most common preventability factor involved drug interactions. A pharmacy intervention involving staff education to reduce lithium pADRs is presented.

Conclusions: Awareness of the most frequent drug classes associated with ADRs and pADRs in a psychiatric hospital allows opportunity for education, medication management system changes, and improved patient safety. Lithium, followed by phenytoin and anxiolytics, were the most common drugs associated with pADRs. A drug-drug interaction was the most frequent factor associated with pADRs.