Adverse Drug Reactions Attributed to Fondaparinux and Unfractionated Heparin in Cardiovascular Care Unit: An Observational Prospective Pilot Study in a Tertiary Care Hospital

INTRODUCTION: This study was carried out to collect and analyze the adverse drug reactions (ADRs) reported with use of anticoagulants, heparin and fondaparinux. These drugs are vital in the treatment of unstable coronary artery diseases and emergencies. MATERIALS AND METHODS: A cross-sectional study with active reporting of ADRs from cardiology and medicine department was conducted. The type of reaction was assessed by Rawlins and Thomson criteria, causality by Naranjo probability scale, severity by modified Hartwig criteria, and preventability by Schumock and Thornton criteria. RESULT: Of the 67 patients observed, 16 showed ADRs. Fifteen reactions were attributable to unfractionated heparin and one to fondaparinux following assessment by the Naranjo causality scale. Severity of the ADRs assessed by modified Hartwig criteria showed that although 12 of 16 (75%) were mild, 4 (25%) were moderate in severity. Modified Schumock and Thornton criteria showed that 9 of 16 (56.25%) reactions could not have been prevented whereas 5 (31.25%) were probably preventable and 2 (12.5%) were definitely preventable. CONCLUSION: Incidence of ADRs with fondaparinux was lower than with heparin, hence emphasizing its better safety profile. The study also highlights the need for nurses and other caretakers in the coronary care unit to enquire for and report ADRs, particularly with high-potency medicines that are associated with an equally high potential to induce ADRs.