Peripheral edema induced by isosorbide mononitrate in an elderly patient: A case study of dose-related risks and drug interactions.

Abstract

Adverse drug reactions (ADRs) in elderly patients are frequently attributed to age-related altered pharmacokinetics and the complexities of polypharmacy to manage multiple chronic conditions, making elderly patients more susceptible to ADRs. The following is a case report of an 80-year-old female patient with systemic symptoms of chest pain, low blood sugar, mouth ulcers, and concentrates on peripheral edema due to nitrate vasodilator isosorbide mononitrate (ISMN). She had hypertension, diabetes, ischemic heart disease, and chronic obstructive pulmonary disease (COPD).On the third day of therapy, she exhibited peripheral edema, prompting the initiation of furosemide and the cessation of ISMN; the patient's condition markedly improved. ISMN primarily reduces preload by inducing venodilation, which leads to blood pooling and hence peripheral edema. The simultaneous administration of other contributing drugs like antifungal agent fluconazole which can potentiate the ADR by elevating plasma levels of ISMN, leading to an enhanced vasodilatory impact. The evaluation conducted using the modified Schumock and Thornton scale classified the adverse medication response as likely, of moderate intensity, and avoidable. This example emphasizes the need of vigilant monitoring of adverse drug responses in the elderly patients, with importance of dosage modifications as well as highlights cautious prescribing of contributing drugs to prevent ADRs.