Purpose of Review <p>Infusion reactions from amphotericin B formulations are common and frustrating for patients and providers alike. These may lead to drug discontinuation and alternative agents sought with different toxicity profiles. This review provides a detailed assessment of the incidence and mechanisms behind these reactions.</p> Recent Findings <p>Lipid formulations of amphotericin B provide less nephrotoxic alternatives to amphotericin B deoxycholate, however the molecular mechanisms behind infusions reactions have only recently been assessed in patients receiving these agents. Assessments of both pediatric and adult patients have found non-IgE mediated reactions are responsible for the majority of infusion-reactions with activation of the complement system the primary cause. This syndrome, termed complement activation-related pseudoallergy (CARPA) is responsible for the observed symptoms and hemodynamic changes seen during infusion of these agents.</p> Summary <p>This review compares the incidence and type of infusion-reactions observed with different amphotericin B formulations, examines the molecular mechanisms responsible, and provides recommendations on prophylactic strategies to mitigate these reactions.</p>