Correspondence (letter to the editor): Oral Fosfomycin—Supplemental Information Necessary

This review gives general therapy recommendations, including for oral fosfomycin, for which it lists heart failure as one of the dangerous adverse reactions of the active substance (1). As they stand, these points are ambiguous, to say the least, and require clarification. Table 1 of the review lists oral fosfomycin. However, the oral delivery form of the substance is only approved for the treatment of uncomplicated urinary tract infections (2). Infection by 3/4 multiresistant Gram-negative (MRGN) pathogens are not considered to be straightforward, and oral fosfomycin is inappropriate for treating systemic infections due to its poor absorption and its resulting low levels in tissues. In contrast, intravenous fosfomycin achieves high therapeutic levels and, according to the current S2k guideline of the Paul Ehrlich Society for Chemotherapy, represents an important therapeutic option in the combination therapy of 3/4 MRGN, especially in intensive care (3). However, it is not listed by the authors in the treatment recommendations given in Table 2. Thus, a relevant therapy option remains hidden. Listing heart failure in the text as a dangerous adverse event of the drug is also misleading. Heart failure as a direct adverse event of fosfomycin is not documented either in the summary of product characteristics or in current reviews on drug safety (4). In summary, the authors unfortunately did not adequately differentiate between the different areas of use for oral and intravenous administration of fosfomycin. Only intravenous fosfomycin should be listed as a treatment option for 3/4 MRGN infections.