Fascinating, so that’s why Merck quietly and voluntarily withdrew Norfloxacin:
The Food and Drug Administration (FDA or Agency) has determined that NOROXIN (norfloxacin) tablets, 400 milligrams (mg), was not withdrawn from sale for reasons of safety or effectiveness. This determination will allow FDA to approve abbreviated new drug applications (ANDAs) for norfloxacin tablets, 400 mg, if all other legal and regulatory requirements are met.
December 12, 2017https://www.federalregister.gov/documents/2017/12/12/2017-26693/determination-that-noroxin-norfloxacin-tablets-400-milligrams-was-not-withdrawn-from-sale-for
For example, norfloxacin (NOR), a fluoroquinolone antibiotic, can act on pathogenic DNA gyrase and hinders bacterial DNA replication (Mathur et al., 2021). NOR is widely used in agriculture, medicine, and other fields, and has been detected in natural water and wastewater (Giger et al., 2003; Costanzo et al., 2005; Tong et al., 2011) and marine species like oysters (He et al., 2019). In a laboratory experiment, short-term exposure to NOR resulted in the homeostasis imbalance of intestinal flora of juvenile large yellow croaker Pseudosciaena crocea, which affected immunity, inhibited metabolism and growth, and even led to death (Wang et al., 2020a). Environmental residues of NOR were immunotoxic to the mussel Elliptio complanata, inducing 10 % mortality, and loss of blood cell viability after 14 days of exposure (Gagne et al., 2012). The occurrence of both antibiotics and plastic particles has been detected in various marine environmental samples (Zheng et al., 2021; Goncalves and Bebianno, 2021). Because of the special characteristics of plastics surface, both MPs and NPs are considered carriers of emerging contaminants antibiotics, modifying their bioavailability and toxicity (Hermabessiere et al., 2017; Amelia et al., 2021). The adsorption ability of NOR on the surface of NPs has been reported, which may be attributed to the hydrophobic interaction (Zhang et al., 2020).https://www.sciencedirect.com/science/article/pii/S004896972301923X
So, I guess, if you want to get your hands on Norfloxacin- just go drink some water.
Toxic to 10% of your red blood cells after 14 days of exposure? That doesn’t sound like a drug that doesn’t target your natural dna gyrase. Although, we’re not fish – maybe it’s just toxic to fish.
We’ll never know because Merck lies about — and gets away with —everything.