key: cord-0983516-deti33qv authors: López Reboiro, M.L.; Sardiña González, C.; López Castro, J. title: COVID-19 and Argumentum ad ignorantiam or “not everything goes”() date: 2020-06-22 journal: Rev Clin Esp (Barc) DOI: 10.1016/j.rceng.2020.04.007 sha: 9e93b3b74423ca1419b7f3d31afb6e0e1ebdd3e8 doc_id: 983516 cord_uid: deti33qv nan Correspondence COVID-19 y Argumentum ad ignorantiam o «no todo vale» COVID-19 and Argumentum ad ignorantiam or "not everything goes" COVID 19 y "Argumentum ad ignorantiam" o "no todo vale". 1 , which we wholeheartedly endorse, we would like to raise an alarm about a curious process of scientific thinking that, to our understanding, is happening in a generalized manner in the global management of treatment against COVID-19. It is the so called Argumentum ad ignorantiam fallacy, which consists of thinking that "lack of awareness of evidence contrary to an idea that we support counts as evidence in its favor." Nothing is further from the truth, and even more so given the capacity of generating multiple trail-and-error tests with unpredictable consequences, particularly in a disease that we unfortunately still know very little about. Let's look at an example: a recently published preclinical study observed that the anthelmintic ivermectin achieves inhibition of SARS-CoV-2 replication in vitro in 48 hours. 2 As no evidence against it has been published to date, possible theoretical benefits of this drug in humans are to be expected. Nevertheless, if we review the work in detail, it is observed that the dose of ivermectin used in vitro is 5 M. To achieve this concentration in a human being, oral administration on the order of 1,000-1,200 mg of ivermectin would be needed. According to the drug's technical datasheet, the dose tested in humans (healthy volunteers) is around 100-120 mg (single dose) and severe side effects due to intoxication include ataxia and seizures. 3 For this reason, it seems clear that it would not be possible to use this drug to treat SARS-CoV-2 in humans, as the levels required for it to be effective in humans would very probably also be highly toxic. Let's suppose that this drug had been tested at the usual doses approved by the Spanish Agency of Medicines and Medical Devices (AEMPS, for its initials in Spanish) (thus below the therapeutic range for COVID-19) in a health center that had low mortality rates for the disease. In this scenario, it could have falsely been assumed that ivermectin played a decisive role in curing these patients. This is not so, as adequate therapeutic levels in blood would not have been achieved. Therefore, we must be on the alert to publications on "sensationalist" therapies supported by small case series (ozone therapy, vitamin D supplements, etc.) and, sometimes, by doubtful methodology that, supported by the principal of Argumentum ad ignorantiam, promise fantasies of cures for COVID-19 disease. Tomar o no tomar «decisiones en caliente» respecto al tratamiento de la infeccion por SARS-CoV-2 The FDA approved Drug Ivermectin inhibits the replication of SARS-CoV-2 in vitro