evidence: They’re hardly alone. A horse dewormer and treatment for some human parasites, ivermectin was initially promoted, despite the lack of research, as a way to treat or prevent Covid infections. Now it is increasingly being marketed for long Covid, pushed by physicians with ties to political groups spreading anti-vaccine and anti-science messaging. There’s no credible evidence that supports ivermectin’s use for this purpose, and doctors at long-hauler clinics say they frequently see patients who’ve tried the drug without relief. But anecdotes of ivermectin working as a miracle cure swirl around social media, repeatedly referenced on Facebook groups for people suffering from long Covid. [...] FLCCC does not cite specific studies in advocating for ivermectin to treat long Covid, but refers to anecdotal experience: "[I]vermectin is proving to be highly effective at eliminating symptoms based on the rapidly accumulating clinical experiences of the FLCCC and a number of allied experts," reads the website. It describes ivermectin as "one of the safest drugs known," and notes its discovery as a treatment for parasitic infections won a Nobel Prize. Evidence around the drug is grounds for its use "for prevention and treatment in all stages of COVID-19," reads the site. Although ivermectin is relatively safe, it’s far from benign. When taken long term in large doses, it can cause severe rashes, stomach pain, diarrhea, facial or limb swelling, a sudden drop in blood pressure, and liver injury. And even when it doesn’t cause side effects, ivermectin can turn patients away from evidence-based treatments.