Was arsenic ever used to treat Lyme disease?

Yes, arsenic was historically used in the treatment of various diseases, including Lyme disease, particularly in the late 19th and early 20th centuries. However, it is not considered a standard or effective treatment for Lyme disease today. Modern treatments primarily involve antibiotics, which have proven to be more effective and safer. The use of arsenic for medicinal purposes has largely been abandoned due to its toxicity and potential side effects.