Inappropriate dental antibiotic prescriptions to prevent infective endocarditis in the United States results in ∼$31 million in excess costs to the healthcare system and patients. This includes out-of-pocket costs ($20.5 million), drug costs ($2.69 million) and adverse event costs (eg, Clostridioides difficile and hypersensitivity) of $5.82 million (amoxicillin), $1.99 million (clindamycin), and $380,849 (cephalexin).