Prilocaine Plain, an amide local anesthetic (LA), is somewhat less potent than lidocaine and considerably less toxic after injection into peripheral tissues. Clinically, it produces less vasodilation and is similar to other amide LA in relative freedom from allergic reactions. It is reliably used in a plain solution for cardiac patients receiving short procedures. In this report a patient with a known diagnosis of bacterial endocarditis suffered permanent visual loss in the left eye immediately following dental extraction surgery prior to mitral valve surgery. The clinical implications indicate that the delivery of LA must be done with aspiration before and during the injection. This will possibly prevent intravascular injection, which can lead to fluid emboli occluding the ophthalmic artery with the devastating result of vision loss.