Introduction: Hyaluronic Acid (HA) used in aesthetic procedures is of animal or bacterial origin, differing from human HA, interfering with its solubility and metabolization, and may cause emboli to form. This article reports the case of a patient with a patent foramen ovale who suffered a stroke after a penile harmonization procedure with Hyaluronic Acid. Methods: The case reported in this article was collected through the evaluation of medical records and interviews with the respective patient, and we evaluated the results considering the most recent literature. Results, Discussion and Conclusions: A 51-year-old man developed holocranial headache and tonic-clonic seizure after 40 minutes of glans plasty with hyaluronic acid. On physical examination, the patient had bilateral homonymous hemianopsia, worse on the left, magnetic resonance imaging showed areas of restriction to occipital diffusion bilaterally, more to the left, Doppler ultrasound of the skull showed a high conductance right-to-left shunt and transesophageal echocardiography showed a foramen patent oval, opting for anticoagulation. Negative results are generally caused by inadequate intravascular application, the interaction with HA causes chemical damage to the intimal vascular layer and activation of coagulation factors leading to venous obstruction and thromboembolus formation. In general, glans fillers are safe, but anatomical variations and the characteristics of HA can lead to complications.