This report documents a first unilateral and then bilateral internal jugular vein (IJV) thrombosis as a result of repeated injections of heroin, which is rare in a practice of oral and maxillofacial surgeon. The patient was a 21-year-old male who was referred to a hospital with the diagnosis of phlegmon of the right neck. Emergency non-contrast computed tomography (5 images and 1 Supplemental Video are presented) revealed a hyperattenuating content in the lumen of expanded right IJV which fills its entire length. The patient received initial treatment according to the protocol. Ultrasound (US) (2 images and 2 Supplemental Videos are presented) in a first 24 hours supported the diagnosis describing a case as occlusive acute thrombosis. After 4 days of a positive dynamic the patient was transferred to outpatient mode. In a 10 day US examination (2 images and 2 Supplemental Videos are presented) simultaneously with positive changes in the lumen of a right IJV (partial clot lysis) an appearance of a left IJV thrombosis was noted. Analysis of thrombotic conditions of the neck, diagnostics methods, treatment options, and complications are performed.