Objective: Our objective is to present a case of thyroid abscess complicated by thyroid storm secondary to intravenous drug use. Cases of thyroid abscess causing thyrotoxicosis are rare. This is the first report of thyroid abscess from intrathyroidal injection of illicit drugs resulting in thyroid storm. Methods: We used biochemical evaluation, computed tomography (CT), and ultrasound to assess the thyroid abscess. Treatment included antithyroid drugs, steroids, antibiotics, and surgical drainage. Results: A 28-year-old female presented with neck pain and fever after injecting heroin into her neck. CT showed bilateral thyroid abscesses measuring 3.0 cm on the left and 2.0 cm on the right. Thyroid-stimulating hormone (TSH) was 0.40 mIU/L (reference range is 0.34 to 5.60 mIU/L). She left against medical advice, then returned with worsening symptoms. CT showed multiloculated, bilateral thyroid abscess measuring 8.6 cm on the left and 5.3 cm on the right. She suffered a cardiac arrest and was resuscitated. Her white blood cell count was 25.9 × 103 cells/mL, TSH <0.01 mIU/L, free thyroxine was 4.25 ng/dL (reference range is 0.89 to 1.76 ng/dL), triiodothyronine was 96 ng/dL (reference range is 70 to 204 ng/dL), and thyroid-stimulating immunoglobulin was <89% (reference range is <140%). She had fever, tachycardia, heart failure, and elevated bilirubin confirming a diagnosis of thyroid storm by Japan Thyroid Association criteria and Burch-Wartofsky score. She was treated with propylthiouracil, hydrocortisone, and antibiotics. Two days later her TSH was <0.005 mIU/L, free thyroxine was 3.06 ng/dL, and triiodothyronine was 62.0 ng/dL. Ultrasound showed enlarged, heterogeneous thyroid with loculated fluid collections. Following surgical abscess drainage, her thyroid function normalized and progressed to hypothyroidism. Conclusion: We conclude that thyroid abscess can be a life-threatening complication of intravenous drug use as it can precipitate thyroid storm. Along with surgical drainage of the abscess, successful management includes antithyroid drugs, antibiotics, and steroids to control thyrotoxicosis, infection, and inflammation.