Hydroxychloroquine-Induced Creatine Kinase Elevation

Long-term administration of hydroxychloroquine and chloroquine leads to deposition in the tissues including muscles, nerves and retina. Here, we report a case of hydroxychloroquine induced creatine kinase elevation after loading dose. An 80-year-old man with comorbidities, presented with a dry cough, high fever, diarrhea and general condition disorder ongoing for the last 3 days. The patient was admitted to the intensive care unit. The treatment was commenced with hydroxychloroquine. On the first day of treatment, the loading dose of hydroxychloroquine was started as 400 mg q12h, and treatment was continued as 200 mg q12h from the 3rd dose. After the hydroxychloroquine loading dose, the patient’s creatine kinase level increased, and after drug cessation, the level decreased. Hydroxychloroquine-induced creatine kinase elevated may be on not only long-term use but also acute period. Clinicians should have a high suspicion for hydroxychloroquine toxicity in patients with risk factors.