Accelerated hypertension associated with the central nervous system toxicity of metrizamide.

A 68-year-old woman with a history of mild hypertension developed a toxic encephalopathy following myelography with metrizamide. Concomitant with the symptoms of vomiting, headache, muscle twitching, and hallucinations was a sudden and marked increase in arterial pressure. Treatment with parenteral vasodilators caused a partial, but transient lowering of the blood pressure. The mental status abnormalities were resolved by treatment with parenteral lorazempam and, subsequently, the blood pressure returned to the premyelography levels. This report demonstrates that metrizamide can induce a severe, accelerated form of hypertension.