Author(s): T Cooksley, P Haji-Michael Format Abstract Posterior reversible encephalopathy syndrome (PRES) is a combined clinical and radiological syndrome characterised by headaches, encephalopathy, seizures and visual loss. We present the case of a 55-year-old male who developed this condition following treatment with deoxycoformycin and alemtuzumab. We review the literature considering diagnosis, pathophysiology and optimal strategies for treatment of this condition. Keywords Chemotherapeutic agents, encephalopathy, headache, PRES, seizures Declaration of Interests No conflict of interests declared. PDF https://www.rcpe.ac.uk/sites/default/files/cooksley.pdf Journal Keywords: Chemotherapeutic agentsencephalopathyheadachePRESseizures