Effect of Tolvaptan on Cognitive Function in Cirrhosis

Baseline assessment will include a 1. battery of eight cognitive tests 2. Health related quality of life 3. MRI head evaluating MR spectroscopy and diffusion tensor imaging Patients will then be given tolvaptan 15-30mg qd for 14 days after which the tests will be repeated. During the first 3 days of tolvaptan administration, patients will be admitted and serum sodium will be drawn every 8 hours. 24 hr urine collection will also be performed. Between the initiation and end of tolvaptan, patients will be seen at least every 3-5 days in between. Participation will be terminated in case patients get transplanted or develop overt HE in between.