A 35 year old patient is sent home with his first episode of

severe gout of hit first MTP joint on the right foot. He filled his

prescription at the local chemist. He returns 5 days later with his wife due to

aggression, irritability and insomnia. His wife tells you he has bipolar disorder which has been well controlled for a long time. She has never seen him like

this before.

You think it might be due to the medications he was sent

home with for his gout.

Which of the following medication is likely to be the cause?