I had been taking the DDAVP every day for a few weeks to try to help with the dizziness but I do not think it was making a difference so I stopped it and am going to give the Diamox a try. My doctors think I may be having migraine associated vertigo or partial seizures causing this motion sickness type of dizziness. The DDAVP may have been helping the standing symptoms, not sure. The low dose clonidine was a big help for my adrenaline problems but it can cause low BP and my adrenaline is still high when I feel like I am going to pass out or do pass out while sitting or lying down with the dizziness. I hope the new med helps you. BTW, I am never thirsty so it may be more effective for you.