Diovan (Valsartan) is available in different doses (20
mg, 40
mg, etc.), so maybe you could take a lower dose on the day you'll be using Viagra. Or possibly just skip your usual dose that day, then resume the next. However, your Dr. may not agree. I think the best strategy is to ask your Dr. about using these 2 drugs at the same time. I would think if you just took a lower dose on the day you use Viagra might be acceptable...