Viagra is actually a brand itself and is therefore a registered trademark, which may bring you legal troubles in the future. Not only could you lose the domain but you could also be held accountable for damages. Even if one were to disregard the trademark the name is still low quality. If this is a new registration, you should ask for a grace deletion to get at least a portion of your money back. Contact your registrar for more information.
I would recommend avoiding trademarks and doing more research into the industry before registering more names. This will save you money in the long run.