It like impossible for bitcoin to inflate because of the blockchain technology behind it and the fact that it can not be falsified. In many aspects it's more valuable than gold and that says something. Bitcoin is stable and it's here to stay, i think forever.
As a general rule, inflation happens when new money is released. New Bitcoin is released everytime a block is mined, so Bitcoin absolutely suffers from inflation, as others have said. USD's 2017 inflation stands at around 2.1%, while Bitcoin's is at 3.9%, but Bitcoin's will be increasingly lowered every halving, and will eventually flip to deflation once all coins have been mined.
Either way, it's not much of a problem. People seem to be much more worried about the eventual deflation, which carries concerns towards its utility as a currency.