Bitcoin, for now, is not suitable to become a national currency of any country. Bitcoin's value is too volatile so a product or service will always change in price with respect to the price of Bitcoin. Also, a transaction fee is there with every transaction, this is not practical in using in a daily basis. It will be hard for the government to control the scenario. So if a country will make Bitcoin as its national currency then they have to regulate it first.
Bitcoin as a national currency today is not yet applicable. It can affect the market product prices in a negative manner, because of its volatility in its value. The unpredictability of its value will create a huge impact in the market. So bitcoin to become a national currency needs a thorough study by marketing experts and economist.