M How long does a GO2 Stick last? Category: GO2 Longer than you think, making them amazing value for money. But let us give you some facts behind the questions. Due to sheer nature of Essential Oils being volatile (not as scary as it sounds, just means that they react to the surroundings) they will oxidate over a period of time. We want to ensure that your GO2 stick is used in its peak period, which is why we would suggest 3 months after opening for maximum performance.