My elderly mother uses this when she feels tired. She just sprays it a few times (not necessarily 6, maybe only 3 times) under the tongue then lies down for about 15 min. After that time she feels revitalised and gets up, actively looking for things to do. So it's really effective for her. Compare this with the Pure Advantage brand of the B-12 spray (http://www.iherb.com/Pure-Advantage-B-12-500-mcg-Spray-1-fl-oz/18154): that one sends her to sleep! Which actually is also useful, because it works as a sleep aid, esp. when she's in pain. So same supplement, different brands, totally different effects, equally useful.