It did that to me at first too. I haven't upped the dose at all, and don't take it every day yet, so it hasn't had that effect so much since.
HealthyArtist, who introduced me to pantethine, said that it can do that if you take too much at first. Try to go smaller.
I think it's because it is stimulating to the body. Rise and crash.
The way I take it though, is I get some on the toothpick, hold it with my left hand, in my right hand I hold a piece of chicken with all this fat/broth dripping on it, then I lick it off the toothpick and IMMEDIATELY put the chicken in my mouth and start chewing it and swooshing it all crazy. If I let the pantethine sit on my tongue by itself for a few seconds, it hits me hard and quick, then that crash happens.