They last like 6 hours you better have a whole day of nothing to do or else you are just wasteing your money. Dont drink or be stoned out when you take shrooms so you get your money's worth and enjoy the trip. I use a weed grinder to grind up the shrooms untill they are powder like then i just put the powder on my toungue and chase it with a drink that way you can avoid the horrible taste and smell..