Singed q not working

Every time i press Q, the little buff comes up for a split second but disappears shortly after and I can't see the poison. The poison is invisible but it still comes out, but only for that split second. The only way it works is if I keep hitting Q over and over again, but this is a problem because it drains my mana with each initial Q as well as not making a full stream of poison. It also does not trigger tear of the goddess stacks.