most mammals make their own taurine. However, cats do not and that is why they catch and eat mice which are high in taurine.

Without taurine they die. Kittens born to mothers low in taurine can be blind or have severe neurological damage if they do survive.

Commercial cat foods all have taurine added to them. This is why there is a warning to not feed dog food to cats, because there is no added taurine in that food.

So if people fail to make their own taurine because of an external event (trauma, genetic, or infections etc) then using
taurine supplements is necessary.

Taurine is in some energy drinks:
Ingredients - What is in Red Bull? Composition :: Energy Drink :: Red Bull USA

The response to the taurine should start in about a week. I was already taking 500mg for my gall bladder so my response was quick when I raised the dose to 1000mg a day. You may need to take a bit more depending on your circumstances, but don't raise up until a month or so passes. I don't have any negative side effects from it at all.