I am not a fan of malaria tablets, due to the side effects, and the fact they don't actually prevent you getting malaria. I went to Mumbai about 5 years ago and wasn't bitten but I was wearing anti mosi spray (India actually sells an excellent one which smells of oranges and has a name beginning with O)
We always buy malaria testing kits and take these - then if you feel you have the symptoms, you can do the test and if it's positive you can straight to hospital. Make sure you are aware of the symptoms to look out for otherwise it's pointless.