If it is used correctly it works great. Here what I do: first I spray saline which is a product from otrivin and it is made just with sea water and can be used as of 2 weeks old according to this product instructions. Whatever product you use make sure you resect yur baby's age. Than right away I use the aspirator according with its instructions. Never use the aspirator without moisturising baby's nose, first the aspirator will not be efficient so you would basically need to pomp several times which can hurt the baby's nose and second you would stress the baby.