My 4 month old baby was diagnosed with asthma yesterday. isn't that too young to get it?

Bronchiolitis: At 4 months old wheezing is usually caused by certain viral illnesses and they sound like asthma, but officially you can't really lable them as asthmatic. Having said that many (40-60+%) have wheezing later in infancy and childhood and truly bcome asthmatic. At 4 months the terminololgy is bronchiolitis.

Never too young: People are born with the genetic tendency to develop asthma. Asthmatic symptoms can start anytime after birth. With currently available meds almost all asthmatics can be well controlled and lead a normal life, for example 20% of the last us summer olympic team was asthmatic. Consult an allergist to determine optimal management.

I wouldn't call it: Since about 60% of wheezing in infants disappears by school age I never use it that young and am always suspicious of its use. A kid of 2 asthmatic parents with eczema may eventually be shown to have asthma, but there is so much overlap with those just having infection related wheezing, I just don't call it that young.