Zyrtec

Anyone’s toddler take Zyrtec? If so how old are they & what are the side effects you experienced if any? My 19m old has been miserable with running nose and goes into coughing fits at night due to drainage. Dr feels it’s allergies and to start her on Zyrtec. I’m very careful what I put in my body so super careful what she takes... it makes me nervous. I’ve read some scary side effects (anger, aggression, irritability) when given to toddlers... (I know, don’t google!). Thanks