My 3.5 year old son was prescribed Guanfacine for Oppositional Defiance Disorder which was just diagnosed. My son has been incredibly difficult since he was 15 months old. We have had issues with biting, throwing, hair pulling, refusal to get dressed, constant screaming and temper tantrums. Currently, he constantly says "no" to anything he is asked to do (even preferred activities), he is defiant, and he runs wild (he will turn a room upside down in 5 minutes). He can be charming and sweet, but he has a constant motor that never stops. My husband (who is a stay at home dad) is completely exhausted. Our son has injured our 1 year old daughter (he is incredibly jealous and attention seeking). I am interested in exploring medication (in addition to therapy and community activities) but my husband is opposed. Has anyone out there tried Guanfacine for a young child (under 5) and, if so, did you see any improvement? Any problems with side effects? It is difficult to imagine medicating my child, but it is also difficult to get through the day with his constant negativity and impulsive behavior.