K., as someone already said, you need, first of all, to establish if your son does, in fact, have ADD/ADHD. You mentioned your parents put you on meds when you were young. Was this for ADD? The condition does run in families and one of the keystones doctors look for in children with ADD is if a parent has the condition.
It is entirely possible your son has some other disorder or is just a temperamental kid trying to find his place and identity by testing his limits and emulating others (the potty mouth at daycare, for example.) And bear in mind, it could just be that your kids are so different, he seems to be hyperactive by comparison.
There is a readily traced line of ADD in my family and I know the problems it can cause, from lack of attention to being overly attentive (hyper-focus on something).
Does your son have a difficult time taking orders or following instructions? If so, make sure you get his undivided attention and make eye contact when you talk to him.
Don't give him too many tasks at one time. At the age of 4, one at a time is probably all he can handle. As he gets older, 6 or 8, double the load but never more than 3 things at a time. That seems to be about the attention span limit for us! When he gets older, get him in the habit of writing things down he needs to remember.
There are many alternatives to medication and many ways of dealing with ADD. There are also a number of websites dedicated to the issue.
Remember, in the case of ADD's - patience isn't just a virtue, it's an absolute necessity!
Good luck to you.