What is the difference between ADHD and ADD?

ADD was the "old" diagnosis for attention deficit and "hyperactivity" was a separate diagnosis.

A few years ago, the DSM4 (the official diagnostic manual) was changed and ADHD became the official diagnosis with several sub categories inside it. It's all too complicated to write up everything here, so the sub category of ADHD Inattentive is what used to be ADD.

There are also subcategories of Hyperactivity and of Impulsivity.

It's the same thing. check any psychiatrist. 2 names for the same thing. It's just a society's tag. Same brain chemistry, same brain wiring, same behaviour patterns. It's a common misconception that they are different, that ADHD is hypo-active and ADD is hyperactivity, but they are usually dependent on external influences (harsh measures for symptoms etc leading to big reactions). But they are one and the same

ADD=Attention Defecit Disorder ADHD=Attention Defecit Hyperactive Disorder. It's basically the same thing except ADHD defines the kids that can't control their energies. My sister was diagnosed with ADD back when it was first started being researched on, before they had added the hyperactive part. It's pretty true, she's can control the energies in her body but she'll jump from one topic to another like nobodies business and her brain works differently, what may make sense to someone without ADD might not make sense to her because she timed out for a second there while my nephew who was diagnosed with ADHD he has the same symptoms but his energy is all over the place he can't control it.

Hi,
The letter H. ; )

Ok I'll accept the down thumb but I am right just look at the other answers and you can see that the only real difference is a letter. For the most part they are the same thing only with a twitch or two thrown in for effect! Now at least see the humor in the answer or I'll have to go ADD on your @$$.

the truth is none,, the same drugs,,n same treatment,,, people will tell you otherwise though..ADD is the most common diagnoses about 15 years ago, and now, most people now are diagnosed with ADHD

ADHD is when you can't pay atention and is hyper. ADD is when you just can't pay atention.

people with ADHD are usually hyper and can't sit still