J.,
ADHD occurs when the neurotransmitters in the brain cannot carry the electrical impulses (we call thoughts) efficiently over the tiny spaces between brain cells called synapses. Brain cells do not actually touch, they have a very tiny spacce between then and our brains make neurochemicals that carry our thoughts from cell to cell, and when that process is interrupted, by a shortage of the chemical, or an inablity of the cells to read the chemical, then that person has ADHD.
It is a physical process. The reason we see hyperactivity in some individuals with ADHD is that they are trying to stimulate themselves, to keep themselves going, kind of like the two year old that does anything to stay awake even though they are really tired. They are under stimulated on the cellular level, just the place that medication works its wonders!
Stimulants work because they imporve the transmisssion of thoughts going from brain cell to brain cell. They have been tested extensively, and are very safe medications. There are many out there to choose from, and one may work better for your son than another. Find a qualified prescriber, and then look for the medication and dosage that will work for him and be willing to ajust the dosage or type of medication as he ages.
All areas of his development are effected if he cannot count on his thought process to work well, this causes all kinds of difficulty as he ages and will cause him to have gaps in his learning in school (no matter how smart he is)and if you think about it, you can see how this affects his behavior too. How would you feel if this is how your brain functioned? Do you think you might be a little irritated? A little defensive? A little angry? Would you resist learning or working on things that you found difficult if you knew that at some point you would just loose track of what you were doing and you did not know when that would happen but knew there was nothing you could do to stop it from happening? (even though everyone else seems to be able to do that, and everyone keeps telling you how smart you are, so why can't you just...you get the idea!)
Try fish oil if you want to, but don't count on it to help his basic disorder, please do not abandon standard treatment unless you find that he cannot tolerate it at all. This is an illness, and there is good medical treatment that works great! It is nothing to be afraid of because he has everything to gain.