I think, in general, doctors always try to figure out the best solutions for patients, although this can be tricky as each patient is unique and they only have published studies of large groups and their own experience to help them make decisions. Then again, I think it is always important not to treat what a physician says as the word of God. Do as much research as you can and try to form your own opinions based both on what you learn on your own as well as what your doctor says. Personally, I would put more weight in what a neurologist says than a pharmacist based on the amount of education and training a neurologist has in his speciality. However, if you're not sure of what the neurologist is telling you, I'd absolutely go to another neurologist for a second opinion, or a third opinion, or maybe even seek out a headache specialist.
I agree with others, too, that it might be worth trying some other approaches. I don't know how often your DS gets migraines, but I have had migraines since I was 6 and my DS12 gets them a few times a month. There are a few things we use that are non-medication, although certainly we still need medication (usually Tylenol or Motrin, taken as early on in the headache as possible). We swear by moist heat, specifically in the form of a "Bed Buddy", which is a sock-like heating pad that you heat up in the microwave. I find that it works best to put it on my eyes and the bridge of my nose, although sometimes it feels best on my neck. Other people, though, like cold better than heat, and the Bed Buddy can be used for that also. (You can find the BB at Walgreens and it's pretty cheap.). Another thing that works for me is to put pressure on the bridge of my nose, usually by laying my arm across it while I shield my eyes from light. I have heard that pinching the fleshy area between your thumb and forefinger works for the sometimes-accompanying nausea. We also have found moderate success with a peppermint oil product that we found at Bath and Body Works specifically made for headaches. I rub that on my temples and my neck and my sinuses and that offers a little relief. Caffeine can be beneficial as well, so I'll often drink a coke or other caffeinated drink as soon as I feel a migraine coming on. Excedrin is supposed to be a good over-the-counter med for migraines precisely because it does have caffeine in it. And, while I'm sure you've heard this advice, the best thing is to lie still in a completely dark room and sleep it off, if possible. Usually, I try to hit the migraine with as many of these things as possible all at once.
And, too, avoid the common triggers of citrus, wine, chocoate, and cheese. Make sure that his sleep cycle is very regular regardless of how many hours of sleep he gets. If possible, keep him inside on very humid days, since the humidity itself can be a trigger, as well as the general heat. Make sure he is not getting dehydrated during the day. And sometimes vigorous exercise can be a trigger so you might want to look into that as well.
I wish you well in figuring this out.
