Posted by Astounder on November 15, 2007, at 23:21:08
In reply to Marplan and lightheadedness, posted by brooke484 on November 12, 2007, at 10:11:04
> I've been doing fine on 30 mgs as far as side effects go, but I haven't really noticed any benefit yet. So on Sat my doctor told me to go up to 40 mgs. Well, since then I'm so dizzy and lightheaded. Now I did have this on Nardil and it usually went away after about a week of increasing the dose, so I can only hope it goes away this time too.
>
> My question is, do you think spacing out the dose would help? Like take 10 mgs 4 times a day instead of taking 20 mgs 2 times? I can handle a lot of side effects, but feeling like I'm going to pass out at any minute is not pleasant.
>
> I'll probably call my doctor in a few days, but I always like to hear your opinions too.
>
> Thanks so much.
>
> BrookeMarplan like Parnate and Nardil is an unselective, irreversible inhibitor of MAO. Irreversible meaning it forms a covalent bond with enzyme, permenantly inactivating it. You have to wait weeks for your body to produce another enzyme. Since the orthostatic/postural issue is a direct effect of inhibiting MAO, you can't fix this by spacing the dose. The hypotension is mediated by increased uptake of octopamine, a trace amine like tyramine, into noradrenergic terminals. Normally this transmitter is kept at low levels, but if you start inhibiting MAO, the levels go up.
What you could try doing is adding on a selective NRI, like desipramine. Not only will this increase noradrenaline levels, it'll prevent octopamine from entering the NA terminals. This also abolishes the pressor response to tyramine, so you can be less picky about what you eat.
poster:Astounder
thread:794573
URL: http://www.dr-bob.org/babble/20071115/msgs/795393.html