Hi Eric
With Ditropan, the temdency will most certainly be towards constipation : with any pharmaceuticals, you can find that they will state a lot of side-effects as being possible, basically because they are obliged to do so by law.
When they trial drugs, people trialling the drug report all symptoms, many of which are in fact unrelated to the drug at all, but coincidentally the person is experiencing whilst trialling the drug. If enough, and enough might represent a relatively small proportion of the number of people trialled, then they have to put it as a possible side-effect in their prescribing literature. I know all of this having worked within the pharmaceutical industry as a Medical Representative - it's just something they are obliged to do if enough of the 'trialled' people report symptoms, even if the number might only represent a few percent of the overall number in the trial. Nausea & Vomiting is one you'll see on almost all medications - and under the 'special precautions' listing in the prescribing information for any drug, you'll find 'use with caution with any liver damage or dysfunction' - which is the 'big' one - since it's the one that avoids huge lawsuits - all drugs, well almost all drugs, have to make a pass through the liver - its a good and a bad thing, since the liver detoxifies any 'poisons' we ingest - the bad side, in so far as drug manufacturers are concerned, is that this 'pass' through the liver renders a lot of the active ingredient in the drug useless. Anyone with liver impairment that is severe enough will allow more drug to get through to the rest of the body - and in certain cases, the amount it lets through can be lethal or damaging at least - apologies for the ramble-on there - I don't know what came over me!!

As an anticholinergic, physiologically, Ditropan will most definitely reduce the bowel's natural peristaltic rhythmic movement more make the bowel generally significantly more sluggish - and should thus be helpful with IBS rather than aggravate it. It happens to a lesser or greater extent between individuals - I would have imagined for yourself, for example, that since you have severe side-effects with dry mouth, that you would also have very significant ones with the gut as well - but again, there are so many variables with this - things don't always behave as we expect them to. Some people report a degree of bloating of the abdomen - I myself do get just a little of this, which is entirely related to the aforementioned slowing down of the gut in general.
Now then.....what to do......
I would really not advise that you take more at a time, Eric - but that if at all possible, to actually take less at a time. The dry mouth you are experiencing, which is very significant indeed for you, is an indication that the drug is very active within you - it will never stop all sweating - well, that's not strictly speaking true, as it can do if enough is taken but to the detriment of the individual - we do need to sweat, even if just a little and not doing so at all is a very harmful thing - but I digress.
Taking more at a time, for you, will merely worsen the dry mouth - and lets remember it's already unbearable and requires that you need Nystatin - in other words, you are highly unlikely to reduce your 'sweating' further, or if so by a very small amount - but your side effects will worsen, something I really don't feel you could tolerate and, more importantly, it wouldn't be the right treatment regime for you.
With me, I am able, at times, to take a large-ish dose because it doesn't cause me anything like the grief it causes you, Eric - purely due to us having different anatomical & physiological qualities to one another.
Here's what to do:
Begin by slightly reducing the amount you normally take : if you normally take one tablet, try taking 3/4 of a tablet and if that still works as well, pretty much, as a whole tablet, so much the better.
Then try reducing it to a half tablet - in other words, find a dosage regimen that suits you, with the balance of relieving some of your HH symptoms but not causing you so many side effects as to render it troublesome to bother going through it all the time.
There will come a point where the efficacy will reduce below that which you are gaining any benefit from, but you will almost certainly find that by reducing the dose, even by a small amount, 'should' reduce the side-effects, most notably, the mouth dryness.
It's a difficult concept to get your head around sometimes, I do realise - it's the side-effects that tell a physician/clinician that a drug is doing what it's designed to do, not simply how well it's treating the thing it's been prescribed for. For you to increase the dose would not be the way to go - it's hard to imagine that the drug could become more 'active' within your body, Eric - it's causing you to need Nystan, and that's a severely dry mouth. It may be, as it is the case with most people, that the best you can hope for with an anticholinergic of any kind is partial relief from the sweating. A lot of people write to me and say that they are still sweating, it hasn't worked etc etc - their symptoms have reduced markedly but their expectations of the drug, was that it would take away ALL issues of sweating - which it just isn't designed to do and, in fact, is a very dangerous goal to aim for, especially in some climates and some occupations, lifestyles etc.
Also, as you mention, don't take more until at least 4-5 hours have elapsed - this is very important if what we're aiming for is the same or very close to the same HH relief but a much improved side-effect profile for you. Something else to note, though I'm sure you're a little aware of anyway, is to take it around one hour or so before you'll 'need' it.
I would strongly advise to reduce it - ie each dose you take - by just a quarter of a tablet per dosage, to begin with - and maintain this for a week at least, noting down what has happened, is the sweating relief less or around the same, any improvements in the mouth etc etc - and of course, keep me posted

I wish you well with it all, Eric - and feel sure that there is at least some improvement ahead for the mouth dryness, however slight, without it compromising the HH relief significantly.
Cheers for now - let me know anytime if you need more help/advice with this or anything else - I'm glad to be able to help

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