I've played with the doses a bit.
I was prescribed 4 grams a day (eight 500 mg pills: two pills, four times a day), and I've gone up to 5 grams a day, but that didn't help any more than 4 grams. I've down to 2 grams a day, but the joint pain started creeping back. I'm now on 3 grams a day (three pills, twice a day) which seems to be a happy medium, although I'm a bit stiffer than usual. I'd probably re-up to 4 grams if I could remember to take the darn things in the middle of the day.
Part of my memory wants to say the GI told me 6 grams a day is the absolute max -- and only for a limited time.
The side effects do increase with increased dosage.