Cold turkey... I didn't like it anyway, I think it was giving me too much gas (it's one of the side effects of it). Its my second day off Miralax and on Magnesium sulfide... and I had a normal BM. I think it's the Magnesium Sulfide that's helping. I am also sleeping better -- for almost the whole night, which is impressive for someone who dreams the weird stuff I dream about...
However, the big thing with my IBS, I think, is my period. It's due in a week so we'll see what happens then. When that time of the month comes (judging from the last two months experience, I didn't know I had IBS before), neither Miralax nor anything helps, even if I am not C, I am in so much pain that I would literally fall convulsive on the floor a couple of times a day...
My doctor told me that most people who take Miralax need a full dose (after I expressed the hope I would not need a full dose all my life). Thus I don't think any half, fourth or 6th doses would do, I myself have tried halves and 3/4s and it doesn't work... (I tried a 5/6th once, and it did work, but I think 5/6 is too close to 1 )
Jordy are you taking Natural Calm? How much magnesium does it equate to? Did you increase your dose?