I went on a cruise around six weeks in. One night I got seasick and threw up, and I doubt it would've hit that hard without the sema, just something to think about. Otherwise by then you'll know the side effects well enough to tell if the meds bother you. Skipping a week is totally fine if you'd rather dodge the nausea or skip the trouble of hauling a fridge med around. Also remember you're on sema to fix the overindulging. The feeling that sema robs me of food is something I've had to work through. Food is still fun for me, only in smaller amounts, and at a buffet you can sample a bit of everything!