I weed myself a bit when being sick in the late first/early second trimester - someone had posted on this thread about it the day before so it was less of a shock!
I found that taking my tablets first thing in the morning (even after eating) started to give me heartburn when I was pregnant when it had been no problem for years, so I switched my schedule around (sertraline after lunch, vitamins after dinner, aspirin before bed).
Edit: sorry just realised you were probably asking about anti sickness tablets and not tablets in general!