Dulcolax pico perles are apparently good and gentle so no tummy cramps like you get with some other laxatives.
You take between 2-4 and they work within 6-12 hours.
I've ordered some from amazon for just in case.
you can have senna or dulcolax , BUT I find them really harsh and give me terrible cramps ( work though !!!) as BB said dulco pico perles are great and my local tesco sells them , they work quickly and are gentle movicol is also great stuff and gentle too xx