Dulcolax Adult 5mg gastro-resistant tablets work overnight in 6-12 hours with your body to effectively relieve you from occasional constipation. If you take it at night, you should be able to go to the toilet in the morning, in the comfort of your own home. Dulcolax Adult works with your body by stimulating the bowel muscle to promote a bowel movement. These laxative tablets have a gastro-resistant coating, so it works where needed, the tablets are small in size so easy to swallow and easy to take on the go when travelling.