The maximum daily dosage of bisacodyl in tablet form is 30 mg. (six 5 mg. tablets) per day for an adult.

https://www.sharecare.com/health/laxatives/maximum-daily-dosage-of-bisacodyl

The maximum daily dosage of bisacodyl in tablet form is 30 mg. (six 5 mg. tablets) per day for an adult. Use of bisacodyl for more than a week is not recommended unless under the supervision of a doctor. Long-term use of bisacodyl can decrease the normal functioning of the bowels.