I Am 5'6 70kg 41 Years Old And Just Recently

I am 5'6 70kg 41 years old and just recently restarted taking the pill. I am wondering about how bad a loose bowel movement would have to be (as in lots of diarrhea or frequent?) for the pill not to absorb as I am going on an overseas trip and have experienced traveller's diarrhea in the past. I want to ensure the pill is effective or know for sure to use other contraception also. Thank you.