Hello. My Partner Is On A Strict Weight Loss Program

Hello. My partner is on a strict weight loss program with a personal trainer and dietician. He is using a variety of herbal supplements, one of which is a colon cleanse. He started with diarrhea for the first week, now the last week is constipated but for the past three days has a very sore area of skin that feels like it is burning all the time. Can a 15 day herbal colon cleanse cause a yeast infection on the skin around the anal opening?