I've been dealing with something similar over the last several weeks. Not to the same degree as your husband, certainly not 20 to 30 times a day. ...but I'd say over the last 2 months or so, 80% of my bowel movements have been in the form of diarrhea. I haven't had very many solid bowel movements. Even if I don't eat, there's a chance I'll have diarrhea. I don't eat very healthy and I've had a history of gastrointestinal issues since I was probably 8 or 9 years old... I'm almost 25 now.
I'm not sure where the problem really comes from. In addition to the history of issues, I also have anxiety issues and also developed some sort of acid reflux problem too.
Which brings me to another weird issue I've noticed since it happened for the third time about two mornings ago.
I've never really been one to get sick or throw up from being sick, at least not often. Maybe like once a year. ...but for the third time in maybe 2-3 months, I've thrown up after eating pizza. The first two times it wasn't long after. This time I was asleep and woke up with the urge to vomit, ran to the bathroom and let loose.
I know my insides are banged up pretty bad... and there's a history of colon cancer and such in the family...
I haven't been to a doctor for it in years, not too sure I intend too either. Unless it happens to get drastically worse later this year.