How long should you space out giving probiotics with metronidazole? I’ve read if you give too close it can make the probiotics not work, but not sure how close is too close. Has anyone given metronidazole for a long period or given then taken a break and given again when things got worse? We are giving it to our boy who has stomach cancer and it does seem to help firm things up (which is great considering he can’t control when/where he goes so I’m cleaning spots from my house pretty much daily).