Colin,
This is a very interesting topic... There used to be two schools of thought on when to start probiotics if you're being treated with an anitbiotic.
The first argues why waste the probiotic while still taking an antibiotic. If the antibiotic and probiotic are in the GI tract at the same time, there's a high probability the anitbiotic will wipe out the probiotic as fast as it's taken. There is also a reasonable logic that the probiotics will consume a portion of the antibiotic lessening its effectiveness in stopping the bacterial infection elsewhere in the body.
The other school of thought is keep replacing and recolonizing the friendly bacteria in the GI tract with probiotics taken daily while taking the antibiotic... Some of these friendly bacteria might just survive. Moreover, the probiotic will help calm down the gut and help prevent diarrhea.
Well... the following is the best answer I can find... I was wrong and stand corrected suggesting to wait until the 10-day course of antibiotic was completed...
I just spent the better part of two hours going over several articles and published results from clinical trials on this very topic... The consensus is take probiotics daily along with the antibiotic. Separating the two by 12 hours is likely a good idea as is taking the right kind of probiotic as you'll see in the following.
"Most of these trials used different strains of Lactobacilli, Bifidobacteria, or Saccharomyces boulardii. Lactobacillus and Bifidobacterium are two of the most common genera used as probiotics, so these supplements are readily available in most health food stores or vitamin shops. S. boulardii is actually a beneficial yeast rather than a bacteria, so it’s particularly useful during antibiotic treatment because the antibiotics can’t kill it."
"S. boulardii is also preferable under these circumstances because there’s no risk of it harboring genes for antibiotic resistance and later transferring those genes to pathogenic bacteria."
A couple of the easy to read articles on probiotics are at the following links:
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Nearly all the articles suggested fresh fermented veggies like kimchi and unsweetened live yogurt... Add your own fresh fruit.
So along come the prebiotics... essentially food for the friendly bacteria...
"However, you can’t expect manufactured probiotic and prebiotic supplements to achieve the diversity of an ancestral microbiome on their own."
As always... remember to discuss prebiotics and probiotics with the physician who prescribes the antibiotic...
Take care.
V/R, Batch