Been on an antibiotic any time in the last two years? Well, the antibiotics may still be affecting you. Even short courses of antibiotics can leave antibiotic-resistant genes in the bacteria that remain in the gut for up to two years. Previously, antibiotics were thought to have a short-term effect on gut microflora. It was thought that after a short period of wiping out the bacteria, the gut bacteria would reestablish the same levels as before the antibiotic within a few weeks.

Turns out, that’s not the case. A review published in the journal Microbiology found that antibiotic-resistant genes were at very high levels just seven days after antibiotic treatment, but those genes persisted in some cases for up to two years, even in individuals who had taken no further antibiotics. The researchers call for “rational antibiotic administration guidelines to be put in place.”

This week, renew your gut. If you suspect that antibiotics may have wreaked havoc on your gut microflora, take a high quality, high potency, multi-strain probiotic to support healthy gut balance.