Antibiotics, intestinal flora and probiotics
The numerous antibiotics I take attack not only the bacteria destroying my lungs, but also the bacteria that play a positive role in my intestinal flora. Everyone seems to be saying that probiotics can restore intestinal flora. What exactly are probiotics? How effective are they?
. It is a well-known fact that systemic antibiotics (oral and intravenous) can affect normal microbial flora in the mouth, vagina and intestines. Antibiotic sprays, however, do not produce this inconvenient effect. Antibiotic therapy may affect the intestinal flora without producing any symptoms, but patients may experience abdominal pain and soft diarrhea-like stools. There may also be a worse complication: C. difficile colitis, also called pseudomembranous colitis. This complication occurs mostly in hospital environments, where patients may be colonized by this toxin-producing bacterium. The colitis can sometimes be severe and destroy the colon, requiring surgical resection or even causing death.
Are probiotics, which are made up of similar bacteria to those found in the intestinal flora, effective in preventing digestive complications?
The experience of many patients using probiotics suggests some effectiveness. However, the ultimate
medical proof of effectiveness lies in double-blind clinical trials involving a large number of patients, in
which either probiotics or a placebo (inert substance) is administered concurrently with antibiotics. The
superior performance of the probiotics over that of the placebo would prove their effectiveness.
The problem is that no studies have been conducted to date, apart from a recent research project in England. That study seems to demonstrate the relative effectiveness of a probiotic preparation composed mainly of lactobacilli. However, further studies would be required to confirm the results. Another problem lies in the very nature of probiotics, which are classified as a natural product, not a drug. There is no control over the quality of this type of product, so we cannot be certain that the probiotic contains the right number of bacteria or even the kind of bacteria it claims to contain. That is why gastroenterologists and infectious disease specialists do not systematically recommend probiotics to prevent or treat intestinal complications when administering systemic antibiotics. In addition, according to an infectious disease consultant, probiotics are contra-indicated in people who are immunodepressed (such as cystic fibrosis patients following a lung or liver transplant).