Yes, taking antibiotics in excess may lower immunity.
Antibiotics do not kill only the bacteria that are causing an infection, but also those that naturally inhabit the body and help protect the body against invading microorganisms.
There are many bacteria which live in our digestive tract, respiratory tract and skin without causing illness. These germs play an important role in balancing various body functions, such as digestion, for example.
When these "good" bacteria die, the path is free for the "bad" bacteria to proliferate because there is no longer any competition between them.
This disequilibrium in the bacterial flora leaves most vulnerable body defenses. That is why taking too many antibiotics can lower immunity.
It is important to remember that the use of antibiotics does not weaken the immune system in itself, but it destroys the bacteria barrier with which the immune system counts to defend the organism against invading microorganisms.
See here the side effects of antibiotics.
In addition, abusive or unnecessary use of antibiotics may bacteria stay resistant to the drug, which may make it difficult to treat even common infections in the future.
Hence the importance of not taking antibiotics unnecessarily or without a prescription.
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