why an antibiotic drug stops working

As we know, antibiotic drugs are medicines which are uesd to treat infections. Some antibiotics kill pathogens(disease causing germs), some antibiotics stop the growth of pathogens. different antibiotics have different mechanism of actions, some act on genetic material of pathogens, some destroy their protective barriers, while some stops their protein synthesis etc.

As you might have experienced that antibiotics used a decade back are not in use now. Have you ever considered that if an antibiotic drug is working well against an infection why do we replace it with other medicines.

All living organisms are continuously evolving, and same is the case with pathogens. Germs have developed various mechanisms to doudge antibiotics.

• Some germs manage to avoid drug absorption, hence they may survive against an antibiotic drug
• Some pathogens develop new metabolic pathways to metabolize a drug
• some germs modify their metabolism in order to bypass a drug

One of the most important reason of developing resistance is incomplete antibiotic therapy, consider a person is got infected by a pathogen A, usually there are a variety of every pathogen i.e some very weak, some average, some stronge and some very stronge.

Now just consider an infected person takes first dose of antibiotic drug, it will kill majority of germs as most of the germs are usually weaker, then the patient takes second dose, it kills pathogens with average resistance.

After the some initial doses, the condition of patient is much better and he thinks, now i am fine, why should i take further medicine.

Remember the germs left behind belongs to stronge and very stronge type. When most of germs are eleminated, a competition among germs is minimized and conditions for remaining germs are improved to grow.

A reinfection would occur, in which all the germs would be stronge type, upon them initial doses would not affect, hence now the stronger germs have gotten the chance to evolve further, this is very important way, by which antibiotics are getting in effective day by day…..