Tuesday, July 3, 2012

Antibiotics

The standard way to combat a bacterial infection is with antibiotics, a class of chemicals that kills bacteria. Although we group them into a single category, different antibiotics work in different ways. Some destroy the bacteria’s cell walls, causing them to burst and die. Others disrupt the processes bacterial colonies use to reproduce. Either way, the basic principle is the same—antibiotic drugs interfere with the machinery of bacterial life without affecting the way human cells operate.

Just as antibiotics have no effect on human cells, they also leave viruses, parasites, and fungal infections untouched. You’ll need different types of drugs to battle these attackers—antibiotics will have no effect. And in the case of viruses, you’ll usually be forced to wait and suffer until your immune system ramps up its defenses. (That’s why a trip to the doctor’s office won’t help you cure the average cold or flu.)

Some antibiotics work against certain families of bacteria and are called narrow-spectrum antibiotics. Others destroy wide swaths of bacterial life and are called broad-spectrum antibiotics. But neither sort can distinguish between the bacteria that harm your body and those you’d like to keep. When antibiotics wipe out the beneficial bacteria in your colon and on your skin, they often lead to side effects like diarrhea and fungal infections of the mouth, digestive tract, and vagina.

A more serious problem is antibiotic resistance—the ability of bacteria to evolve immunity to commonly prescribed antibiotics. Antibiotic resistance usually occurs when a colony of bacteria meets up with antibiotic drugs. Although these antibiotics destroy virtually all the bacteria—and they do it quickly—they may leave behind a few rare mutants that have some level of natural immunity. If the antibiotic attack keeps up, these mutants will eventually die along with their weaker relatives. But if the onslaught ends, these mutants will have a chance to establish a new, more resistant colony. Repeat the process a few times, and you’ll gradually breed stronger and more resistant bacteria. And throw in a few different types of antibiotics, and you just might produce a superbug that’s impervious to all forms of standard treatment. Even worse, bacteria have a naughty habit of swapping DNA, which means the antibiotic resistance that develops in one species can leap to another, more virulent strain.

Now that you understand antibiotic resistance, you know why your pharmacist always tells you to finish the full course of your antibiotic prescription. If you have an infection, most antibiotics will destroy the large majority of bacteria in just a couple of days. But if you stop at that point, you may spare a few, resilient stragglers. And like the son who avenges the father in a cult karate movie, those bacterial stragglers just might come back to wreak some serious havoc in your body or someone else’s.

Another way to help prevent antibiotic resistance is to avoid using products that contain unnecessary antibacterial chemicals. The best example is antibacterial soap, a mostly useless product that’s debunked.

Source of Information : Oreilly - Your Body Missing Manual

No comments: