The short answer is, no. Or at least, not all of them.
In the last few decades as antibiotic-resistant superbugs have emerged in the general public, doctors' prescribing practices have come under extreme scrutiny. When Penicillin was discovered by Alexander Fleming in 1928 it was viewed as a wonder drug. Even before Fleming's discovery and the mass marketing efforts that followed, bread with blue mold was used to treat infected wounds in the Middle Ages. It provided physicians a way to treat people and defeat the bacteria that usually resulted in death.
Still today, many people trust antibiotics. They figure there can't be any harm in taking them even if scientifically antibiotics aren't actually effective in treating their particular illness or condition. People just know that antibiotics kill things that make them sick.
People are also looking for a quick fix. They don't want to have to suffer a runny nose or sore throat or the common cold, so they ask their doctor for a prescription. "Isn't there some kind of pill I can take?"
In the scrutiny after the last few superbugs, many doctors have been found to prescribe antibiotics for conditions and illnesses that do not respond to antibiotics. The vast majority of those doctors examined also understood that over-prescribing antibiotics had led to increased amounts of antibiotic-resistant strains of those illnesses that do respond to antibiotics.
How to Antibiotics work?
Antibiotics are used to treat infections caused by bacteria, fungus, and certain parasites. They do not work against illness or conditions that are caused by viruses. Colds, the flu, most coughs and sore throats are caused by viruses. Some sinus and ear infections, and certain kinds of pneumonia and strep throat are examples of illnesses that are caused by bacteria and normally respond to antibiotic treatment.
Antibiotics work by killing bacteria or preventing them from multiplying.
Viruses are smaller than bacteria and work by actually invading your body's cells and using the cells' reproductive mechanisms to spread and multiply and create more viruses. The flu, the common cold, many types of sore throats, coughs, ear infections, bronchitis, and some strains of pneumonia are examples of illnesses that can affect the respiratory tract and which are caused by viruses. Since viruses do not respond to antibiotics, neither will these illnesses respond to antibiotics.
Guidelines for Antibiotic Use
It used to be that people believe that green mucus seen in conjunction with a cold or sinus infection was a sign of an infection. That's not what doctors believe now.
Patients are often shocked when they visit a doctor after they've been sick for a couple of days to hear the doctor say, "Go home. Get some rest. Drink plenty of fluids." That's because at the early stage the infection is viral and nothing can really be done at that point but to let your body naturally work through the infection. If the condition worsens or has not improved after a period of about 10 days, then chances are it has progressed from a viral infection to a bacterial infection. That's when they can be treated with antibiotics.
Proper use of Antibiotics
Antibiotics only work if they are used against bacterial infections, and even then they must be taken properly.
Antibiotics work on the rule of the survival of the fittest. The weaker bacterial cells are killed off first while the battle continues to wage against the stronger cells. If an antibiotic regiment is stopped too soon either by the patient deciding they no longer need antibiotics because they feel better, or the prescription running out before the infection is completely gone, the strong germs can keep growing and become antibiotic resistant. This can happen if you take the same antibiotic too many times, or when germs are left behind in your body after an antibiotic regimen is stopped or is not completed.
To prevent the development and spread of antibiotic-resistant strains of bacteria, patients need to be aware of the types of illnesses and symptoms that will respond to antibiotics and not always arrive in their doctor's office with the thought that antibiotics will cure anything.
If, after examination reveals that you do have a bacterial infection that will respond to antibiotics, remember to:
1) Use the antibiotics only when your doctor prescribes them;
2) Do not share the antibiotics with anyone else;
3) Don't stop taking the medication too soon
4) Follow the instructions your doctor gave you
Sources: www.webmd.com, http://familydoctor.org, http://drugs.about.com, http://fccmg.com (Health and Wellness Tips from Family Care Centers), www.merck.com, www.wikipedia.com