When you’re feeling lousy, you want a quick fix for whatever’s ailing you.

But despite what you may think, the best way to feel better may not be through antibiotics. These meds fight bacteria, so if those nasty bugs aren’t what’s making you sick, taking antibiotics won’t actually do a damn thing. Or nothing good, anyway. “You’re putting a chemical in your body that you don’t need,” says Jeffrey Linder, M.D., M.P.H, an associate professor of medicine at Harvard Medical School. “And there is zero chance it’s going to help you and a very real chance it can hurt.”

That’s because unnecessary antibiotics can cause a host of unpleasant side effects, ranging from mild conditions like rashes or the runs, to serious problems like allergic reactions or an intestinal condition called Clostridium difficile.

And what’s more, they might also be promoting the growth of antibiotic-resistant bacteria that can cause problem when you need to fight real bacterial infections down the road. In fact, a new study from the U.K. found that 13 percent of antibiotics prescribed for upper respiratory infections fail to treat the illness, possibly because the bugs were resistant.

So before you pop that penicillin, make sure you actually need it. Keep reading for 5 common ailments that don’t require antibiotics.

Sore Throat

When swallowing burns, you probably have strep throat on your mind.

But that bacterial cause is actually quite rare in adults, accounting for only about 10 percent of sore throats. So it doesn’t make sense that 60 percent of people who see their doc are prescribed antibiotics for it, as a recent Harvard study found.

Bacterial strep throat often presents with just a sore throat, fever, and swollen glands in your neck, though it might also be accompanied by pus-covered tonsils, too. Sore throats caused by viral infection—which make up the vast majority—on the other hand, have a little bit of everything: runny nose, cough, and maybe a little muscle pain.

And that’s the crux of the issue: Bacteria are single-celled microorganisms that can be killed by antibiotics. Antibiotics, on the other hand, aren’t effective against viruses. Treating a viral infection with those meds won’t help you get better.

If your symptoms point to the bacterial route, you can ask your doctor about getting a rapid strep test, says Dr. Linder. In some cases, a physician can diagnose strep based on symptoms alone. More often, though, the test is necessary for certainty.

Old-school treatments work best for strep: Penicillin remains the antibiotic of choice. Newer options like azithromycin—known by the catchy nickname “Z-paks”—may not be as effective.

“Z-paks are killing a broader spectrum of bacteria, so it kills more of the good bacteria as well as the bugs that cause strep throat,” says Dr. Linder.

Treat a viral sore throat like you would a cold: lots of rest, fluids, and some ibuprofen for the pain. People usually recover from the viruses that cause sore throat in about five or six days, a U.K. study found. In the meantime, limit your exposure to others so you won’t get them sick, too.

Acute Bronchitis

A nasty, hacking cough might not be reason for antibiotics—even if you’re spitting up plenty of colorful mucus, which is often the cause with acute bronchitis.

“When people cough up something green or yellow, they tend to freak out, but that’s your body cleaning up the viral infection,” says Dr. Linder.

“Viral infection” means antibiotics won’t help. The prescription rate should be zero, but a separate study found that people with acute bronchitis were given antibiotics 71 percent of the time.

That may be because doctors are afraid of missing a case of pneumonia, which carries some similarities with bronchitis but can be bacterial. Both can involve lots of coughing, but bronchitis will often come with a slight sore throat or runny nose, too. Pneumonia, on the other hand, often has a higher fever, shortness of breath, and chest pain in addition to the coughing.

Though your cough can linger for up to three weeks with bronchitis, you should start feeling better after Days 4 or 5. If you still feel lousy, you should make an appointment with your doctor. He or she will listen to your lungs to make sure everything sounds okay. If things sound abnormal—or if you have a fever or high pulse rate—your doctor will probably order a chest X-ray. This can diagnose pneumonia.

If your X-ray shows pneumonia, antibiotics are the recommended treatment. But if it’s just bronchitis, keep yourself comfortable with lots of rest, fluids, and a cough suppressant, especially at night, says Dr. Linder.

Skin Abscess

Think a spider bit you? It could actually be a skin abscess, a painful, pus-filled infection on your skin.

These tend to look like a pimple, boil, or pustule that develops and grows. And they hurt, too, which is why many patients actually think they have a spider bite, says Timothy Jenkins, M.D., an assistant professor in the division of infectious diseases at the University of Colorado School of Medicine.

These infections are caused by bacteria—most commonly by staph, including MRSA in some cases—but they don’t necessarily need antibiotics.

In fact, a study by Dr. Jenkins found that almost half of the abscesses in the study could be treated by drainage alone. Yet doctors prescribed antibiotics in nearly 75 percent of these

“For most small abscesses or simple abscesses, simply opening up the cavity so the pus infection can drain out is adequate,” he says.

Fair warning: the drainage can be painful, which is why some patients might be clamoring for pills instead. The doctor makes a small incision into the abscess and uses an instrument to break up any pockets of pus inside. Then they pack the abscess with gauze to keep it open so the infection continues to drain out.

That’s enough to treat most simple abscesses, but for more complex cases, you may also need antibiotics. These include if you have a compromised immune system due to a condition, or if your abscess continues to expand or causes the surrounding skin to become red or swollen, says Dr. Jenkins.

Sinus Infection

Each year, one in seven adults experience the stuffy nose and pounding facial pain that signal nasal passage inflammation, or a sinus infection.

In most cases, the bug is due to a virus, not bacteria. However, 83 percent of sufferers are prescribed antibiotics.

If you have a run-of-the-mill sinus infection, you can treat it at home. Try ibuprofen or acetaminophen to reduce fever and pain, a decongestant like Sudafed 12-Hour, and a nighttime cold remedy like Nyquil to help you sleep, says Dr. Linder. You can also use a nasal spray for up to five days.

“It’s much more important to get the little openings of the sinuses open with decongestants than it is to do anything with antibiotics,” he says. “Most people will get better with that.”

There are three situations where antibiotics might be indicated, says Dr. Linder. These include severe symptoms—high fever and profound sinus pain—right from the beginning, symptoms that persist for 10 days or longer, or symptoms that continue to worsen.

In these cases, you should make an appointment with your doctor. If an antibiotic is indicated, your doc will likely prescribe Augmentin, a combination of amoxicillin and clavulanic acid, which allows the antibiotic to work more effectively.

 Toothache

When your tooth is throbbing, you want relief—and fast. But in many cases involving a simple toothache, antibiotics won’t help at all.

You might have dental sensitivity, where you feel pain when drinking something hot or cold because your tooth’s root is exposed. Or a nerve in the middle of the tooth can be become inflamed, either from clenching or grinding your teeth or because of a cavity.

Bacteria doesn’t cause this inflammation, so antibiotics won’t provide any relief, says Thomas Sollecito, D.M.D., chairman of the department of oral medicine at the Penn School of Dental Medicine.

Back in 2001, a study in the British Dental Journal found that 74 percent of people with a toothache who visited an emergency dental care clinic were prescribed an antibiotic. That’s a problem, since the researchers said that local treatment could have relieved the pain.

 

This would include things like filling the cavity or sealing an exposed root, says Dr. Sollecito.

 

There are some cases in which your toothache will require an antibiotic. They are: when the area around your tooth is swollen; when you have pockets of pus; or you develop fever, chills, or malaise.