Do you need antibiotics for a toothache? What they can and can't do

What’s probably going on

When a tooth aches, the trouble is usually inside it or at its root.

• An inflamed nerve. A deep cavity or crack can irritate the soft center of the tooth (the pulp). The pain can linger after cold, or throb on its own. See throbbing tooth pain.
• Irritation at the root tip. The tooth hurts to bite on or tap. See tooth hurts when biting.
• An abscess. A pocket of infection at the root or in the gum. It often throbs and can bring a bad taste or a bump on the gum. See tooth abscess.

An inflamed nerve usually isn’t an infection at all, so there’s nothing for an antibiotic to treat. When the nerve has died or an abscess has formed, the fix is to clean out or remove the source.

That’s why the American Dental Association’s 2019 guideline on dental pain and swelling recommends against antibiotics for most of these problems. It was written for adults with a normally working immune system. It puts dental treatment first: a root canal (or the first step of one), or draining the infection.

The guideline found antibiotics likely give little or no benefit for these problems and can cause real harm. When the dentist can treat the tooth at the same visit, it advises against adding antibiotics, even for an abscess that stays in one spot.

When antibiotics do make sense

The picture changes when an infection starts to spread beyond the tooth. The ADA guideline says dentists should prescribe antibiotics when there are signs the whole body is involved, such as a fever or feeling generally unwell. ADA MouthHealthy puts it simply: a fever can mean the infection has spread beyond where it started.

There’s one more case. If you have an abscess (pus and swelling in one spot) and the dentist can’t treat it right away, the guideline suggests antibiotics to bridge the gap, with an urgent referral for treatment. For some other infected teeth, a dentist may give a prescription to fill only if things get worse.

Either way, the antibiotic is a partner to treatment, not a replacement. The tooth still needs a root canal, drainage or extraction, as soon as possible.

If you have a weakened immune system (for example from cancer treatment, an organ transplant, HIV or medicines that suppress the immune system), tell your dentist. The guideline doesn’t apply to you, and your dentist may handle things differently.

Some signs mean the infection may be spreading fast. Those belong in an emergency room, not a pharmacy line.

• Swelling in your face, jaw or neck that is growing, or swelling near your eye
• Trouble swallowing, breathing or opening your mouth
• A fever along with facial swelling

Call 911 if you’re having trouble breathing.

What to do tonight

If you have none of those signs, these steps often make the night easier.

1. Take an over-the-counter pain reliever as the label directs. For adults and teens 12 and up, the ADA’s toothache guideline puts anti-inflammatories such as ibuprofen or naproxen first, alone or combined with acetaminophen. Ask a pharmacist first if you take other medicines, are pregnant, or have stomach, kidney or bleeding problems.
2. Hold a cold pack on your cheek. About 20 minutes at a time. It can dull pain and keep swelling down. Never use heat on a swollen face.
3. Rinse with warm salt water. About half a teaspoon of salt in a cup of warm water. Swish and spit.
4. Floss gently around the sore tooth. Food wedged against the gum can ache like a bad tooth.
5. Sleep with your head raised. An extra pillow can ease the pressure that builds when you lie flat. See how to sleep with a toothache.
6. Book a dentist for the first opening. If you can’t reach your own dentist, a video visit after hours can help you decide how urgent it is.

For the full list, see what to do for a toothache right now.

What not to do

• Don’t take leftover antibiotics. Only a dentist or doctor should decide whether you need them. The CDC warns that saving antibiotics for later can delay the right treatment.
• Don’t take someone else’s antibiotics. The CDC says this can delay the best treatment for you, make you sicker or cause side effects.
• Don’t ask for antibiotics to put off treatment. They don’t fix the tooth, and treatment still can’t wait.
• Don’t put aspirin on the tooth or gum. It burns the tissue.

Why doctors are careful with antibiotics

Antibiotics are useful drugs, but they aren’t harmless. ADA MouthHealthy lists yeast infections, nausea, vomiting and diarrhea as common side effects. The CDC adds rashes, dizziness, severe allergic reactions and C. difficile, a gut infection that can damage the colon.

Any time antibiotics are used, the CDC says, they can add to antibiotic resistance. ADA MouthHealthy notes that overuse breeds bacteria the drugs no longer work on, so they may fail when you really need them.

If you have old antibiotics at home, the CDC suggests a drug take-back program, often at a pharmacy. If there isn’t one, put the pills in a plastic bag with dirt, kitty litter or used coffee grounds and throw it in the household trash.

How a dentist fixes it, and what it costs

A dentist usually needs an exam and an X-ray to find the cause. Then the fix is one of these:

• A filling for a cavity that hasn’t reached the nerve.
• A root canal to clean out an inflamed or infected nerve, usually followed by a crown. See root canal cost.
• Draining an abscess, often as part of a root canal or an extraction.
• Taking the tooth out when it can’t be saved. See tooth extraction cost.

The price depends on the treatment, the tooth, where you live and your coverage, so ask for a written estimate before work starts. For a rough idea, try the dental cost estimator. If you don’t have insurance, a dental savings plan (a discount membership, not insurance) can lower the price at participating dentists.

How to keep it from coming back

A tooth that needs a root canal often started as a small cavity or crack.

• Brush twice a day with a fluoride toothpaste.
• Clean between your teeth once a day.
• Cut back on sipping sugary or acidic drinks through the day.
• Get regular checkups, so small problems get small fixes.

For help picking tools, see the best electric toothbrush and water flosser vs string floss.