A tooth infection often involves bacteria, and a dentist may prescribe antibiotics in some situations. Examples include amoxicillin, phenoxymethylpenicillin, metronidazole, and clindamycin.

A tooth infection, or an abscessed tooth, generally occurs due to tooth decay. However, it can also develop due to previous dental work or traumatic injury.

When an infection occurs, it causes a pocket of pus to form in the mouth as a result of an overgrowth of bacteria. This infection often causes swelling, pain, and sensitivity in the area.

While some over-the-counter (OTC) pain medications can help with the pain, antibiotics may be necessary to target the bacteria causing the infection.

This article outlines when antibiotics may be appropriate for a tooth infection and explains what antibiotics a doctor might prescribe.

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According to a 2023 overview of research, antibiotics are not the first-line treatment for tooth infections.

Instead of prescribing antibiotics, a dentist may be able to drain the infected area, remove the infected tooth, or perform a root canal to fix the issue.

However, dentists may prescribe antibiotics alongside other surgical treatment options if there are signs that the infection is spreading outside of the oral cavity. They may also prescribe antibiotics to those with a weakened immune system.

Due to growing antibiotic resistance, doctors tend only to recommend antibiotics if they are absolutely necessary.

More than 700 different strains of bacteria are present in the mouth. Many of these bacteria have the potential to grow and cause an infection.

Although antibiotics can help clear a tooth infection in some cases, it is important to use the appropriate antibiotic in each situation.

Treatment may change depending on the bacteria causing the infection. However, dentists may initially recommend an antibiotic that works against many types.

A dentist may initially prescribe one or more of the following:

AntibioticDose in milligrams (mg)Notes
Amoxicillin500 mg three times a day for 5 daysA dentist may double the dose for severe infections.
Phenoxymethylpenicillin500 mg four times a day for 5 daysA dentist may double the dose for severe infections.
Metronidazole400 mg three times a day for 5 daysA dentist may prescribe this if a person is allergic to penicillin.

Alternatively, they may prescribe this antibiotic alongside amoxicillin or phenoxymethylpenicillin.
Clindamycin150 mg four times a day for 5 daysDue to allergies or drug interactions, clindamycin may be the only alternative to penicillin-class antibiotics.

This antibiotic has a higher chance of causing gastrointestinal side effects, so a dentist will consider these risks when prescribing it.

If a person does not respond to the above treatment, a dentist may prescribe:

Co-amoxiclav375 mg three times a day for 5 days
Clarithromycin250 mg two times a day for 5 days

A dentist may also prescribe azithromycin. Azithromycin works against a wide variety of bacteria, halting their growth.

Dentists may only recommend it to people who are allergic to penicillin-class drugs or who do not respond to them or other drugs such as clindamycin.

According to an older article from 2014, doctors may prescribe 500 mg of azithromycin every 24 hours for 3 days.

Although antibiotics can help clear up an infection or prevent an infection from developing after dental work, these drugs have some possible side effects.

Common side effects from antibiotics include:

More serious side effects include Clostridium difficile infection, life threatening allergic reaction, and anaphylaxis.

However, these side effects can vary with each type of antibiotic. It is important to discuss any possible side effects of taking a drug with a doctor before moving forward with that particular treatment.

Learn more about the side effects of antibiotics.

How long each antibiotic takes to work varies depending on many factors, such as the severity of the infection and how effectively the drug eliminates the infectious bacteria.

People need to complete a full round of antibiotics, taking all of the prescribed medication exactly as the dentist advises.

Although a person may notice their symptoms begin to go away after a couple of doses, completing the full round of antibiotics helps prevent the infection from returning or getting stronger.

However, a 2021 systematic review says that the infection should begin to clear 2–3 days after taking antibiotics.

Antibiotics may help clear the active infection. However, the tooth may need work to keep the infection at bay. This typically means undergoing one or more procedures in the area, such as:

  • draining the abscess
  • filling in any cavities
  • performing a root canal
  • extracting the tooth

Antibiotic treatment for a tooth infection is just one part of the solution. Most tooth infections require work on the tooth itself to clear up completely.

There may be some helpful practices a person can try at home to ease symptoms, such as:

  • gently rinsing the mouth with warm saltwater
  • gently rinsing the mouth with baking soda in water
  • avoiding very hot or very cold foods to prevent sensitivity
  • chewing with the opposite side of the mouth to reduce additional injury to the area
  • brushing with a very soft toothbrush around the sensitive area
  • avoiding very sharp, hard-to-chew foods that may bump into the sensitive area or become stuck in the teeth

Adopting good oral hygiene practices, such as brushing and flossing daily and seeing a dentist for regular checkups, may help prevent tooth infections and their complications.

Tooth infections do not usually go away on its own. A person will require prompt dental treatment.

The following are common questions about antibiotics for tooth pain.

What is the best antibiotic for a tooth infection?

There is no single antibiotic that is best for treating a tooth infection. The type of antibiotic a dentist recommends will vary depending on the bacteria causing the infection.

This is because different antibiotics work in different ways to eliminate different strains of bacteria. However, doctors will often choose amoxicillin as the first-line treatment.

How long does it take for a tooth infection to go away with antibiotics?

After a person begins to take antibiotics, it can take 2–3 days for the infection to begin to clear. A person can finish the entire course of the medication as their doctor prescribes, even if they start to feel better sooner.

Will antibiotics stop tooth pain?

Typically, antibiotics for a bacterial infection show some improvement in pain within a few days.

While taking antibiotics, a person can manage pain with OTC pain relievers such as ibuprofen (Advil) and acetaminophen (Tylenol).

Can a person get antibiotics for tooth infection over the counter?

It is not possible to get OTC antibiotics for a tooth infection. A person with a tooth infection can contact a dentist for appropriate treatment.

Although antibiotics may help clear up a tooth infection, they are only one part of the solution. Most tooth infections require a dental procedure, such as a root canal or tooth extraction, to completely clear up.

Prompt treatment is important to keep the infection from spreading. Some home remedies may help keep swelling down or ease the pain while taking antibiotics and preparing for the dental procedure.