By Jon Johnson

Reviewed by Dena Westphalen, PharmD

A tooth infection, or an abscessed tooth, generally occurs as a result of tooth decay and poor oral hygiene. 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. Without treatment, the infection may spread to other areas of the jaw or even the brain.

Dental decay and cavities are very common. As one article notes, up to 91% of adults ages 20–64 have cavities. Also, around 27% of people in the same age group have untreated tooth decay. Treating tooth decay early is important to prevent complications such as tooth infections.

Anyone who experiences a tooth infection should see a dentist right away to prevent the infection from spreading.

One of the first things a dentist will likely recommend is an antibiotic to kill the infection. Some antibiotics work better than others for tooth infections, and there may also be some over-the-counter (OTC) pain medications to help with the symptoms.

When to use antibiotics for a tooth infection

Dentists will typically only recommend antibiotics in dentistry for toothinfections. However, not all infected teeth require antibiotics.

In some cases, a dentist may simply be able to drain the infected area, remove the infected tooth, or perform a root canal to fix the issue.

They tend to avoid recommending antibiotic sunless they are absolutely necessary, such as when the infection is severe or spreading, or if a person has a weakened immune system.

List of types and dosages

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

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.

As a study in the Dentistry Journal notes, there are over 150 different strains of bacteria that occur in the mouth. Many of these bacteria have the potential to grow and cause an infection.

Treatment may change depending on the bacteria causing the infection, though much of the time, dentists simply recommend an antibiotic that works against many types.

Penicillin class

Penicillin-type drugs are common forms of antibiotics for tooth infections. This includes penicillin and amoxicillin. Some dentists may also recommend amoxicillin with clavulanic acid, as the combination may help eliminate more stubborn bacteria.

Typical dosages of amoxicillin for a tooth infection are either 500 milligrams (mg) every 8 hours or 1,000 mg every 12 hours.

Typical dosages of amoxicillin with clavulanic acid are around 500–2,000 mg every 8 hours or 2,000 mg every 12 hours, depending on the minimum effective dosage.

However, some bacteria may resist these drugs, making them less effective. In fact, many doctors now choose other antibiotics as their first line of treatment.

Also, some people are allergic to these drugs. Anyone who has had an allergic reaction to similar medications should tell their dentist before receiving their treatment recommendation.

Clindamycin

Clindamycin is effective against a wide range of infectious bacteria. As a study in the International Dental Journal notes, some researchers recommend clindamycin as the drug of choice to treat dental infections, as bacteria may be less likely to resist this drug than penicillin-class drugs.

A typical dosage of clindamycin is either 300 mg or 600 mg every 8 hours, depending on which dosage will be effective.

Azithromycin

Azithromycin works against a wide variety of bacteria, working to halt their growth. It may be effective in treating some tooth infections, though 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.

The typical dosage of azithromycin is 500 mg every 24 hours for 3 consecutive days.

Metronidazole

Metronidazole is an antibiotic that doctors and dentists use to treat a number of infections. However, it may not be suitable for everyone and is typically not the first choice of treatment.

The dosage for metronidazole is around 500–750 mg every 8 hours.

How long do they take to work?

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.

It is important for people to complete a full round of antibiotics, taking all of the prescribed medication exactly how the dentist says to take it. Although a person may begin to notice their symptoms go away after a couple of doses, completing the full round of antibiotics helps prevent the infection from coming back or getting stronger.

As the International Dental Journal study notes, the majority of acute infections resolve in 3–7 days.

Side effects

Although antibiotics can help clear up an infection to prepare a person for dental work, these drugs do have some possible side effects.

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

Other tooth infection treatments

Antibiotics may help clear the active infection, but the tooth will 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. In reality, most tooth infections require work on the actual tooth itself to clear up completely.

Natural remedies to ease symptoms

Some OTC remedies may also help people control the symptoms of their infection. This includes OTC pain relievers such as ibuprofen (Advil) and acetaminophen (Tylenol).

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

• gently rinsing the mouth with warm salt water
• 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 each day and seeing a dentist for regular checkups, may help prevent tooth infections and their complications.

Summary

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 helpful home remedies may help keep swelling down or ease pain while taking antibiotics and preparing for the dental procedure.