Amoxicillin is the first-line medicine for a tooth infection, typically prescribed at 500 mg three times a day for three to seven days. But antibiotics alone don’t cure most dental infections. The underlying cause, usually a dead or dying tooth nerve or a deep cavity, needs dental treatment to fully resolve the problem. In the meantime, a combination of the right antibiotic and over-the-counter pain relievers can control the infection and keep you comfortable.
First-Line Antibiotics for Tooth Infections
The American Dental Association recommends two first-line options for adults with a dental abscess: amoxicillin (500 mg, three times daily) or penicillin V potassium (500 mg, four times daily). Both are taken for three to seven days depending on the severity of the infection.
Amoxicillin is generally preferred over penicillin V because it works against a broader range of bacteria commonly found in dental infections and causes fewer stomach-related side effects. Your dentist will determine which one to prescribe and how long you need to take it. Finishing the full course matters, even if the pain and swelling start to improve after a day or two.
If You’re Allergic to Penicillin
Both amoxicillin and penicillin V belong to the penicillin family, so if you’re allergic to one, you’re typically allergic to both. Alternatives include cephalexin, azithromycin, or doxycycline, depending on the type and severity of your allergy. Cephalexin is a close relative of penicillin, so it’s only appropriate if your allergy is mild (like a rash) rather than severe (like throat swelling or anaphylaxis). Azithromycin is a common choice for people with a true penicillin allergy and is usually taken for five days rather than seven.
Clindamycin was once a go-to alternative, but many dental guidelines now recommend against it. Even a single dose carries a meaningful risk of causing a serious intestinal infection called C. difficile-associated diarrhea, which can be difficult to treat on its own.
When Dentists Add a Second Antibiotic
For more serious infections that have spread into the surrounding tissue or jaw spaces, dentists or oral surgeons sometimes combine amoxicillin with metronidazole. Metronidazole is especially effective against anaerobic bacteria, the type that thrives in the low-oxygen environment deep inside an abscess. This combination is a widely accepted approach for infections of the spaces around the teeth and jaw.
That said, once an abscess has been properly drained, anaerobic bacteria lose their foothold. Research published in the British Journal of Oral and Maxillofacial Surgery found that in otherwise healthy patients, metronidazole may not be necessary after drainage has been established. Your dentist or surgeon will decide based on how the infection looks clinically and whether lab markers suggest it’s still spreading.
Pain Relief That Actually Works
The pain from a tooth infection can be intense, and the best over-the-counter approach is a combination of ibuprofen and acetaminophen taken together. A large review covering data from over 58,000 patients found that 400 mg of ibuprofen combined with 1,000 mg of acetaminophen was more effective at reducing dental pain than any opioid-containing regimen, with fewer side effects.
For moderate to severe pain, the ADA recommends starting with ibuprofen (400 to 600 mg) plus acetaminophen (500 mg) every six hours on a fixed schedule for the first 24 hours. After that, you can switch to taking the same combination as needed. The two drugs work through different pathways, which is why combining them outperforms either one alone. An FDA-approved over-the-counter product containing both (250 mg ibuprofen and 500 mg acetaminophen per two-caplet dose) is now available.
Avoid placing aspirin directly on the gum near the infected tooth. This is a common home remedy that actually burns the tissue and makes things worse.
Why Antibiotics Alone Won’t Fix It
Antibiotics control the bacteria and reduce swelling, but they can’t reach the dead tissue inside a tooth or drain a pocket of pus. That’s why dental infections often come back if you take antibiotics without getting the tooth treated. The definitive fix is either a root canal, which removes the infected nerve and seals the tooth, or an extraction if the tooth is too damaged to save. If your dentist drains an abscess, the relief is often immediate because releasing that trapped pressure is what eliminates most of the pain.
Dentists sometimes prescribe antibiotics as a bridge, buying time when definitive treatment isn’t immediately available. If you’re given a prescription but can’t get into the chair right away, take the full course and schedule treatment as soon as possible.
Signs the Infection Is Spreading
Most tooth infections stay localized and respond well to treatment, but some can become dangerous. Go to an emergency room if you develop a fever along with facial swelling, especially if the swelling is spreading toward your eye, under your jaw, or down your neck. Difficulty breathing, trouble swallowing, or an inability to fully open your mouth are signs the infection may be moving into deeper spaces in your head and neck. These situations require IV antibiotics and sometimes surgical drainage, and they can escalate quickly.