Antibiotics and teeth: when they're needed and when they're not

Updated on 18 March 2026 · by Clínica Dental Bizkaia

In short: many people think an antibiotic “cures” toothache. It doesn’t: it can slow an infection, but it doesn’t remove the cause (the cavity, the nerve or the tooth are still there). Taking it on your own masks the problem and fuels resistance. Here’s when it’s really needed and when it isn’t.

Does an antibiotic stop toothache?

Not directly. Toothache usually comes from a deep cavity, an infected nerve or a broken tooth. The antibiotic can bring an infection down, but the cause is still there: as soon as you stop, the pain returns. What really fixes it is treating the tooth (a filling, root canal or, if there’s no other option, extraction).

When is it really needed?

When the infection is spreading and the body notices: significant facial swelling, fever, feeling unwell… There the antibiotic helps control it while the tooth is treated. Also in some patients with specific health conditions. But in many cases, by treating the tooth in time, it isn’t even necessary.

Why not self-medicate?

For three reasons:

It masks the problem: it removes the warning (the pain or swelling) without fixing anything, and the tooth keeps getting worse inside.
Resistance: using antibiotics when you shouldn’t makes them work worse over time, for you and for everyone.
Dose and type: not all of them are right, nor in any amount. That’s decided by whoever examines you.

A painkiller is not an antibiotic

To cope with the pain until your appointment, an over-the-counter painkiller/anti-inflammatory helps. But relieving is not curing: ibuprofen takes the pain away for a while, not the infection. Don’t confuse them or mix them on your own.

And an abscess?

An abscess is the perfect example: sometimes an antibiotic is prescribed to bring the swelling down, but the tooth that caused it always has to be treated afterwards. If you stop at the antibiotic, it comes back.

Got a sore tooth or a swollen face? Don’t reach for the box of antibiotics at home: let a dentist see you. The first visit is free and, if it’s urgent, we’ll see you as soon as possible. Book an appointment.

Frequently asked questions

Does an antibiotic cure a cavity or an abscess?

No. An antibiotic can slow down a spreading infection, but it doesn't remove the cause: the cavity, the infected nerve or the broken tooth are still there. If you only take the antibiotic, the problem comes back as soon as you stop. The tooth has to be treated.

Can I take an antibiotic on my own for toothache?

Not a good idea. Self-medicating can mask the problem, delay the real treatment and contribute to antibiotic resistance. For the pain, an over-the-counter painkiller helps in the meantime, but what you need is for the dentist to see you.

When does the dentist prescribe an antibiotic?

Mainly when there is an infection showing signs of spreading (significant swelling, fever, feeling generally unwell) or in patients with certain health conditions. Not in every case: often, by treating the tooth, no antibiotic is needed.