How do I know if my baby is teething?
How to tell a tooth from an illness, and what actually soothes sore gums.
In short
The first tooth usually appears around 6 months, and anywhere from about 3 months to after the first birthday is normal. Drooling, chewing, one red cheek and sore gums point to teething. A fever of 38°C or above, diarrhoea or vomiting mean illness, not a tooth.
- The two bottom front teeth tend to come first, and late teething is almost never a problem.
- A teething ring cooled in the fridge, never frozen, or a clean cool damp facecloth genuinely helps.
- Ask your pharmacist before using any teething gel, granules or pain relief.
- Amber teething necklaces do not work and are a choking and strangulation risk.
- Start brushing twice a day as soon as the first tooth appears.
Teething gets blamed for everything. The bad night, the off feed, the mystery grizzle, the nappy that made you open a window. Some of that really is teething. A surprising amount of it isn't, and knowing the difference matters more than any teething product you can buy.
When do babies start teething?
The first tooth usually appears around 6 months, but anywhere from about 3 months to after the first birthday is normal. The two bottom front teeth tend to come first. A few babies are even born with a tooth, which is startling but fine.
If your baby is late to the party, don't worry. Late teething is almost never a problem. The teeth come when they come.
What are the signs of teething?
When a tooth is genuinely on the move, you'll usually see some mix of:
- Heavy drooling, often enough to soak a bib or three
- Chewing on everything within reach, including you
- One red flushed cheek
- Red sore gums where the tooth is coming
- More irritable and clingy than usual
- Slightly disturbed sleep
- Sometimes a slightly raised temperature
Note the word slightly. That last one is where the biggest teething myth lives.
Does teething cause a fever, diarrhoea or vomiting?
Teething does not cause a true fever of 38°C or above. It doesn't cause diarrhoea and it doesn't cause vomiting. Those are signs of illness, not a tooth, no matter what the neighbour or the forum says.
If they appear, treat it as illness and seek advice, especially in a baby under 3 months with a temperature of 38°C or above. Blaming a tooth is the easiest way to miss something that needs looking at.
| Points to teething | Points to illness, get advice |
|---|---|
| Drooling and chewing | Fever of 38°C or above |
| Red cheek and sore gums | Diarrhoea or vomiting |
| Clingy but consolable | Unusually drowsy or floppy |
| Slightly raised temperature | Refusing feeds for a day or more |
When in doubt, ring your GP or PHN. Nobody has ever been given out to for checking.
What helps a teething baby?
The good news is that the things that work are mostly free:
- A teething ring cooled in the fridge, never frozen
- Chewing on a clean cool damp facecloth
- Gently rubbing the gum with a clean finger
- If your baby is already weaned, cool soft foods
- Extra comfort and patience, in industrial quantities
- Wiping the chin often and a rotation of drool bibs to head off a drool rash
None of it is glamorous. All of it beats most of what's on the pharmacy shelf.
Can I give my baby teething gel, granules or pain relief?
Talk to your pharmacist before using any teething gel or granules. Some of what's sold for teething is not recommended for babies, and the pharmacist will know which is which.
The same goes for pain relief. Ask your pharmacist, GP or PHN before giving any, and follow the label exactly.
And one hard no: amber teething necklaces don't work and they're a choking and strangulation risk. Don't use them, no matter how lovely they look on Instagram.
When should I start brushing my baby's teeth?
Once the first tooth appears, start brushing it twice a day. Ask your dentist or PHN about the right toothpaste for under-2s.
Free public dental care in Ireland starts with school screenings, but you can register a child with a dentist much earlier, and it's worth doing.
How do I know if my baby's bad night was a tooth?
Often you can't tell in the moment. A tooth usually only explains itself in hindsight, once it has actually appeared and you look back at the week before it. Lullagram lets you log the grim nights and the off-form days, so when the pattern turns out to be a tooth you can see it looking back, and both parents know exactly what kind of night it was without the 6am debrief. It is free to try on Android, iPhone and web.
The HSE has more on teething if you want the official guidance alongside the practical.
Sources and guidance
This guide is written to be consistent with the official guidance below. It is general information for parents in Ireland, not medical advice. Links checked 17 September 2026.
A great app that has made them late night feeds and nappy changes easier. The fact my account links with my partner means we both know how baby is doing and takes away the guess work at night of what time baby is due or has been feed. Looking forward to using the other elements of the app as our little man grows.