Each teething episode typically lasts about 3 to 8 days, with symptoms peaking in the days just before and after a tooth breaks through the gum. One study found that symptoms tend to cluster within an 8-day window: the 4 days before a tooth emerges, the day it erupts, and the 3 days after. That’s the timeline for a single tooth, but since babies get 20 primary teeth over a span of roughly two years, teething can feel like an ongoing process even though the acute discomfort comes and goes.
The 8-Day Window Per Tooth
Most parents notice fussiness, drooling, and gum sensitivity starting a few days before they can actually see or feel the tooth. The worst discomfort tends to hit right as the tooth is pushing through the gum tissue. Within a few days of breaking the surface, symptoms settle down. So while your baby may seem miserable for a stretch, each individual tooth’s rough patch is relatively short-lived.
Not every tooth causes the same level of trouble. The first teeth to arrive (usually the lower front incisors, around 6 months of age) and the molars tend to be the most uncomfortable. Molars have a broader surface area that has to push through more gum tissue, which is why many children have a particularly rough time between 25 and 33 months, when the large second molars come in. Incisors that arrive later in the sequence often cause less noticeable symptoms, possibly because your child has already been through it a few times and the gum tissue has adapted somewhat.
What Teething Actually Looks Like
The most reliable signs of teething are increased drooling, a desire to chew on anything within reach, red or swollen gums where the tooth is coming in, and general irritability. Some babies rub their cheeks or pull at their ears, especially during molar eruption, because the pain in the gums can radiate along the jaw.
Sleep disruption is common but usually follows the same 8-day pattern. Your baby may wake more frequently at night or resist naps for several days, then return to their normal sleep habits once the tooth is through. If sleep problems persist well beyond that window, teething probably isn’t the cause.
Fever and Diarrhea: What Teething Doesn’t Cause
Teething can nudge your baby’s body temperature slightly higher than usual, but it does not cause a true fever. A fever is defined as 100.4°F (38°C) or higher. If your baby’s temperature reaches that threshold, something else is going on, most likely an infection, and it shouldn’t be written off as teething.
The same applies to diarrhea. Teething alone won’t cause it. Some babies do have looser stools during teething because sore gums encourage them to nurse or drink more, which increases fluid intake. But actual diarrhea, especially if it persists, can lead to dehydration and needs attention regardless of whether teeth are coming in at the same time. It’s easy to assume every symptom during teething months is related to teeth, but overlapping illness is common in infants this age because their immune systems are still developing.
The Full Teething Timeline
Baby teeth generally start arriving around 6 months, though some infants show early signs of teething discomfort as young as 4 months. The 20 primary teeth typically finish coming in by age 2.5 to 3. Here’s the rough sequence most children follow:
- 6 to 10 months: Lower central incisors (bottom front teeth) appear first, followed by the upper central incisors.
- 9 to 16 months: Lateral incisors (the teeth flanking the front ones) come in on both top and bottom.
- 13 to 19 months: First molars erupt. These are often more painful than the earlier incisors.
- 16 to 23 months: Canines (the pointed teeth between incisors and molars) fill in.
- 25 to 33 months: Second molars arrive. These are the largest baby teeth and frequently the most uncomfortable.
These ranges vary widely. Some babies are born with a tooth already visible, while others don’t get their first until closer to 12 months. Both are normal.
Safe Ways to Ease the Discomfort
Since each episode is relatively brief, the goal is to keep your baby comfortable for those few days rather than eliminate the process entirely. Rubber or plastic teething toys give babies something safe to gnaw on, and the counterpressure on the gums can genuinely help. A damp washcloth twisted up and placed in the freezer for a few minutes makes an effective cold compress that babies can chew. The cold helps numb sore gums temporarily.
If your baby seems especially uncomfortable, infant acetaminophen or ibuprofen (for babies 6 months and older) can help, but check with your pediatrician for the right dose based on your child’s weight.
Products to Avoid
The FDA has warned against homeopathic teething tablets, particularly those containing belladonna. Testing found that some products from major brands contained levels of toxic compounds, including atropine and scopolamine, that far exceeded what was listed on the label. These products pose a real risk and should be discarded if you have them at home. Numbing gels containing benzocaine are also not recommended for infants, as they carry the risk of a rare but serious blood condition and can numb the throat, making swallowing difficult.
Amber teething necklaces, despite their popularity, have no evidence supporting pain relief and pose choking and strangulation hazards. The safest approaches remain the simplest: something cold, something to chew on, and occasional pain relief when needed.