Scalloped Tongue: Causes, What It Means and When to Get Help

A scalloped tongue has wavy or rippled dents along its sides. [1] Doctors may call it a crenated tongue, and you may also see it called a rippled or piecrust tongue. [4] [5]

The dents form when your tongue presses against your teeth. [1] [2] They are not harmful on their own, but they can be a clue to something else, so it is worth mentioning them to a doctor or dentist. [1] This guide covers the main causes, what to look for and what helps.

What does a scalloped tongue look like?

Look at the sides of your tongue in a mirror. A scalloped tongue has a row of small, rounded dents along the edges, where it presses against your teeth. [1] [2] It is rarely painful, though some people have soreness or redness. [5]

How common it is depends on the study. In 244 bank workers in Japan, 51% had some dents, and most were mild. [8] In 600 dental patients in Malaysia, about 8% had a scalloped tongue. [13] Studies don’t all measure it the same way, so there is no single figure.

What causes a scalloped tongue?

Anything that makes your tongue larger, or pushes it against your teeth, can cause dents. [1] [2] Here are the main causes and the other signs that can point to each one:

Dehydration and smoking are also listed as causes, though we found little research on either. [1] [5]

The evidence on grinding is mixed. Grinding and clenching are often named as the leading cause. [5] But in the study of 244 bank workers, dents were no more common in people who knew they clenched or ground their teeth, though that study relied on what people reported and did not measure grinding directly. [8] A small study of 24 people found those with dents had wider tongues, but did not press harder against their teeth. [7] For some people, the shape and width of the tongue may be part of the answer.

Rarer causes. A tongue that slowly gets bigger, known as macroglossia, can come from conditions such as amyloidosis, where abnormal proteins build up, or acromegaly, which is too much growth hormone. [3] Tell a doctor if your tongue seems to be growing, or if it makes speaking or eating harder.

Is a scalloped tongue a sign of sleep apnea?

It can be, but it isn’t proof. Sleep apnea is when your breathing stops and starts while you sleep. [10] Here is what the studies found:

• In 1,261 adults at higher risk who all had a sleep study, about 40% of those with sleep apnea had a scalloped tongue. So did about 21% of those without it. [4]
• In 1,130 adults in Japan from the general population, those with moderate to severe scalloping had more than twice the odds of repeated low oxygen during sleep. [6]
• In 160 people having a sleep study in Brazil, a scalloped tongue was linked to severe sleep apnea, especially in people with a neck size of 40 cm or more. [14]

So in that first study, most people with sleep apnea did not have a scalloped tongue, and many people with one did not have sleep apnea. You can’t tell from your tongue alone.

See a doctor if your breathing stops and starts while you sleep, if you make gasping or choking noises at night, or if you always feel very tired during the day. [10] Sleep apnea can also make it hard to concentrate. [10] Our guide to what causes brain fog covers other reasons for that.

Can thyroid problems cause a scalloped tongue?

Yes. An underactive thyroid can make the tongue larger, and some people with thyroid problems notice scalloping. [1] [3] Hashimoto’s disease can cause an underactive thyroid. Our guide to Hashimoto’s symptoms covers the other signs.

A scalloped tongue doesn’t mean you have a thyroid problem. Doctors can’t diagnose an underactive thyroid from symptoms alone, but a blood test can help confirm it. [11] If you also feel tired, cold or are gaining weight, ask whether you need one. Once you have results, our guide on how to read blood test results can help.

How do doctors find the cause?

A doctor or dentist will look at your tongue, ask about your symptoms and go through your medical history. [5] What happens next depends on what they find. It might include:

• blood tests, for example for thyroid function or vitamin B12 [11] [12]
• a sleep test, which you can usually do at home, if sleep apnea seems possible [10]
• a check of your teeth and jaw, if grinding or a jaw problem seems possible
• less often, a scan or a tissue sample (biopsy) [5]

How do you get rid of a scalloped tongue?

There is no treatment for the dents themselves. The aim is to treat the cause, and that usually helps them go away. [1] Depending on the cause, this might mean:

• a mouth guard, if you grind or clench your teeth [1]
• a CPAP machine or another sleep apnea treatment [1] [10]
• thyroid hormone medicine, for an underactive thyroid [11]
• treatment for low B12 or folate, which works best when started early [12]
• medicine for inflammation or an immune condition [1]

Things you can do at home include drinking enough water, not smoking or using tobacco, looking after your teeth and mouth, and managing stress. [1] These may help, but they won’t fix a medical cause, so it is still worth getting checked.

We found no good research on how long the dents take to fade. It is likely to depend on the cause, and if your tongue is naturally wide, they may not change much.

What should you write down for your doctor?

A scalloped tongue is easier to explain with a few notes and a photo. Write down:

• when you first noticed the dents, and whether they come and go
• any soreness, swelling, or trouble speaking or eating
• snoring, gasping at night or feeling very tired during the day. Ask anyone who sleeps near you
• jaw pain, worn teeth or morning headaches
• other changes, such as a dry mouth, feeling cold, weight changes or pins and needles
• your medicines and supplements, and when you started them

Photos of your tongue in the same light can help you see whether it is changing. Our free symptom tracker gives you one place to keep your notes.

If writing it down is too much, you can tell Juno what you notice by voice or text. Juno logs it and turns your notes into a dated summary to take to your appointment. See how the Juno symptom tracker works.

When is a swollen tongue an emergency?

Dents along your tongue are usually not an emergency. [1] Sudden swelling is different, because it can affect your breathing. [9] It can come from an allergic reaction or from a medicine, most often a type of blood pressure medicine called an ACE inhibitor. [9]

This article is for general information only and does not replace advice from your own clinician. Juno is a health assistant, not a medical provider.

Last updated 6 November 2026