Enlarged tonsils in adults: snoring, sleep apnea and when surgery helps

Enlarged tonsils in adults can narrow the back of the throat enough to cause snoring and, in some people, obstructive sleep apnea. Doctors grade tonsil size by how much of the throat opening the tonsils fill, and that grade helps decide what to do next. For adults with large tonsils and sleep apnea, removing the tonsils can work well, though CPAP is usually tried first.

Can enlarged tonsils cause snoring and sleep apnea in adults?

Enlarged tonsils can cause snoring and sleep apnea in adults because they take up room in the airway at the back of the mouth. Cleveland Clinic says larger-than-normal tonsils can block your airway, leading to snoring and sleep apnea. The National Heart, Lung, and Blood Institute (NHLBI) lists large tonsils, along with a large neck or tongue, as features that can narrow the upper airway or make it more likely for the tongue to block it while you sleep.

When you fall asleep, the muscles that hold the throat open relax. If the tonsils already fill much of the space, there's less margin before the airway narrows enough to vibrate (snoring) or close for a few seconds at a time (apnea). Our guide to why people snore when they're not overweight covers other airway features that work the same way.

Tonsil size does seem to track with how severe sleep apnea is. A 2018 study in Laryngoscope looked at 83 adults at the University of Washington who had throat surgery for sleep apnea, including tonsil removal. The group had a mean age of 43, was 61% male and had severe sleep apnea on average. After adjusting for age, sex, body mass index and smoking, a higher tonsil grade on exam was linked to a higher apnea-hypopnea index (AHI), the number of breathing pauses and shallow breaths per hour of sleep. Oddly, the actual measured volume of the removed tonsils was not. The authors suggest that how much of the throat the tonsils fill matters more than their raw size.

How do doctors grade tonsil size?

Doctors grade tonsil size by looking in your mouth and estimating how much of the throat opening, the oropharynx, the tonsils fill. One system used in adults is the Brodsky scale. The 2018 Laryngoscope study describes it this way:

There's no single official cutoff for "enlarged". A 2016 review of adult tonsil surgery for sleep apnea included tonsils described as grades 2 to 4, and a 2022 Swedish trial used a similar tonsil size score from the Friedman staging system, enrolling people with sizes 2, 3 or 4. The grade is an estimate made by eye, which is one reason the 2018 study's finding that it tracks sleep apnea severity is interesting.

You can look at your own tonsils in a mirror, but that isn't a formal grade. If you think your tonsils are large, ask a doctor to take a look.

What causes enlarged tonsils in adults?

Enlarged tonsils in adults are often just how someone is built, but infections and, rarely, other conditions can also cause them. Cleveland Clinic notes that tonsils get bigger during childhood and can shrink as you get older, which is why large tonsils are more common in children. A 2025 study from Southwest Finland found a similar pattern in adults: the rate of surgery for large tonsils fell with age.

Cleveland Clinic lists several causes of swollen or inflamed tonsils:

• Tonsillitis, an infection of the tonsils by bacteria or viruses, which can be short-term or long-term (chronic)
• Strep throat, a bacterial infection
• Mononucleosis, caused by the Epstein-Barr virus
• A peritonsillar abscess, a pocket of infection that pushes one tonsil toward the other side of the throat

One pattern deserves prompt attention. In the 2025 Finnish study, 12.7% of patients with asymmetric tonsils, where one is bigger than the other, had a cancer, most often lymphoma. Cleveland Clinic also notes that tonsil cancer, often linked to HPV, can cause tonsil pain, a lump in the neck and blood in your saliva. If one tonsil is noticeably larger, see a doctor rather than waiting.

How common is surgery for large tonsils in adults?

Surgery for large tonsils in adults is uncommon. The 2025 study from the Hospital District of Southwest Finland reviewed records from 2004 to 2018 and found an incidence of 8.49 tonsil removals for enlarged tonsils per 100,000 adults per year. Only 9.5% of adults who had tonsil surgery there had enlarged tonsils. Among those, snoring was the most common reason for surgery, at 30.8%.

Cleveland Clinic says tonsillectomy is still done more often in children, but that up until the 1980s it was frequently done for tonsillitis, and providers now do it more often to treat sleep apnea.

Does tonsillectomy help adults with sleep apnea?

Tonsillectomy can help adults with sleep apnea when the tonsils are clearly enlarged, and the results are often good. A 2016 systematic review and meta-analysis in Laryngoscope pooled 17 studies with 216 adults, mean age 34, who had their tonsils removed as the only treatment. Their AHI dropped by 65.2%, from 40.5 to 14.1 events an hour. Their lowest overnight oxygen level rose from 77.7% to 85.5%, and daytime sleepiness scores roughly halved.

The review found that how severe the sleep apnea was beforehand made a big difference. In the 54 patients with individual data, among people with an AHI under 30 before surgery, all 25 met the authors' definition of success (an AHI under 20 and at least a 50% drop), and 21 of the 25 were classed as cured. Among people starting at 30 or higher, 72.4% met the success definition and 34.4% were cured. The authors concluded that tonsillectomy alone can work, especially in people with large tonsils and mild to moderate sleep apnea.

The strongest single study is a randomized trial from Stockholm, published in JAMA Otolaryngology in 2022. It included 93 adults, mean age 42 and 86% men, with large tonsils and moderate to severe sleep apnea. Half had tonsillectomy alone and half had a modified uvulopalatopharyngoplasty (UPPP), which removes the tonsils and also shortens the uvula and stitches the tissue around the tonsil area closed. Six months later, AHI had fallen by 56% in the tonsillectomy group, from 56.9 to 24.7, and by 43% in the UPPP group, from 51.0 to 28.0. The larger operation wasn't more effective, and the authors suggest the less extensive tonsillectomy could be considered instead for this group.

The long-term picture is less clear. A small Finnish study of 21 adults who had tonsillectomy for sleep apnea, with follow-up of up to about 14 years, found a success rate of 47.6%. None of the patients followed for longer than a year counted as a success. That's a small group, but it's a good reason to have a repeat sleep test after surgery rather than assuming the problem is solved. Our guide to snoring surgery explains the other procedures you might hear about.

When is tonsillectomy considered for sleep apnea?

Tonsillectomy is usually considered after CPAP has been tried, or when there's another reason to remove the tonsils. A 2021 clinical practice guideline from the American Academy of Sleep Medicine (AASM) addresses adults with sleep apnea and a major upper airway abnormality, and it names large tonsils as one example. It suggests recommending CPAP as the first treatment before a surgery referral, because CPAP carries minimal risk compared with surgery, while acknowledging that surgery in this group shows a clinically significant benefit.

The guideline adds that other problems, such as chronic tonsillitis, may justify talking about surgery first. It also says people with major anatomic obstruction who refuse CPAP should discuss a surgical referral with their provider. And it strongly recommends that clinicians discuss a sleep surgeon referral with adults who have sleep apnea, a body mass index under 40 and can't tolerate or don't accept CPAP. If you're struggling with your machine, see getting used to CPAP before deciding it isn't for you.

The NHS also lists surgery to help your breathing, such as removing large tonsils, among the other treatments sometimes used for sleep apnea, alongside mouth devices and nerve stimulation. Our overview of sleep apnea treatment options compares them.

What is recovery from adult tonsillectomy like?

Recovery from adult tonsillectomy usually takes about two weeks and tends to be harder than for children. Cleveland Clinic says most people reach full recovery in about two weeks, that recovery is generally more difficult for adults, and that it's best to take at least 10 days off work. Soft, cool foods and plenty of fluids help, and crunchy or spicy foods are best avoided for a while.

Cleveland Clinic lists the possible risks, which are rare but real: excessive bleeding during or after surgery, swelling of the tongue or roof of the mouth, wound infection, a reaction to anesthesia, changes in taste, dehydration, needing further procedures, and injury to the lips, tongue or teeth. It advises calling your provider if you develop bleeding, difficulty breathing, or pain that gets worse after five days or doesn't improve with pain medication.

When should you see a doctor?

See a doctor if you snore loudly and also have signs of sleep apnea, whatever your tonsils look like. The NHS lists these as the main symptoms:

• Breathing that stops and starts while you sleep
• Gasping, snorting or choking noises in your sleep
• Waking up a lot, and feeling very tired during the day

A sleep study measures your AHI. The NHS describes an AHI of 5 to 14 as mild, 15 to 30 as moderate and over 30 as severe. The NHS says you can usually do the test at home; see our guide to the home sleep apnea test. Our list of sleep apnea warning signs covers the daytime clues too.

Also see a doctor promptly if one tonsil is much bigger than the other, if you have a lump in your neck, or if you notice blood in your saliva. A nose that's blocked most nights is worth raising at the same visit. If you're pregnant and snoring has started or gotten worse, mention it to your midwife or doctor. If your tonsils are often sore, or you get tonsil stones, our guide to mouth breathing and tonsil stones may help.

This article is general information, not medical advice. Only an exam and a sleep study can tell you whether your tonsils are behind your snoring and what the right treatment is.

Read next

• Snoring surgery: procedures, side effects, recovery and who it helps
• Sleep apnea treatment options
• 10 reasons you snore, and what to try for each

* This content is for informational and educational purposes only and is not medical advice. It is not intended to diagnose, treat, cure or prevent any disease or health condition. Talk to a qualified healthcare provider about your health.