For several months, a 46-year-old man kept noticing swelling in front of both ears, most prominently on the left. It brought a sense of fullness and mild discomfort, and it usually faded on its own within a few hours.
The cause turned out to be a habit. He regularly puffed his cheeks hard against pursed lips, creating a Valsalva-type pressure surge to relieve discomfort in his jaw joints, and he used the same maneuver during episodes of anxiety. A CT scan showed air inside the ducts of both parotid glands, within the glands themselves and in the overlying facial tissue.
Doctors at the Kirk Kerkorian School of Medicine at the University of Nevada, Las Vegas, described the case of self-induced pneumoparotid in Sage Open Medical Case Reports, published online March 31, 2026.
How Puffing Your Cheeks Can Push Air the Wrong Way
The parotid glands are major salivary glands. According to Harvard Health Publishing, they sit in the upper part of each cheek near the ear, and each one drains through a duct that opens on the inside of the cheek near the upper molars. That channel is called Stensen's duct.
Several defenses normally keep air out, the UNLV authors explained, including the duct's narrow opening, folds of lining tissue that act like a one-way valve, and compression from the cheek's buccinator muscle. High enough pressure inside the mouth can overwhelm those defenses and force air backward into the gland. That can stretch the gland and rupture tiny saliva-producing sacs, letting air leak into nearby tissue.
Pressure is the key. A Cureus case report noted that pressure inside the mouth typically measures 2 to 3 mmHg but can reach 140 mmHg during activities like glassblowing. The UNLV authors list cheek puffing, glassblowing, playing wind instruments, and forceful coughing or sneezing among the activities patients may report, along with recent dental procedures and CPAP machines.
Clues That Surfaced Only with the Right Questions
The man had no fever, pus or other signs of infection. At an otolaryngology visit, doctors found mild, soft swelling on both sides without redness or warmth, along with subtle crepitus, a crackling feel under the skin, over the left gland. His blood tests were normal.
His cheek-puffing habit emerged only after targeted questioning. The authors wrote that patients may initially consider such behaviors trivial or unrelated to their symptoms.
The CT scan showed small gas pockets along both Stensen's ducts, in both glands and under the facial skin, especially in front of his left ear. It found no abscess, no significant inflammation, no air tracking deep into the neck, and no pneumomediastinum, or air in the central chest. The authors noted that a specialized puffed-cheek CT, in which patients blow out their cheeks during the scan, can highlight subtler cases.
Getting the diagnosis right matters because pneumoparotid is often confused with more common causes of parotid swelling, such as infection. Recognizing it can spare patients unnecessary antibiotics and invasive procedures, the authors wrote.
A Rare Condition with a Strange Past
Pneumoparotid is uncommon. A systematic review in the Journal of Clinical Medicine identified 170 patients across 126 studies, with an average age of 28.4. Swelling was reported in 84.7% and pain in 35.9%. Crepitus appeared in 40%, and frothy saliva from the duct opening in 39.4%. Habits such as blowing out the cheeks accounted for 23.5% of cases, and no cause was identified in 20%. Treatments included antibiotics in 30% of patients, behavioral therapy in 25.9% and surgery in 8.2%.
Self-induced cases are reported most often in children and adolescents, the UNLV team noted, which makes a 46-year-old patient less typical and adds to a limited body of adult reports.
The condition also has an odd history. A literature review of 54 patients traced the term to a description by Hyrtl in 1865. It also recounted a 1915 episode in which soldiers in the French Foreign Legion in North Africa deliberately blew into small bottles to bring on the swelling and avoid duty. That review found air under the skin was the most common complication, seen in 24.1% of patients, sometimes with pneumomediastinum in 5.5%. Surgery was rarely used as a definitive fix.
The Cureus report described a man who developed both pneumoparotid and pneumomediastinum after inflating an air mattress with his mouth.
Stopping the Habit Was the Treatment
The UNLV doctors managed the case conservatively. They counseled the man to stop the pressure-generating maneuvers and warned about possible complications if he continued. He needed no antibiotics or surgery.
His swelling resolved fully, and he had no further episodes over three months of follow-up. His jaw discomfort was mild and improved after he stopped the habit, though he was advised to seek dental evaluation if it persisted or worsened. Doctors also advised follow-up with his primary care provider and mental health services if his anxiety continued.
Recurrence is not uncommon when the triggering behavior continues, the authors cautioned, so monitoring over several months is reasonable. Because this is a single case, it does not show how often cheek-puffing causes the condition in adults. Anyone with repeated swelling in front of the ears, particularly with a crackling sensation, should see a clinician and mention any habits that raise pressure in the mouth.
Key Questions Answered
What is pneumoparotid?
Air trapped in a parotid salivary gland or its duct, usually forced in by high pressure inside the mouth.
What caused the man's swelling?
A habit of puffing his cheeks against pursed lips, which he used to ease jaw-joint discomfort and during episodes of anxiety.
How was it diagnosed?
Through targeted questioning, an exam that found subtle crackling over the left gland, and a CT scan showing air in the ducts, glands and facial tissue.
Is it dangerous?
Often it is not, but air can spread under the skin and, less commonly, into the central chest.
How was it treated?
He stopped the habit. The swelling resolved without antibiotics or surgery, with no recurrence over three months.
Who gets pneumoparotid?
It is rare, and self-induced cases are most often reported in children and adolescents, but adults can develop it too.
