Constant yawning is your brain’s attempt to regulate itself, and it usually comes down to one of a few causes: poor sleep, overheating, medication side effects, or sometimes an underlying health condition. Adults yawn about nine times a day on average, though some people yawn up to 20 times and that’s still within a normal range. The threshold doctors use for “excessive” yawning is three or more yawns within a 15-minute window, happening repeatedly throughout the day. At that frequency, something beyond ordinary tiredness is likely driving it.
What Yawning Actually Does
The old idea that yawning pulls more oxygen into your lungs has largely been replaced by a more compelling explanation: brain cooling. When you yawn, the wide gaping of your mouth and the deep inhale that follows create a rush of cool air that helps lower the temperature of blood circulating to your brain. Your brain runs best within a narrow temperature range, and yawning appears to be one of the body’s tools for keeping it there.
This explains a lot of the patterns people notice. You yawn more in warm rooms, less in cold ones. You yawn more during mentally demanding tasks that heat up brain activity. And you yawn more when you’re sleep-deprived, because poor sleep disrupts your body’s ability to regulate temperature on its own. The yawn is essentially a biological reset button for an overheating brain.
The reflex itself is coordinated by the hypothalamus, the part of the brain responsible for keeping your internal environment stable, including body temperature, hunger, and sleep cycles. A specific cluster of neurons there initiates the motor sequence of a yawn, while a network in the brainstem that governs wakefulness and arousal plays a supporting role. This is why yawning tends to spike during transitions between alertness and drowsiness.
Sleep Deprivation and Sleep Apnea
The most common reason you can’t stop yawning is simply that you’re not getting enough quality sleep, even if you think you are. A prospective study comparing people with severe obstructive sleep apnea to those without it found that yawning frequency was significantly higher in the apnea group. Yawning correlated with lower oxygen saturation during sleep and with higher daytime sleepiness scores. In other words, the worse your sleep quality, the more your brain compensates by yawning throughout the day.
Sleep apnea is worth considering if your yawning is relentless and you also wake up feeling unrefreshed, have morning headaches, or have been told you snore heavily. Many people with sleep apnea don’t realize they have it because the breathing disruptions happen while they’re asleep. The excessive yawning during the day is one visible signal that nighttime sleep is being interrupted dozens or even hundreds of times.
Medications That Trigger Yawning
If your nonstop yawning started around the time you began a new medication, that’s probably not a coincidence. Antidepressants that increase serotonin levels are well-documented triggers. A prospective study of 150 patients starting these medications for the first time found that the rate of excessive yawning nearly tripled, going from 5.4% before treatment to 15.4% after. The severity of yawning also increased and correlated with the severity of depression itself.
Serotonin-boosting antidepressants are the most studied culprits, but other medications that affect brain chemistry can have the same effect. If the yawning is bothersome, your prescriber may be able to adjust your dose or switch to a different medication. Don’t stop taking anything on your own, but it’s worth bringing up at your next appointment.
Migraines and the Yawning Warning Sign
For people who get migraines, excessive yawning can be an early warning that an attack is building. In a study of 339 migraine patients, about 11% reported repetitive yawning in the premonitory phase (the hours before head pain begins), and 24% experienced it during the headache itself. Another 10% had it in both phases.
If you notice a pattern of uncontrollable yawning followed by a migraine within a few hours, that’s your brain signaling a shift in neurological activity before the pain hits. Recognizing this can actually be useful. Some people find that taking their migraine medication during the premonitory phase, before the headache fully develops, makes it more effective.
Neurological and Cardiovascular Causes
Less commonly, excessive yawning can point to a neurological condition. People with multiple sclerosis yawn significantly more than healthy controls, according to a polygraphic study that tracked yawning objectively rather than relying on self-reports. About a third of the MS patients in that study had brainstem involvement, though the relationship between brainstem lesions and yawning turned out to be more complex than a simple cause-and-effect.
Yawning is also a recognized symptom of vasovagal episodes, those pre-fainting spells where your blood pressure drops suddenly. The vagus nerve, which controls heart rate and blood pressure, becomes overactive and causes a cascade of symptoms: lightheadedness, nausea, tunnel vision, and yawning. If your bouts of yawning come alongside feeling faint or clammy, that vagus nerve response is a likely explanation.
In rare cases, pathological yawning can reach extreme levels, with some documented cases exceeding 100 yawns per day. Even yawn frequencies below the standard threshold can be considered abnormal if they consistently occur alongside other episodic symptoms like seizures or migraine attacks.
How to Stop a Yawning Fit
Since yawning appears to be driven by brain temperature, the most effective immediate strategies target cooling. In an experimental study, holding a cold pack against the forehead reduced contagious yawning to just 9% of participants. Even simpler: breathing exclusively through your nose (both inhaling and exhaling) eliminated contagious yawning entirely in the same study. Nasal breathing cools the blood flowing near the brain’s surface more efficiently than mouth breathing, which may explain why it short-circuits the yawning reflex so effectively.
For longer-term relief, the fix depends on the cause. If sleep deprivation is driving it, no breathing trick will substitute for actually getting better sleep. If a warm office is the problem, stepping outside for a few minutes of cool air can reset things. If you’re yawning excessively and can’t identify an obvious trigger like poor sleep, a hot room, or a new medication, it’s worth mentioning to your doctor, particularly if it’s accompanied by other symptoms like fatigue, dizziness, headaches, or numbness.