Periodic breathing is breathing that comes in waves: stretches of stronger breaths alternate with short pauses, over and over in a regular cycle. It isn’t a blockage in the airway; it’s the body’s automatic breathing control overshooting and then correcting itself. Whether it matters depends almost entirely on who is doing it. It is harmless in a sleeping newborn or a hiker high in the mountains, but it can be a warning sign in an adult with a weak heart.
What Periodic Breathing Looks and Sounds Like
Each cycle starts with a burst of breaths that take extra effort. Then comes a pause that lasts about 5 to 18 seconds.1PubMed Central. Mechanisms of hypoxia-induced periodic breathing during sleep in humans The cycle repeats at a fairly steady length, so the pattern looks rhythmic rather than random.2PubMed Central. Mechanisms of hypoxia-induced periodic breathing during sleep in humans Just as a pause ends, oxygen in the blood is at its lowest and carbon dioxide at its highest.3PubMed. The morphology of periodic breathing in infants and adults
If you’re watching, you see the chest rise quickly for several breaths and then stay still. The pause usually ends on its own, and the skin normally stays pink during these brief stops. Timing the pauses with a phone timer gives a doctor something concrete to work with.
Babies and adults show slightly different shapes. Adults often show a crescendo-decrescendo pattern, with breaths growing and then shrinking.4PubMed. The morphology of periodic breathing in infants and adults In infants the breaths tend to start strong and only fade, without a slow build-up.5PubMed. The morphology of periodic breathing in infants and adults
It also helps to separate periodic breathing from the snoring-type of sleep apnea, called obstructive sleep apnea. In periodic breathing the chest stops moving during the pause. In obstructive apnea the chest keeps straining against a blocked throat, and the pause usually ends with a snort or gasp. The two need different treatment, so describing which one you saw matters. An irregular pattern with random pauses and no rhythm at all is something else again. It can suggest brain injury.6PubMed Central. Mandibular jaw movements as a non-invasive measure of respiratory effort during sleep: application in clinical practice
Why the Body Breathes in Waves
Your brain sets your breathing mainly by sensing carbon dioxide in the blood. When the system responds too strongly to small changes, it breathes off too much carbon dioxide.7PubMed Central. Enhanced expiratory rebreathing space for high loop gain sleep apnea treatment Carbon dioxide then drops below the level that drives breathing, and breathing pauses until it builds back up.8PubMed Central. Mechanisms of hypoxia-induced periodic breathing during sleep in humans Sensors in the neck arteries that detect oxygen and carbon dioxide largely set how long the breathing and pause phases last.9PubMed. Non-linear dynamics of human periodic breathing and implications for sleep apnea therapy
Delay makes this worse. When blood takes a long time to travel from the lungs to the brain, the brain reacts to old information.10PubMed. Cheyne-Stokes respiration during sleep in congestive heart failure Smaller body stores of oxygen and carbon dioxide also make blood levels swing more with each breath.11PubMed. Cheyne-Stokes respiration during sleep in congestive heart failure So anything that speeds the response, slows circulation, or shrinks reserves can tip breathing into waves.
Sleep makes it more likely. While you’re awake, conscious alertness keeps breathing steady regardless of the chemical signals. Asleep, breathing depends entirely on those signals, and without that backup the pattern shows up mostly at night.
Anyone’s breathing control can be pushed into waves if the conditions are right, so a healthy hiker and a person with heart failure can look the same. The cause behind the swing, not the swing itself, is what matters.
Periodic Breathing in Newborns and Premature Babies
In babies, periodic breathing comes mainly from a brainstem that is still maturing.12PubMed Central. Immature control of breathing and apnea of prematurity: the known and unknown Oxygen sensors that react too strongly make the baby overbreathe, then pause.13PubMed Central. Immature control of breathing and apnea of prematurity: the known and unknown In very premature babies, slow blood-vessel responses in the brain to carbon dioxide may be the main cause.14PubMed Central. Infant periodic breathing and apneic threshold The pattern usually fades as the baby’s nervous system matures.
A typical episode is a few seconds of pause between short bursts of normal breathing, and the baby looks calm and pink throughout. It tends to show up in active, light sleep, so you’re likely to see it while the baby dozes rather than when fully awake or feeding. The baby starts breathing again alone, without needing a touch or a sound.
Periodic breathing also doesn’t predict dangerous pauses. Among more than 1,100 serious breathing pauses recorded in premature babies, fewer than 0.6% happened during or within 2 minutes of periodic breathing.15Pediatric Research. Periodic Breathing and Apnea in Preterm Infants
Serious pauses in preemies, called apnea of prematurity, are a separate problem, often treated with caffeine.16Medical Express. Clinical pharmacology of caffeine citrate in preterm infants Caffeine stimulates the brain’s breathing centers and makes them more responsive to carbon dioxide.17Medical Express. Clinical pharmacology of caffeine citrate in preterm infants That reduces pauses and drops in oxygen without disturbing the baby’s sleep.18PubMed Central. Caffeine is a respiratory stimulant without effect on sleep in the short-term in late-preterm infants
Some signs need urgent help: a pause of 20 seconds or longer, lips or face turning blue, gray, or pale, or a baby who goes limp or is hard to wake. Gently stimulate the baby and call emergency services.
At the pediatrician’s office, say how long the pauses last and how often they happen, and whether the baby was asleep or feeding. Mention if the baby was born early. A short phone video is often more useful than a description.
Safe sleep rules still apply: back to sleep on a firm, flat surface, with no pillows or loose bedding. Home breathing monitors are not proven to prevent sudden infant death.
When It Signals a Problem in Adults
Brief periodic breathing while dozing off or in light sleep is common and usually not a concern.19PubMed. Sleep-induced periodic breathing and apnea: a theoretical study20PubMed. Sleep-induced periodic breathing and apnea: a theoretical study Cheyne-Stokes breathing is periodic breathing with pauses and waxing-waning breaths, and it is common in people with heart failure.21PubMed. Central sleep apnea and Cheyne-Stokes respiration A weak heart slows circulation, so the brain reads carbon dioxide late.22PubMed. Cheyne-Stokes respiration during sleep in congestive heart failure The weaker the heart’s pumping, the longer each cycle: about 49 seconds with near-normal pumping versus about 86 seconds with very poor pumping.23PubMed. Cheyne-Stokes respiration in heart failure: cycle length is dependent on left ventricular ejection fraction
The pattern can also strain the heart in return. Each pause lowers oxygen, and each recovery breath comes with a surge of stress hormones that raise heart rate and blood pressure. That repeated strain on a struggling heart is one reason the pattern is seen as more than a bystander sign.
More of it means a worse outlook. Sleep study reports list pauses per hour as the AHI (apnea-hypopnea index).24PubMed. Prognostic value of nocturnal Cheyne-Stokes respiration in chronic heart failure In heart failure, an AHI of 30 or more per hour marked a very high risk of cardiac death.25PubMed. Prognostic value of nocturnal Cheyne-Stokes respiration in chronic heart failure Periodic breathing during 10% or more of the daytime was linked to nearly four times the risk of dying.26PubMed. Daytime Cheyne-Stokes respiration in ambulatory patients with severe congestive heart failure is associated with increased mortality Longer Cheyne-Stokes time tracked with a blood marker of heart strain and with death within 6 months.27PubMed Central. Implications of Cheyne-Stokes breathing in advanced systolic heart failure
Other causes exist. Strokes in certain brain areas can trigger periodic breathing during sleep.28PubMed. Central periodic breathing during sleep in acute ischemic stroke Spinal cord injury can make people prone to central sleep apnea, pauses caused by the brain not signaling to breathe.29PubMed Central. Effect of acetazolamide on susceptibility to central sleep apnea in chronic spinal cord injury
Doctors sort harmless from concerning by asking when it happens, how much of the night or day it takes up, and whether the person has a heart, brain, or spinal condition. A few cycles while drifting off is a different situation from waves that continue through deep sleep or appear while the person is awake. The pattern alone doesn’t give a diagnosis; it prompts a look at the heart and brain, usually with a sleep study.
See a doctor if a partner notices pauses with heavy breathing during deep sleep, if the pattern appears while awake, or if there is new shortness of breath, ankle swelling, or poor exercise tolerance. Sudden weakness or trouble speaking needs emergency care.
A smartwatch or home device can suggest irregular breathing but cannot diagnose it. A lab or home sleep study is needed to confirm, and it’s worth bringing the device report to your doctor.
Periodic Breathing at High Altitude
Low oxygen at altitude makes you breathe harder.30MedLink Neurology. Central sleep apnea due to high-altitude periodic breathing You blow off carbon dioxide, which then suppresses breathing.31MedLink Neurology. Central sleep apnea due to high-altitude periodic breathing A pause follows, oxygen falls again, you partly wake and breathe hard, and the cycle repeats.32MedLink Neurology. Central sleep apnea due to high-altitude periodic breathing The main complaint is broken, unrefreshing sleep.
People often wake repeatedly, sometimes with breathlessness or a gasp, and may recall vivid dreams. A companion in the same tent may notice the pause and then the sudden deep breaths, which can look alarming but is typical in thin air.
It tends to be worse the higher you sleep. The thinner the air, the stronger the push to overbreathe, so the carbon dioxide swings grow larger. Sleeping much higher than where you spent the day adds to the effect, which is why guides often suggest sleeping lower than your high point.
The prescription drug acetazolamide reduces time spent in periodic breathing at altitude in healthy people.33PubMed Central. The effect of acetazolamide on sleep apnea at high altitude: a systematic review and meta-analysis In lowlanders 40 or older it cut breathing pauses by about 11 per hour and raised oxygen levels.34PubMed. Effect of altitude and acetazolamide on sleep and nocturnal breathing in healthy lowlanders 40 y of age or older. Data from a randomized trial It did not lengthen sleep or improve how deep it was.35PubMed. Effect of altitude and acetazolamide on sleep and nocturnal breathing in healthy lowlanders 40 y of age or older. Data from a randomized trial It helped both men and women, more so in men.36PubMed. Sex and acetazolamide effects on chemoreflex and periodic breathing during sleep at altitude
For travelers, the pattern usually eases as the body adjusts over several nights. Ascending gradually helps, and it’s worth asking a doctor about acetazolamide before the trip. Worsening headache, confusion, or breathlessness at rest signals altitude illness, not just periodic breathing.
How Periodic Breathing Is Treated
Adaptive servo-ventilation (ASV) is a bedside mask machine that adjusts pressure breath by breath to smooth the waves.37American Journal of Respiratory and Critical Care Medicine. Adaptive Pressure Support Servo-Ventilation: A Novel Treatment for Cheyne-Stokes Respiration in Heart Failure Standard CPAP delivers one steady pressure that holds the airway open, which suits a blocked throat. ASV instead gives more support when your breaths shrink and less when they grow. In one night it cut pauses from about 44 per hour to about 6, better than oxygen or standard CPAP.38American Journal of Respiratory and Critical Care Medicine. Adaptive Pressure Support Servo-Ventilation: A Novel Treatment for Cheyne-Stokes Respiration in Heart Failure
But in a large trial of people with weak-pumping heart failure, death rates were higher with ASV, about 35% versus 29%.39PubMed Central. Adaptive Servo-Ventilation for Central Sleep Apnea in Systolic Heart Failure A later trial using a different ASV approach found no added risk, though no survival benefit either.40PubMed. Adaptive servo-ventilation for sleep-disordered breathing in patients with heart failure with reduced ejection fraction (ADVENT-HF): a multicentre, multinational, parallel-group, open-label, phase 3 randomised controlled trial So the warning applies most to people whose hearts pump weakly, and the choice depends on the type of heart failure and pumping strength. It should be made with the cardiologist.
Before starting a machine, ask what your heart’s pumping strength (ejection fraction) is, whether ASV is safe for your type of heart failure, and whether CPAP or oxygen is an option. Improving heart failure treatment itself can also reduce the pattern.
Medicine is another route. In heart failure, acetazolamide roughly halved central pauses, from 49 to 23 per hour.41PubMed. Acetazolamide improves central sleep apnea in heart failure: a double-blind, prospective study People slept better and felt less tired during the day.42PubMed. Acetazolamide improves central sleep apnea in heart failure: a double-blind, prospective study Removing pauses has not been shown to help people live longer, so treatment aims at comfort, sleep, and the underlying disease.
Periodic Breathing Near the End of Life
Cheyne-Stokes breathing is a common pattern before death: deep, fast breaths that slowly become shallow, then a pause of several seconds before repeating.43Suncrest Hospice. What Is Periodic Breathing and When Is It a Concern? The brain’s breathing control weakens as the body shuts down. For families, seeing it is a signal that death may be near rather than an emergency. The person is usually deeply unresponsive and not feeling the struggle it looks like.
Pauses often get longer as the hours pass, and the breaths in between may become shallower. Other changes may appear alongside, such as cool hands and feet, mottled skin, and less response to voices. Together, more than any single one, these help a hospice nurse judge that death is close, although timing can’t be predicted exactly.
Families can tell the hospice nurse what they’re seeing; the nurse can explain timing and offer comfort medicine. Raising the head or turning the person can ease noisy breathing.
The same pattern occurs in people living for years with heart failure. In someone not known to be dying, it needs medical review.