My Baby Breathes Through Their Mouth
Medically reviewed by Dr. Michael Okonkwo, MD, FAAP · Board-Certified Neonatologist
Content reviewed against published AAP, AAP, Mayo Clinic guidelines
Last reviewed:
If your baby has been diagnosed with or you suspect breathes through their mouth, here is what the evidence says.
The short answer
Young babies are preferential nose breathers and typically only breathe through their mouths when crying. If your baby is consistently mouth breathing, it is usually due to nasal congestion from a cold or allergies. However, chronic mouth breathing in an infant or toddler, especially during sleep, can sometimes indicate enlarged adenoids, nasal obstruction, or other issues that warrant evaluation.
Key takeaways
- Young babies are preferential nose breathers and typically only breathe through their mouths when crying. If your baby is consistently mouth breathing, it is usually due to nasal congestion from a cold or allergies. However, chronic mouth breathing in an infant or toddler, especially during sleep, can sometimes indicate enlarged adenoids, nasal obstruction, or other issues that warrant evaluation.
- Usually normal when: Temporary mouth breathing during a cold or when the nose is stuffy, which resolves as congestion clears
- Call your doctor if: Your newborn cannot breathe through their nose at all and struggles to feed, as this could indicate a structural nasal obstruction requiring urgent ENT evaluation
- Varies by age — see the age-by-age breakdown below
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What Parents Should Know
According to AAP, Mayo Clinic guidelines, young babies are preferential nose breathers and typically only breathe through their mouths when crying. If your baby is consistently mouth breathing, it is usually due to nasal congestion from a cold or allergies. However, chronic mouth breathing in an infant or toddler, especially during sleep, can sometimes indicate enlarged adenoids, nasal obstruction, or other issues that warrant evaluation. At 0-3 months, newborns are obligate nose breathers for the first few months, meaning they strongly prefer to breathe through their nose. Nasal congestion from dried mucus, a cold, or narrow nasal passages can cause noisy breathing and may lead to mouth breathing. This can interfere with feeding since babies need to breathe through their nose while nursing or bottle-feeding. Saline drops and gentle suctioning can help. Persistent mouth breathing in a newborn, especially with feeding difficulty, should be evaluated to rule out choanal atresia (a blockage of the nasal passages) or other anatomical issues. It is generally considered normal when temporary mouth breathing during a cold or when the nose is stuffy, which resolves as congestion clears. However, you should contact your pediatrician promptly if your newborn cannot breathe through their nose at all and struggles to feed, as this could indicate a structural nasal obstruction requiring urgent ENT evaluation.
Normal vs. Concerning
By Age
What to expect by age
0-3 months
Newborns are obligate nose breathers for the first few months, meaning they strongly prefer to breathe through their nose. Nasal congestion from dried mucus, a cold, or narrow nasal passages can cause noisy breathing and may lead to mouth breathing. This can interfere with feeding since babies need to breathe through their nose while nursing or bottle-feeding. Saline drops and gentle suctioning can help. Persistent mouth breathing in a newborn, especially with feeding difficulty, should be evaluated to rule out choanal atresia (a blockage of the nasal passages) or other anatomical issues.
3-12 months
As babies grow, they develop the ability to switch between nose and mouth breathing more easily. Temporary mouth breathing during a cold is normal and expected. If your baby is chronically mouth breathing even when not sick, observe whether it occurs primarily during sleep (suggesting enlarged adenoids or tonsils) or all day. Persistent nasal congestion with clear drainage may indicate environmental allergies, though true allergies are uncommon before 12 months.
1-3 years
Chronic mouth breathing in toddlers is most commonly caused by enlarged adenoids, allergic rhinitis, or chronic congestion. Signs of adenoid enlargement include habitual mouth breathing, snoring, restless sleep, and sometimes a nasal quality to the voice. Adenoid tissue grows through early childhood and is largest around age 3-7. If your toddler snores regularly, sleeps with their mouth open, and seems to have pauses in breathing during sleep, your pediatrician may refer you to an ENT specialist for evaluation.
What to Tell Your Pediatrician
- Describe when you first noticed breathes through their mouth and how it has changed over time.
- Note your baby's current age and which age-specific patterns you are seeing.
- Mention if your baby or toddler seems to breathe through their mouth most of the time, even when not sick.
- Mention if your child consistently snores, sleeps with their mouth open, or has restless sleep with frequent position changes.
- Bring a list of any questions or observations you want to discuss at the appointment.
What Should You Do?
When to take action
- Temporary mouth breathing during a cold or when the nose is stuffy, which resolves as congestion clears
- Mouth breathing during crying, which is a normal response
- Brief mouth opening during deep sleep that is not habitual
- Your baby switches between nose and mouth breathing naturally and feeds without difficulty
- Your baby or toddler seems to breathe through their mouth most of the time, even when not sick
- Your child consistently snores, sleeps with their mouth open, or has restless sleep with frequent position changes
- You notice your child frequently has a dry mouth, cracked lips, or bad breath from chronic mouth breathing
- Your newborn cannot breathe through their nose at all and struggles to feed, as this could indicate a structural nasal obstruction requiring urgent ENT evaluation
- Your child has mouth breathing with observed pauses in breathing during sleep (sleep apnea), gasping or choking awake, excessive daytime sleepiness, or behavioral issues from poor sleep quality
What You Can Do at Home
- Keep track of when you notice breathes through their mouth — noting the time of day, duration, and any triggers can help your pediatrician.
- Remember that temporary mouth breathing during a cold or when the nose is stuffy, which resolves as congestion clears — this is generally within the range of normal.
- At 0-3 months, focus on observation rather than intervention unless your pediatrician advises otherwise.
- Follow any care instructions from your pediatrician. Keep a written log of symptoms to bring to appointments.
- While monitoring at home, seek immediate care if your newborn cannot breathe through their nose at all and struggles to feed, as this could indicate a structural nasal obstruction requiring urgent ENT evaluation.
Related Resources
Breathing Difficulty Triage
Assess breathing concerns and know when to seek emergency care.
Month-by-Month Development
Detailed monthly development guides from birth through 24 months.
When to Call the Doctor
General guide on when to call the pediatrician, visit urgent care, or go to the ER.
Frequently asked questions
Is breathes through their mouth normal?
When should I call the doctor about breathes through their mouth?
When is breathes through their mouth normal?
What causes breathes through their mouth?
What should I mention to my pediatrician about breathes through their mouth?
Is breathes through their mouth normal at 0-3 months?
Is breathes through their mouth normal at 3-12 months?
Should I go to the ER for breathes through their mouth?
Does breathes through their mouth go away on its own?
References
- [1]HealthyChildren.org. Snoring, Mouth Breathing, and Sleep Apnea in Children. AAP
- [2]Marcus CL, et al. Diagnosis and Management of Childhood Obstructive Sleep Apnea Syndrome. Pediatrics, 2012. AAP
- [3]Mayo Clinic. Nasal Congestion in Infants. Mayo Clinic
Doctor Visit Checklist
Bring this checklist to your next pediatrician visit to discuss My Baby Breathes Through Their Mouth.
Things to mention
- Describe when you first noticed breathes through their mouth and how it has changed over time.
- Note your baby's current age and which age-specific patterns you are seeing.
- Mention if your baby or toddler seems to breathe through their mouth most of the time, even when not sick.
- Mention if your child consistently snores, sleeps with their mouth open, or has restless sleep with frequent position changes.
- Bring a list of any questions or observations you want to discuss at the appointment.
Observations to share
- Your baby or toddler seems to breathe through their mouth most of the time, even when not sick
- Your child consistently snores, sleeps with their mouth open, or has restless sleep with frequent position changes
- You notice your child frequently has a dry mouth, cracked lips, or bad breath from chronic mouth breathing
Urgent signs to report immediately
- Your newborn cannot breathe through their nose at all and struggles to feed, as this could indicate a structural nasal obstruction requiring urgent ENT evaluation
- Your child has mouth breathing with observed pauses in breathing during sleep (sleep apnea), gasping or choking awake, excessive daytime sleepiness, or behavioral issues from poor sleep quality
My notes
From ismybabyalright.com — free, evidence-based baby health guides
All content follows our editorial policy and is reviewed against published clinical guidelines.
2,705 evidence-based guides6 authoritative medical sources5 medical advisory board members
Related Resources
Bottom line
Most cases of breathes through their mouth are normal. Talk to your pediatrician if your newborn cannot breathe through their nose at all and struggles to feed, as this could indicate a structural nasal obstruction requiring urgent ent evaluation.
Trust your instincts. If something feels wrong, reach out to your pediatrician. Worrying about your baby means you care — that is a good thing.
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