When to take your baby to the ER for RSV

Most RSV infections in infants are managed at home and resolve within 1–2 weeks. But RSV is also the leading cause of infant hospitalization in the US, and the line between "uncomfortable cold" and "medical emergency" can move fast — especially in babies under 6 months.

This guide gives you concrete, specific signs to watch for. Print it. Keep it somewhere accessible during RSV season.

Go to the ER immediately

Any of these signs warrants an immediate ER visit or 911 call:

• Blue or gray color around the lips, fingernails, or skin — this is cyanosis and means the body is not getting enough oxygen
• Ribs showing with each breath (subcostal or intercostal retractions) — the skin between or below the ribs pulling in sharply
• Nostrils flaring dramatically with each breath
• Grunting with each exhale — a sound like a short grunt or grunt at the end of each breath
• SpO₂ below 90% on a pulse oximeter, or SpO₂ below 95% that won't recover
• Apnea — pauses in breathing, even brief, especially in infants under 2 months
• Unresponsive or unusually limp — won't wake up, extremely difficult to rouse, floppy body tone
• Breathing rate over 70 breaths/minute at rest in a calm infant

Call your pediatrician today (or go to urgent care)

These signs are not immediate emergencies but require same-day evaluation:

• Fever above 100.4°F (38°C) in an infant under 3 months — full stop, call regardless
• Breathing rate consistently above 60 breaths/minute at rest
• Wheezing — a high-pitched sound on exhale, audible without a stethoscope
• Eating less than half of usual for two or more feedings in a row
• No wet diaper in 6–8 hours (sign of dehydration)
• No tears when crying
• Cough is significantly worse on day 3 or 4 (RSV typically peaks around day 5)
• SpO₂ consistently below 95%
• Your instinct tells you something is wrong — this is a legitimate reason to call

How to assess retractions

Retractions are one of the most important signs of respiratory distress. Look for:

• Subcostal retractions: the skin below the rib cage pulls in sharply with each breath
• Intercostal retractions: the skin between the ribs pulls in
• Suprasternal retractions: the notch above the breastbone pulls in with each breath (most severe)

Any visible retractions in an infant are a sign they are working too hard to breathe.

Pulse oximetry at home

A pulse oximeter gives you a concrete number. In healthy infants, SpO₂ is typically 97–100%. In RSV:

• 95–97%: Watch closely. Call your pediatrician if it's not recovering.
• 90–94%: Call your pediatrician now. Consider going to the ER.
• Below 90%: Go to the ER or call 911.

Note: readings can be inaccurate if the baby is moving, cold hands are affecting circulation, or the clip is not properly positioned. Take multiple readings before acting on a single number.

Pulse oximeters on Amazon →

What happens at the ER

If your baby is admitted for RSV, treatment is mainly supportive — there is no antiviral medication approved for RSV in infants. Treatment typically includes:

• Supplemental oxygen via nasal cannula or mask
• IV or nasogastric fluids for hydration
• Suctioning of nasal secretions
• Monitoring of oxygen levels and breathing rate
• High-flow nasal cannula (HFNC) for moderate-to-severe respiratory distress
• In severe cases: mechanical ventilation

Most infants hospitalized for RSV recover well. The hospitalization is to provide support while the virus runs its course.

Not medical advice. Always consult your pediatrician. In an emergency, call 911.