The common cold is a mild upper respiratory infection caused by a virus, and it is an extremely frequent occurrence in infancy. Babies have immature immune systems and are still developing protection against the hundreds of viruses that cause colds. It is normal for infants to experience anywhere from six to ten colds during their first year of life, especially if they are in a childcare setting or have older siblings. This common illness is generally self-limiting, meaning it will resolve on its own as the body fights off the infection.
The Typical Timeline of a Baby Cold
A common cold in a baby typically runs its course in seven to ten days, though specific symptoms may linger longer. The initial phase, beginning one to three days after exposure, often includes a runny nose that is usually clear and watery, sneezing, and possibly a mild fever. Symptoms will peak around day three to five, which is often the most difficult period for the baby.
During the peak, the nasal discharge often thickens and may change color, appearing yellow or green. This color change is a normal sign that the baby’s immune system is actively fighting the virus. A cough may also become more pronounced at this stage, sometimes worsening at night as mucus drains into the throat. Resolution begins after the peak, with symptoms gradually improving over the next few days.
A residual cough or some nasal congestion can persist for up to 10 to 14 days after the main illness has passed, and occasionally a mild cough may last as long as three weeks. The baby is most contagious in the day or two before symptoms appear and during the initial days when the nose is very runny.
Managing Symptoms With Home Comfort Measures
Since a baby’s cold is a viral infection, treatment focuses on comforting the infant and managing symptoms. A primary concern is nasal congestion, which can interfere with feeding and sleep because young infants are obligatory nose breathers. Nasal saline drops or spray can be applied to moisten and loosen the thickened mucus in the nasal passages.
After using the saline, a bulb syringe or nasal aspirator is effective for gently suctioning the mucus out, particularly before feeding times. Using a cool mist humidifier in the baby’s room, especially during naps and at night, can help to thin secretions and soothe the irritated airways. Caregivers must clean the humidifier frequently according to the manufacturer’s instructions to prevent the growth of mold or bacteria.
Ensuring proper hydration is important, as fever and increased mucus production cause fluid loss. Offer extra breast milk or formula to babies. If the infant is over six months old, small amounts of water or an electrolyte solution may be offered after consulting with a pediatrician. Over-the-counter cough and cold medicines are not recommended for infants and toddlers, as they are ineffective and can cause dangerous side effects. Never give honey to a baby under one year of age, as it carries the risk of infant botulism.
Warning Signs That Require Medical Attention
A cold can sometimes lead to a more serious condition, and it is important to recognize signs that warrant immediate medical attention.
Fever Concerns
Any fever (a rectal temperature of 100.4°F or 38°C) in a baby under three months old should prompt an immediate call to the doctor to rule out a severe infection. For babies older than three months, contact a healthcare provider if a fever rises above 102°F (38.9°C) or lasts longer than two to three days.
Respiratory Distress
Seek emergency medical care if the baby shows signs of struggling to breathe, such as flaring nostrils or fast, shallow breathing. Look for retractions, which appear as the skin pulling in between the ribs, above the collarbone, or below the ribcage with each breath. Wheezing, a whistling sound while breathing, or a blue, gray, or pale color around the lips or face also requires urgent attention.
Dehydration and Behavior
Call a doctor if the baby has significantly fewer wet diapers than normal, which is a sign of dehydration. Other concerning signs include extreme lethargy, difficulty waking the baby, or a refusal to feed or drink fluids for several hours. If the cold symptoms do not improve, or if they worsen after ten to fourteen days, consult a pediatrician.