Infant Vomiting

Dear Lisa,

My son is three months old and has been vomiting for 3 days. He also has a knot on his back about the size of an eraser that has been there for 2 months. Any ideas as to why?

“Vomiting for 3 days”

Dear “Vomiting for 3 days”,

Infants can vomit for a variety of reasons. A healthy infant with no medical conditions may vomit if they eat too much or if they are jostled around too much after a feeding. Conditions that cause increased intra-abdominal pressure, such as burping may also cause an infant to vomit. Around 3 months old, infants start putting their hands in their mouth which can accidentally elicit their gag reflex and cause vomiting. Or vomiting can occur after the introduction of a new food and represent a food sensitivity. Typically in each of these scenarios the vomit should look like milk and the child should appear well.

If a baby is not irritable, free from a temperature, gaining weight normally, eating well, stooling on a regular basis and not experiencing a distended abdomen then there is no need for concern. If an infant’s vomiting is accompanied by diarrhea, fever, irritability, a distended abdomen, constipation, foul smelling urine, insufficient weight gain, feeding difficulties or cough he should be seen by his Doctor or Nurse Practitioner. Other signs that an infant’s vomiting may be due to a medical condition include projectile vomiting, (vomit shoots out of the mouth a few feet) or bilious vomiting. Bilious vomiting appears thick and yellowish green in color. Both of these symptoms need to be seen by a health care professional.

Babies with Gastroesophageal reflux (GER) may also present with vomiting. Signs of gastroesophageal reflux include excessive hiccoughing, back arching, vomiting with feedings, Sandifer’s syndrome (repetitive stretching and arching of the head and neck), irritability with feeding, cough, wheezing, nasal congestion or sometimes apnea. (1,2) Typically infants have increase symptoms of GER if they are not elevated after a feeding, if they move too much after a feeding, if they have an upper respiratory infection or if they are allergic to their formula.(3) If you notice that your son has signs of GER contact his Pediatrician for an evaluation.

In regards to your question about the knot on your baby’s back that is the size of an eraser, that needs to be evaluated by your son’s Doctor. Skin lesions or moles may be related to a medical condition depending on their appearance and location. This determination can only be made after a complete history and physical examination of your baby by a health care professional. A cyst like mass, skin lesion or mole close to the spine or above the crack of a child’s buttock may be a sign of an underlying neurological condition such as Spina Bifida Occulta or tethered cord. On the other hand a rubbery subcutaneous (under the skin) mobile, non-tender, skin colored mass at the nape of a baby’s neck may be a lymph node. Babies tend to develop enlargement of lymph nodes at the base of their neck when they have eczema on the face or scalp, a scratch on their head or cradle cap.

It is important to bring your child to the Pediatrician for his routine well child examinations so that his symptoms of vomiting can be monitored and his weight gain can be tracked.


(1)Rudolph CD, Mazur U, Liptak GS. North American Society for Pediatric Gastroenterology and Nutrition. Guidelines for evaluation and treatment of Gastroesophageal reflux in infants and children: Recommendations of the North American Society of Pediatric Gastroenterology and Nutrition. J Pediatr Gastroenterol Nutr. 2001;32(suppl 2):S1-31.
(2)Suwandhi E, Ton M, Schwarz S. Gastroesophageal Reflux in Infancy and Childhood. Pediatric Annals. 2006;(35)4:259-266.
(3)Poets CF. Gastroesophageal Reflux. A critical review of its role in preterm infants. Pediatrics. 2004;113:128-132.


Lisa-ann Kelly R.N., P.N.P.,C.
Certified Pediatric Nurse Practitioner

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