Soy formula can make stools harder, worsening or causing constipation in some babies, according to Heyman. Another problem with switching to a soy formula: Some babies may be allergic to soy. Giving these babies soy formula could actually cause digestive problems, including constipation. According to Dr.

Does isomil cause constipation in infants?

Isomil is a soy based formula and is usually prescribed for babies with allergies or intolerances. If your baby does not pass a stool every day this does not mean she is constipated. Constipation in a small baby only occurs when the baby produces small, hard stools and has to strain to pass them.

Is soy formula more constipating?

Some soy- and cow's milk-based formulas cause harder bowel movements, while formulas that contain partially or completely hydrolyzed milk proteins (sometimes known as "hypoallergenic" formulas), which may be recommended for infants with an allergy or sensitivity to cow's milk, can cause loose bowel movements.