You did not say how old your baby is now. If he is allergic to milk, he should not eat any milk, cheese, pudding or ice cream. Perhaps you can find soy ice cream and soy cheese in the grocery store.
Usually, infants are allergic to the protein casein in milk. I cannot predict whether your baby will or will not ever tolerate milk products. Have you asked your baby’s doctor? Perhaps he can re-test your son in a medical environment where he can treat any sudden breathing or swallowing problems your son may have in reaction to a milk test. You should not test your son at home to even small quantities of milk products as it may cause breathing or swallowing problems.
In the meantime, though, keep your baby on soy formula until 12 months of age or soymilk after 12 months of age. There are several infant formulas, such as Isomil, Prosobee, Pregestimil or Nutramigen that you could substitute for fluid milk. Otherwise, discuss a calcium supplement with your baby’s doctor. Milk is the most important food in the diet of an infant or child. It is a major source of complete protein, calcium, phosphorus, riboflavin, vitamin A and vitamin D, water and calories.
Symptoms of milk allergy are abdominal cramping, vomiting or watery diarrhea that occur within a few minutes to a few hours after eating a milk product. Milk protein allergy can cause hives (red bumps on the skin) or itchy skin rash in or around the mouth, coughing, runny nose, watery eyes, wheezing or interfering with breathing or swelling in the throat preventing normal swallowing. It can also cause colic in babies.