A number of infants who cannot tolerate cows' milk may also be intolerant to soya protein and may require an alternative formula containing a specially processed form of protein, such as hydrolysed whey protein. These formulas, often called 'hypoallergenic infant formulas' are recommended for use under medical supervision only.

Other specialised infant formulas are available for babies who have very special needs, such as premature babies or babies with metabolic or other disorders. These products differ in composition from formulas for healthy infants and are used under medical supervision only.