Benefits of Immunocal. Immunotech warns that people with an allergy to milk proteins and those undergoing immunosuppresive therapy should not use Immunocal. People following a protein-restricted diet will need to calculate the 9 g of protein provided by each pouch of Immunocal. Abdominal cramps and bloating are occasional side effects and a rash is possible, but rare. If a rash occurs, discontinue use of the product immediately. Large doses, exceeding 7 g, of cysteine can be toxic.