Side effects such as chills, headache, dizziness, fever, vomiting, allergic reactions, nausea, arthralgia (joint pain), low blood pressure and moderate low back pain may occasionally occur with Flebogamma DIF. Rarely human normal immunoglobulins may cause a sudden fall in blood pressure and, in a few cases, anaphylactic shock (a severe allergic reaction) even when the patient had no previous allergic reaction to the medicine.

Flebogamma DIF must not be used in people who are allergic to normal human immunoglobulin or any of the other ingredients, or in patients who are allergic to other types of immunoglobulin, especially where they have deficiency (very low levels) of immunoglobulin A (IgA) and they have antibodies against IgA. The medicine must not be used in patients who are intolerant to fructose (a type of sugar). In babies and young children, hereditary fructose intolerance may not yet have been diagnosed and may be fatal; this medicine must therefore not be given to babies and children below two years of age.