Patients receiving human normal Ig for the 1st time, high rate of infusion, hypo- or agammaglobulinaemia w/ or w/o IgA deficiency, overwt, diabetes, HTN, hypovolaemia, vascular diseases, hereditary or acquired thrombotic disorder, thrombotic episodes, disease causing viscous blood, renal impairment. May impair ability to drive or operate machinery. Elderly ≥65 yr. Pregnancy & lactation.