Intravenous immunoglobulin (IVIG) has 6 FDA approved indications and is prescribed off-label for many others. How many of these uses are justified is controversial.

Some patients with primary immune deficiency are injected with intravenous immune globulin (IVIG) every 3-4 weeks. Now a subcutaneous immune globulin (SCIG) has also been approved in the US for this indication (Vivaglobin - CSL Behring). SCIG has been used in Europe for about 10 years.

Intravenous formulations of immune globulin (IVIG) have been available for more than ten years for treatment of immune deficiency (Medical Letter, 24:81, 1982). Seven preparations are now licensed in the USA, with additional indications for their use.

The gram-positive anaerobic bacillus Clostridium difficile is the most common identifiable cause of antibiotic-associated diarrhea. The antibiotics most often implicated have been ampicillin, second and third generation cephalosporins, clindamycin and fluoroquinolones. The emergence in recent years of a new, more toxic epidemic strain (BI/NAP1), possibly related to widespread use of fluoroquinolones, has caused a marked increase in the incidence and severity of C. difficile-associated disease (CDAD).

The FDA has approved fostamatinib disodium hexahydrate (Tavalisse – Rigel), the first spleen tyrosine kinase (SYK) inhibitor, for oral treatment of thrombocytopenia in adults with chronic immune thrombocytopenia (ITP) who have had an insufficient response to a previous treatment.

immune globulin (human) has been available for many years in an intramuscular (IM) formulation for prevention of Rh isoimmunization in pregnant Rh-negative women (Medical Letter, 16:3, 1974). Recently, the US Food and Drug Administration (FDA) approved the first intravenous (IV) immune globulin preparation (WinRho SD - Univax), not only for preventing Rh isoimmunization, but also for treatment of immune thrombocytopenic purpura (ITP) in Rh-positive patients.

The US manufacturer of varicella zoster immune globulin (VZIG; Massachusetts Public Health Biologic Laboratories, Boston, MA) recently discontinued its production. A Canadian formulation, VariZIG (Varicella Zoster Immune Globulin [Human] - Cangene Corporation, Winnipeg) is now available in the US under an investigational new drug application expanded access protocol.

The FDA has approved an extended-release formulation of minocycline (Solodyn - Medicis) for once-daily treatment of non-nodular moderate to severe acne.

Posaconazole (Noxafil - Schering-Plough), an oral azole antifungal with a chemical structure similar to that of itraconazole (Sporanox), has been approved by the FDA to prevent Candida and Aspergillus infections in severely immunocompromised patients and for treatment of oropharyngeal candidiasis. It is likely also to be used off-label for treatment of other fungal infections, including those caused by Mucor and other Zygomycetes.

Clostridium difficile infection (CDI) is the most common infectious cause of healthcare-associated diarrhea in adults. The incidence and severity of CDI have increased in recent years with the emergence of an epidemic virulent strain (NAP1/BI/027). Common risk factors include admission to a healthcare facility, increasing age and severity of underlying illness, gastric acid suppression and exposure to antimicrobials, particularly clindamycin, ampicillin, cephalosporins or fluoroquinolones. Patients who develop CDI while receiving a precipitating antibiotic should have the antibiotic...