Current dosing of IVIg for neurological disorders has been extrapolated from earlier studies with small numbers of patients. A study of immunomodulation with IVIg described seven paediatric patients with idiopathic thrombocytopenic purpura . The patients received an initial dose of 0·4 g/kg for 5 consecutive days, followed by maintenance therapy of 0·4 g/kg every 1–6 weeks. Two small-scale trials published in 1984 demonstrated that IVIg treatment was effective in myasthenia gravis (MG) patients at
doses of six infusions of 20 g for 2 weeks  or 1–2 g/kg for 5 days . In nine CIDP patients initial treatment was with 0·4 g/kg/day for 5 consecutive days . Thereafter, the patients were treated with the lowest effective dose at the longest selleck chemicals llc possible intervals.
This study may represent one of the first attempts at optimizing IVIg therapy. Current practice is to use a broad range of dosages for these chronic neurological conditions. Selleck C59 wnt The same is true in primary immunodeficiencies in terms of the wide variations in dosage, treatment interval and target trough levels, as demonstrated in a 2012 survey of immunologists . The selection of appropriate IVIg dose and dosing interval has far wider implications, including the impact on economic considerations (including the cost of IVIg), the limited supply of Ig, convenience to the patient, possible adverse effects and, of course, optimizing maintenance therapy in order to prevent long-term disability in these patients. Although most neurologists will treat with initiation therapy, typically
0·4 g/kg for 5 days, followed by maintenance therapy of 1–2 g/kg/month, other therapeutic regimens have been utilized in different neurological disorders. A study in 2005 compared Non-specific serine/threonine protein kinase 1 g/kg with 2 g/kg dosing in MG patients, and found no significant difference between the two doses for the primary and secondary end-points . A similar study in Guillain-Barré syndrome (GBS) patients compared 0·4 g/kg/day for 3 days versus the same dose for 6 days, and found no significant difference between the two regimens on time to walking with assistance ; however, there was a significant difference between the two groups when studying the subset of patients on mechanical ventilation, indicating that variable dosing may be of benefit for patients with more severe disease. Guidelines have been published to review indications for neurological disorders , and in 2010 the European Federation of Neurological Societies published guidelines for the management of CIDP and multifocal motor neuropathy (MMN), respectively, which suggest individualized assessment and treatment with IVIg [10, 11]. When contemplating the appropriate use of a limited resource, a convenient solution is to consider reducing the IVIg dose or discontinuing treatment if the patient no longer requires it, or if treatment is ineffective.