Field Guide · Treatment × Condition
When a child’s own antibodies are inflaming their brain — whether the trigger was a tick-borne infection or another driver — one of the most powerful tools to calm that attack is IVIG. Here is what it is, how it works on an immune-mediated encephalitis, who it’s considered for, and the hard realities of qualifying and getting it covered.
I walked this part of the labyrinth myself — knocked on the doors, read the research, and came back with the map. You don’t have to find the way out alone.
IVIG — intravenous immunoglobulin — is concentrated antibodies pooled from thousands of healthy donors, given as an infusion. In autoimmune encephalitis, where the immune system makes antibodies that attack the brain, IVIG acts as an immune modulator: it can dilute and neutralize the harmful antibodies, dampen the inflammatory attack, and help reset the immune response. It’s an established treatment for several forms of autoimmune encephalitis, and it’s used in the more severe, immune-driven end of the PANS spectrum.
The key insight is that, in these conditions, the brain inflammation is being driven by the immune system itself — specifically by antibodies that have started attacking brain tissue. The infection or other trigger may have lit the fuse, but the ongoing fire is autoimmune.
IVIG works on exactly that fire. By flooding the system with a huge, diverse pool of healthy antibodies, it can crowd out and neutralize the harmful ones, soak up inflammatory signals, and nudge the immune system back toward balance. That is why it can help even when antibiotics or antivirals alone don’t fully resolve the picture — it addresses the immune response, not just the original bug.
When a tick-borne infection has set off an antibody-mediated attack on the brain, the inflammation isn’t only about the organism anymore — the immune system has turned on the child. In that situation IVIG may be considered to calm the immune-mediated inflammation, generally alongside treating the underlying infection. The principle is to do both at once: remove what lit the fire (the infection) and calm the fire (the autoimmune attack). Doing only one tends to leave the other smoldering. This is specialist territory, and sequencing matters.
IVIG is a serious intervention — an infusion with real costs and real side effects — so it’s reserved for cases where the immune-mediated picture is clear:
In the PANS consensus literature, immunomodulatory therapies including IVIG are positioned for the moderate-to-severe end of the spectrum, after or alongside treating triggers, rather than as a first step for every child.
Coverage is often the hardest part of all. IVIG is expensive, and insurers frequently deny it for PANS-spectrum and Lyme-associated diagnoses. Approval usually demands extensive documentation: a clear diagnosis, demonstrated severity and impairment, evidence that prior treatments failed, and often one or more rounds of appeals.
Many families only succeed after appealing — with a knowledgeable specialist building the case carefully. That’s why preparation and documentation matter so much: the medicine may be appropriate and still take a fight to obtain. Going in knowing that is half the battle.
The full IVIG entry — who qualifies, the studies, and the insurance fight in detail ›
Is your child’s case an immune-mediated one? Plan B reads the history, symptoms, and labs together, helps you understand whether the picture points toward an autoimmune mechanism, and turns it into a clear plan and the documentation to bring to a specialist. Your first Synthesis is free.
Start your free Synthesis → Parent education, not medical advice. You stay in charge.When a child’s own antibodies are attacking their brain, IVIG can calm an immune-mediated encephalitis — an established tool for the more severe, autoimmune end of the picture, including cases where a tick-borne infection lit the fuse. Used well, it’s paired with treating the underlying trigger: remove what lit the fire and calm the fire. The medicine can be the right call and still take documentation and appeals to obtain, so go in prepared. This is parent education, not medical advice — bring it to your team as questions.
Plan B does not partner with drug companies or doctors, and we never endorse anyone whose healing isn’t verified by families. We show you the options and how to vet them yourself — and we’re building parent verification: look up a practitioner and see real family reviews before you trust them. Universal bad reviews? Skip.