Medical Complications Associated With Chronic IVIG Use

Intravenous immunoglobulin (IVIG) treatment is generally considered a safe treatment option for certain neurological disorders, however, it is not without risks nor is it necessarily the most effective option.

Mild infusion-related side effects are common and experienced by 5–20% of patients during or shortly after infusion. These are usually self-limited. However, intravenous immunoglobulin therapy can also cause more serious adverse effects in some patients, such as thromboembolism.

IVIG can increase blood viscosity and has been associated with an increased risk of blood clots, including deep vein thrombosis, stroke, and myocardial infarction, particularly in older adults or those with pre-existing cardiovascular risk factors. Thrombotic events have been reported even at standard doses, so patients with risk factors such as advanced age, hypercoagulable states, diabetes mellitus, or prolonged immobilization should be monitored closely during and after infusion. Another important risk is acute kidney injury, which has been well documented in clinical studies (Justiz-Vaillant et al., 2023).

Intravenous immunoglobulin (IVIG) is a key therapy in the treatment of several neurologic disorders, including chronic inflammatory demyelinating polyneuropathy (CIDP), multifocal motor neuropathy (MMN), and myasthenia gravis (MG). Still, chronic IVIG therapy deserves careful consideration, particularly in the context of underlying conditions.

As a neuro health clinic, we understand that many patients rely on IVIG for chronic neurological conditions, but people want to know what complications can occur, how often they appear, and what steps can reduce risk. This overview brings together the current evidence to help patients and families gain a better understanding.

What Are the Most Common Complications? Common Adverse Effects of IVIG

Most individuals experience minor adverse effects during or after an immunoglobulin infusion. These include fatigue, low-grade fever, flushing, nausea, or a persistent headache that worsens with a rapid infusion rate or dehydration. These minor symptoms usually resolve with rest, hydration, and simple analgesics. While these reactions can be uncomfortable, they rarely interrupt ongoing IVIG therapy.

The risks of more serious adverse effects remain low in absolute terms but become more relevant with chronic therapy, complex comorbidities, or rapid infusion rates.

Thromboembolic Complications

IVIG can increase serum viscosity, especially in older patients, those with vascular disease, or when high doses are given over a short period. Studies in neurologic disease populations have reported events such as pulmonary embolism, myocardial infarction, and deep venous thrombosis. A large observational study of patients with inflammatory neuropathies receiving maintenance IVIG found clinically significant clotting events over the course of long-term therapy (Kapoor et al., 2020).

Renal Impairment

While uncommon, acute renal failure can occur in patients who already have renal vulnerability, such as older adults, patients with diabetes mellitus, or those taking nephrotoxic medications. Renal impairment can develop within hours to days after an IVIG infusion, especially with certain stabilizing agents used in older formulations. Modern preparations have reduced the risk of these severe adverse reactions, but it remains present.

Infusion-Related & Delayed Adverse Reactions

These can include aseptic meningitis, severe headaches, or neurologic symptoms appearing one to two days after infusion. Although rare, cases of acute respiratory distress, hemolysis, and hypotension have been reported in the literature.

Long-Term Effects of IVIG

Over time, patients may experience cumulative issues such as fluid retention, fluctuations in blood pressure, or repeated episodes of infusion-related malaise. Accessible peripheral veins for IV access may become, with time, more rare and require the installation of a port-a-cath. For many with chronic neurologic disease, long-term IVIG therapy becomes routine, but it requires continuous assessment.

Clinical Trial Options for MG Patients

Some individuals with myasthenia gravis eventually reach a point where long-term IVIG therapy becomes harder to sustain or no longer provides the level of stability it once did. When this happens, it makes sense to look at newer targeted treatments, including those currently being evaluated in research settings. At Neuro Outaouais, our team is participating in a clinical trial examining Efgartigimod (Vivgart) for AChR-antibody–positive generalized Myasthenia Gravis. The study compares Efgartigimod with IVIG to better understand how the two differ in symptom control, durability of benefit, and long-term safety.

More information is available through our page on myasthenia gravis research. If you’re living with MG and want to know whether this study or other emerging options might be suitable for you, we encourage you to contact our team to learn more.