What are the side effects of Intravenous (IV) Contrast?

From the Guidelines

Intravenous (IV) contrast agents used in imaging studies can cause several side effects, and to minimize these risks, patients should be properly screened before receiving contrast, adequately hydrated before and after the procedure, and monitored for adverse reactions. Common mild side effects include a warm sensation during injection, metallic taste in the mouth, nausea, vomiting, headache, itching, and flushing. More serious side effects include allergic reactions that can range from mild hives to severe anaphylaxis with breathing difficulties and cardiovascular collapse. Contrast-induced nephropathy is another significant concern, particularly in patients with pre-existing kidney disease, diabetes, dehydration, or those taking nephrotoxic medications.

Key Considerations

• Patients with a history of contrast reactions may benefit from premedication with antihistamines and corticosteroids 1.
• The use of alternative imaging methods or lower doses of contrast may be considered when possible, especially for those with kidney concerns 1.
• IV volume expansion with either isotonic sodium chloride or sodium bicarbonate solutions is recommended for patients at increased risk of contrast-induced acute kidney injury (CI-AKI) 1.
• The lowest possible dose of contrast medium should be used in patients at risk for CI-AKI 1.

Recent Guidelines and Recommendations

• The European Medicines Agency's Pharmacovigilance and Risk Assessment Committee recommended suspension of the marketing authorization for 4 linear gadolinium contrast agents due to convincing evidence of gadolinium deposition in the brain months after injection 1.
• Key experts in the field recommend a shift in clinical practice from linear to macrocyclic agents, except where there is no suitable alternative 1.

Patient Education and Monitoring

• Patients should inform healthcare providers immediately if they experience symptoms like difficulty breathing, chest pain, severe dizziness, or swelling after receiving contrast.
• Patients should be monitored for adverse reactions, and those with kidney concerns should be closely evaluated for the risk of CI-AKI.

Overall, the management of IV contrast agents requires careful consideration of the potential risks and benefits, as well as adherence to recent guidelines and recommendations to minimize adverse effects.

From the Research

Intravenous Contrast Side Effects

• Adverse events after administration of contrast are low, but clinicians and radiologists must minimize risks and respond quickly to reactions 2
• Adverse reactions to intravenous iodinated contrast media can be classified as general and organ-specific, such as contrast-induced nephrotoxicity 3
• Non-ionic contrast media have a lower risk of mild and moderate adverse reactions, but the risk of fatal reactions is similar for ionic and non-ionic contrast media 3

Risk Factors and Prevention

• Patients with pre-existing renal insufficiency, diabetes mellitus, and congestive heart failure are at highest risk for nephropathy induced by contrast media 4
• Risk factors also include the type and amount of contrast medium administered 4
• Corticosteroid premedication can be effective in preventing recurrence of acute allergic-like reactions to low osmolar contrast media in high-risk patients 5
• Patients with severe index reactions are still at risk of developing severe reactions despite corticosteroid premedication 5

Contrast-Induced Nephropathy

• Contrast-induced nephropathy (CIN) has been observed in both experimental and clinical studies, but recent observational studies have questioned its prevalence and severity 6
• Patients with estimated glomerular filtration rates (eGFRs) ≥ 45mL/min/1.73m2 are at negligible risk for CIN, while patients with eGFRs < 30mL/min/1.73m2 are at high risk for CIN 6
• Patients with eGFRs between 30 and 44mL/min/1.73m2 are at an intermediate risk for CIN, unless diabetes mellitus is present, which would further increase the risk 6