Ans. CSide effects of iodinated contrast material are:Idiosyncratic - Anaphylactoid reaction. They are complement-mediated reactions and not IgE. The patient develops bronchospasm and hypotension.Dose-dependent side effect - Contrast-induced nephropathy and seen especially with high osmolar agents.Contrast-induced nephropathy:The patient has non-oliguric transient nephropathy and occurs due to tubular damage. It is defined as the impairment of renal function and is measured as either a 25% increase in serum creatinine from baseline or 0.5 mg/dl increase in absolute value, within 48-72hrs of intravenous contrast administration.Risk Factors for Contrast Medium-Induced Nephropathy:Patient-related:eGFR < 60 mL/min/1.73 m2 before intra-aerial administrationeGFR < 45 mL/min/1.73 m2 before intravenous administrationIn paicular in combination with:Diabetic nephropathyDehydrationCongestive hea failure (NYHA grade 3-4) and low LVEFRecent myocardial infarction (Intra-aoic balloon pumpPeri-procedural hypotensionLow hematocrit levelAge over 70Concurrent administration of nephrotoxic drugsKnown or suspected acute renal failureProcedure-related:Intra-aerial administration of contrast mediumHigh-osmolality agentsLarge doses of contrast mediumMultiple contrast medium administrations within a few daysIf the patient is on Metformin and is having de-arranged RFT, then before giving contrast agent metformin should be stopped since it can precipitate lactic acidosis