<prompt> Radiocontrast is contraindicated in all except-Renal failurePatient on metforminDehydrationObesity  <response>: Ans. is d i.e., Obesity o Renal failure and dehydration are risk factors for contrast induced nephropathy.Metformin causes increase risk of developing contrast induced nephropathy and subsequent lactic acidosis ___Genitourinary radiologyAdverse reactions to radiocontrast agentso Two important reactions to radiocontrast agents are : -Acute non-renal adverse reaction These may be of two types : -AllergicAnaphylactic : Non IgE mediated anaphylactic reaction e.g., Tachycardia with hypotension, urticaria, and bronchospasm.Vasomotorvasovagal reaction : e.g.. Bradycardia.Renal reaction : Contrast induced nephropathy : - Contrast media are excreted by Kidney and contrast media can precipitate renal failure. The risk factors for contrast induced nephropathy are Renal insufficiency Nephrotic syndrome Transplanted kidney Diabetes Concomitant hypotension Hyperuricemia Old age Medications NSAIDs, aminoglycoside Proteinuria Dehydration Hypertension Anemia Patient on metformin 