IOPAMIDOL-370
Clinical safety rating: caution
Comprehensive clinical and safety monograph for IOPAMIDOL-370 (IOPAMIDOL-370).
Iopamidol is a nonionic, water-soluble, iodinated radiographic contrast agent that attenuates X-rays, thereby enhancing vascular and tissue contrast during imaging procedures. Its mechanism is physical rather than pharmacological, based on iodine content and osmolality.
| Metabolism | Iopamidol is not metabolized; it is excreted unchanged by glomerular filtration with a half-life of approximately 2 hours (normal renal function). |
| Excretion | Primarily renal; >90% of administered dose excreted unchanged in urine via glomerular filtration within 24-48 hours. Less than 1% excreted in feces or bile. |
| Half-life | Terminal elimination half-life is approximately 2 hours (range 1.5-2.5 hours) in patients with normal renal function. Prolonged to 10-70 hours in patients with renal impairment, necessitating dose adjustment or avoidance. |
| Protein binding | Negligible; less than 1% bound to plasma proteins (primarily albumin). |
| Volume of Distribution | Mean Vd is approximately 0.26-0.36 L/kg, indicating distribution primarily in extracellular fluid. Total body water distribution is not achieved. |
| Bioavailability | 100% bioavailability after intravascular administration; oral bioavailability is negligible (<1%) due to poor gastrointestinal absorption. |
| Onset of Action | Immediate upon intravascular injection; enhancement of vascular structures seen within seconds. For intrathecal use, onset is within minutes after injection. |
| Duration of Action | Duration of diagnostic enhancement is approximately 30-60 minutes for intravascular studies; peak enhancement occurs 1-2 minutes post-injection. Rapid redistribution and elimination limit prolonged contrast effect. |
1-2 mL/kg (370 mg iodine/mL) IV up to a maximum of 150 mL per procedure for contrast-enhanced CT; for angiography, dose varies by procedure.
| Dosage form | INJECTABLE |
| Renal impairment | In patients with GFR <30 mL/min/1.73m2, use lowest necessary dose, consider alternative imaging; for GFR 30-59, ensure adequate hydration and limit dose to <1 mL/kg; no specific dose reduction for mild impairment (GFR ≥60). |
| Liver impairment | No dose adjustment required for Child-Pugh A or B; Child-Pugh C: use with caution and lowest possible dose due to increased risk of nephrotoxicity, but no specific dose modification. |
| Pediatric use | 0.5-2 mL/kg IV up to a maximum of 3 mL/kg per procedure (not to exceed 100 mL total) for contrast-enhanced CT; adjust based on weight and clinical indication. |
| Geriatric use | No specific dose adjustment, but consider age-related renal decline; assess renal function (eGFR) before administration, reduce dose and ensure hydration; use lowest necessary dose. |
| 1st trimester | Consult provider |
| 2nd trimester | Consult provider |
| 3rd trimester | Consult provider |
Clinical note
Comprehensive clinical and safety monograph for IOPAMIDOL-370 (IOPAMIDOL-370).
| Breastfeeding | Limited excretion into breast milk; estimated infant dose <0.1% of maternal dose. M/P ratio not established. American College of Radiology advises no need to interrupt breastfeeding after iopamidol administration; mother can resume breastfeeding normally. |
| Teratogenic Risk | Iopamidol-370, as an iodinated contrast agent, crosses the placenta. First trimester exposure: theoretical risk of fetal hypothyroidism, but human data limited; considered low risk with single diagnostic dose. Second and third trimesters: neonatal hypothyroidism possible due to free iodide; transient and typically reversible. No evidence of teratogenicity in animal studies. Overall, benefit of indicated imaging outweighs risk. |
■ FDA Black Box Warning
Risk of severe, life-threatening adverse reactions including anaphylactic shock, cardiac arrest, hemodynamic instability, and seizures, particularly with intrathecal use.
| Serious Effects |
["History of hypersensitivity reaction to iopamidol or other iodinated contrast agents.","Severe renal impairment (eGFR <30 mL/min/1.73 m²) unless dialysis is planned.","Anuria or oliguria.","Acute pancreatitis (relative)."]
| Precautions | ["Risk of contrast-induced nephropathy, especially in patients with pre-existing renal impairment, diabetes, or dehydration.","Serious anaphylactoid reactions; require emergency resuscitation equipment.","Thyroid storm in patients with hyperthyroidism.","Intrathecal administration may cause arachnoiditis, seizures, or neurological deficits.","Extravasation risk leading to tissue necrosis.","Sickle cell disease: risk of sickling with hypertonic agents."] |
Loading safety data…
| Fetal Monitoring | Monitor maternal renal function prior to administration due to risk of contrast-induced nephropathy. In pregnancy, assess fetal heart rate and uterine activity during procedure if feasible. Post-procedure, check neonatal thyroid function (TSH, free T4) at birth and 1-2 weeks if significant exposure occurred, especially in preterm infants. |
| Fertility Effects | No known adverse effects on human fertility. Animal studies show no impaired fertility at clinically relevant doses. Iopamidol is not gonadotoxic. |