Iohexol
Injection, Solution · Intra-articular, Intrathecal, Intravascular
Uses
Iohexol is a radiographic contrast agent indicated for intrathecal, intra-arterial, intravenous, oral, rectal, intraarticular and body cavity imaging procedures in adults and pediatric patients. ( 1 ) 1.1 Intrathecal Procedures ‡ Iohexol injection is indicated for: Myelography and computerized tomography (CT) myelography (lumbar, thoracic, cervical, total columnar) in adults and pediatric patients aged 2 weeks and older CT cisternography in adults and pediatric patients aged 2 weeks and older 1.2 Intra-arterial Procedures ‡ Iohexol injection is indicated for: Cardiac ventriculography in adults and pediatric patients Aortography including studies of aorta and its branches in adults and pediatric patients Selective coronary arteriography in adults Cerebral arteriography in adults Peripheral arteriography in adults Intra-arterial digital subtraction angiography (IA-DSA) of the head, neck, abdominal, renal and peripheral vessels in adults Pulmonary angiography in pediatric patients 1.3 Intravenous Procedures ‡ Iohexol injection is indicated for: Excretory urography in adults and pediatric patients CT of the head and body in adults and pediatric patients Peripheral venography (phlebography) in adults Intravenous digital subtraction angiography (IV-DSA) of the head, neck, abdominal, renal and peripheral vessels in adults 1.4 Oral or Rectal Procedures ‡ Iohexol injection is indicated for: Radiographic examination of the gastrointestinal (GI) tract in adults and pediatric patients CT of the abdomen and pelvis in conjunction with intravenous administration of iohexol injection in adults and pediatric patients 1.5 Intraarticular Procedures ‡ Iohexol injection is indicated for: Arthrography in adults 1.6 Body Cavity Procedures ‡ Iohexol injection is indicated for: Endoscopic retrograde pancreatography (ERP) and cholangiopancreatography (ERCP) in adults Herniography in adults Hysterosalpingography in adults Voiding cystourethrography (VCU) in pediatric patients ‡ Specific dosage forms, concentrations and presentations of iohexol are recommended for each type of imaging procedure [see Dosage and Administrations (2.2 , 2.3 , 2.4 , 2.5 , 2.6 , 2.7 , 2.8 , 2.9 ) and Warnings and Precautions (5.1 , 5.2) ].
Dosage and administration
For each imaging procedure, specific dosage forms, concentrations and presentations are recommended. Individualize the concentration and volume according to the specific dosing tables and accounting for factors such as age, body weight and condition of the patient and the equipment and imaging technique used. ( 2.2 , 2.3 , 2.4 , 2.5 , 2.6 , 2.7 , 2.8 , 2.9 ) See full prescribing information for complete dosing and administration information. ( 2 ) 2.1 Important Dosage and Administration Instructions Specific dosage forms, concentrations and presentations of iohexol are recommended for each type of imaging procedure [see Dosage and Administration (2.2 , 2.3 , 2.4 , 2.5 , 2.6 , 2.7 , 2.8 , 2.9 ) and Warnings and Precautions (5.1 , 5.2) ]. Individualize the volume, strength and rate of administration of iohexol injection according to the specific dosing tables [see Dosage and Administration (2.2 , 2.3 , 2.4 , 2.5 , 2.6 , 2.7 , 2.8 , 2.9) ] . Consider factors such as age, body weight, vessel size, blood flow rate within the vessel, anticipated pathology, degree and extent of opacification required, structures or area to be examined, disease processes affecting the patient, and equipment and technique to be employed. Hydrate patients before and after administration of iohexol injection [see Warnings and Precautions (5.4) ]. Use aseptic technique for all handling and administration of iohexol injection. Administer iohexol injection at either body (37°C, 98.6°F) or room temperature (20° to 25°C, 68° to 77°F). Do not mix iohexol injection with, or inject in intravenous lines containing, other drugs or total nutritional admixtures. Parenteral drug products should be inspected visually for particulate matter and discoloration prior to administration, whenever solution and container permit. Each container of iohexol injection in single-dose container is intended for one procedure only. Discard any unused portion. 2.2 Recommended Dosage for Intrathecal Procedures in Adults The recommended doses for intrathecal procedures in adults are shown in Table 1. Administer over 1 minute to 2 minutes. If sequential or repeat examinations are required, allow at least 48 hours for clearance of the drug from the body before repeat administration; however, whenever possible, 5 days to 7 days is recommended. If CT myelography is performed, delay imaging by several hours to reduce the degree of contrast. Table 1: Recommended Concentrations and Volumes of Iohexol Injection for Intrathecal Procedures in Adults Imaging Procedure Injection Type Concentration (mg Iodine/mL) Volume to Administer Lumbar Myelography Lumbar 180 * 10 mL to 17 mL 240 * 7 mL to 12.5 mL Thoracic Myelography Lumbar Cervical 240 * 6 mL to 12.5 mL 300 * 6 mL to 10 mL Cervical Myelography Lumbar 240 * 6 mL to 12.5 mL 300 * 6 mL to 10 mL C1-2 180 * 7 mL to 10 mL 240 * 6 mL to 12.5 mL 300 * 4 mL to 10 mL Total Columnar Myelography Lumbar 240 * 6 mL to 12.5 mL 300 * 6 mL to 10 mL CT Cisternography Lumbar 180 * 10 mL to 17 mL 240 * 7 mL to 12.5 mL * Use single-dose containers. 2.3 Recommended Dosage for Intra-arterial Procedures in Adults The recommended doses for intra-arterial procedures in adults are shown in Table 2. Table 2: Recommended Concentrations and Volumes of Iohexol Injection for Intra-arterial Procedures in Adults Imaging Procedure Concentration (mg Iodine/mL) Volume to Administer per Single Injection for Selective Injection Sites Maximum Cumulative Total Dose Cardiac Ventriculography 350 * 40 mL (Range of 30 mL to 60 mL) may be combined with selective coronary arteriography 250 mL Aortography and Selective Visceral Arteriography 300 * Aorta (aortic arch, ascending aorta): 50 mL to 80 mL Abdominal aorta and its branches (celiac, mesenteric, hepatic and splenic arteries): 30 mL to 60 mL Renal arteries: 5 mL to 15 mL 290 mL 350 * 250 mL Aortic root and arch study when used alone 350 * 50 mL (Range of 20 mL to 75 mL) 250 mL Selective Coronary Arteriography 350 * 5 mL (Range of 3 mL to 14 mL) 250 mL Cerebral Arteriography 300 * Common carotid artery: 6 mL to 12 mL Internal carotid artery: 8 mL to 10 mL External carotid artery: 6 mL to 9 mL Vertebral artery: 6 mL to 10 mL 290 mL Peripheral Arteriography Aortofemoral Runoffs 300 * 30 mL to 90 mL 290 mL 350 * 20 mL to 70 mL 250 mL Selective Arteriogram 300 * 10 mL to 60 mL 290 mL 350 * 10 mL to 30 mL 250 mL IA-DSA (head, neck, abdominal, renal and peripheral vessels) 140 * Aorta: 20 mL to 45 mL at 8 mL/sec to 20 mL/sec Carotid artery: 5 mL to 10 mL at 3 mL/sec to 6 mL/sec Femoral artery: 9 mL to 20 mL at 3 mL/sec to 6 mL/sec Vertebral artery: 4 mL to 10 mL at 2 mL/sec to 8 mL/sec Renal arteries: 6 mL to 12 mL at 3 mL/sec to 6 mL/sec Other branches of aorta (includes subclavian, axillary, innominate and iliac): 8 mL to 25 mL at 3 mL/sec to 10 mL/sec 250 mL * Use single-dose containers. 2.4 Recommended Dosage for Intravenous Procedures in Adults The recommended doses for intravenous procedures in adults are shown in Table 3. Table 3: Recommended Concentrations and Volumes of Iohexol Injection for Intravenous Procedures in Adults Imaging Procedure Concentration (mg Iodine/mL) Volume to Administer Excretory Urography 300 * 0.6 mL/kg to 1.2 mL/kg body weight (maximum dose is 102 mL) 350 * CT Head 240 * 120 mL to 250 mL by infusion 300 ** 70 mL to 150 mL by rapid injection 350 ** 80 mL by rapid injection Body 300 ** 50 mL to 200 mL by rapid injection 350 ** 60 mL to 100 mL by rapid injection Peripheral Venography (phlebography) 240 * 20 mL to 150 mL per leg 300 * 40 mL to 100 mL per leg IV-DSA (head, neck, abdominal, renal and peripheral vessels) 350 * 30 mL to 50 mL at 7.5 mL/sec to 30 mL/sec using a pressure injector Frequently three or more doses may be required; the maximum cumulative total dose is 250 mL * Use single-dose containers. ** Use single-dose containers.
Dosage forms and strengths
Injection: Clear, colorless to pale yellow solution available in the following presentations: Dosage Form Concentration (mg of iodine/mL) Package Size Package Type Injection 300 50 mL, 75 mL and 100 mL Single-Dose Bottle 350 50 mL, 75 mL and 100 mL Injection: 300 mg iodine/mL and 350 mg iodine/mL in single-dose bottles. ( 3 )
Contraindications
Iohexol for hysterosalpingography is contraindicated during pregnancy or suspected pregnancy, menstruation or when menstruation is imminent, within 6 months after termination of pregnancy, within 30 days after conization or curettage, when signs of infection are present in any portion of the genital tract including the external genitalia and when reproductive tract neoplasia is known or suspected because of the risk of peritoneal spread of neoplasm. Hysterosalpingography during pregnancy (or suspected pregnancy), menstruation (or when menstruation is imminent), within 6 months after termination of pregnancy, within 30 days after conization or curettage, when signs of infection are present in any portion of the genital tract, including the external genitalia and when reproductive tract neoplasia is known or suspected. ( 4 )
Warnings and precautions
Hypersensitivity Reactions: Life-threatening or fatal reactions can occur. Always have emergency equipment and trained personnel available. ( 5.3 ) Acute Kidney Injury: Acute injury including renal failure can occur. Minimize dose and maintain adequate hydration to minimize risk. ( 5.4 ) Cardiovascular Adverse Reactions: Hemodynamic disturbances including shock and cardiac arrest may occur during or after administration. ( 5.5 ) Thyroid Dysfunction in Pediatric Patients 0 to 3 Years of Age: Individualize thyroid function monitoring based on risk factors such as prematurity. ( 5.9 ) 5.1 Risks Associated with Intrathecal Administration of Iohexol Injection 140 mg Iodine/mL and 350 mg Iodine/mL Use only the iodine concentrations and presentations recommended for intrathecal procedures [see Dosage and Administration (2.2 , 2.8) ]. Intrathecal administration of iohexol injection of a wrong iodine concentration, even if inadvertent, can cause death, convulsions, seizures, cerebral hemorrhage, coma, paralysis, arachnoiditis, acute renal failure, cardiac arrest, rhabdomyolysis, hyperthermia and brain edema. 5.2 Risks Associated with Parenteral Administration of Iohexol Oral Solution Adverse reactions such as hemolysis may occur if iohexol oral solution is administered intravenously or intraarterially due to low osmolality [see Description (11) ] . Iohexol oral solution is for oral use only. 5.3 Hypersensitivity Reactions Iohexol can cause life-threatening or fatal hypersensitivity reactions including anaphylaxis. Manifestations include respiratory arrest, laryngospasm, bronchospasm, angioedema and shock. Most severe reactions develop shortly after the start of the injection (within 1 to 3 minutes), but delayed reactions can also occur. There is an increased risk in patients with a history of a previous reaction to contrast agent and known allergic disorders (i.e., bronchial asthma, drug, or food allergies) or other hypersensitivities. Premedication with antihistamines or corticosteroids does not prevent serious life-threatening reactions but may reduce both their incidence and severity. Obtain a history of allergy, hypersensitivity, or hypersensitivity reactions to iodinated contrast agents and always have emergency resuscitation equipment and trained personnel available prior to iohexol injection administration. Monitor all patients for hypersensitivity reactions. 5.4 Acute Kidney Injury Acute kidney injury, including renal failure, may occur after parenteral administration of iohexol injection. Risk factors include: pre-existing renal impairment, dehydration, diabetes mellitus, congestive heart failure, advanced vascular disease, elderly age, concomitant use of nephrotoxic or diuretic medications, multiple myeloma/paraproteinaceous diseases, repetitive and/or large doses of an iodinated contrast agent. Use the lowest necessary dose of iohexol in patients with renal impairment. Adequately hydrate patients prior to and following parenteral administration of iohexol injection. Do not use laxatives, diuretics, or preparatory dehydration prior to iohexol injection administration. 5.5 Cardiovascular Adverse Reactions Life-threatening or fatal cardiovascular reactions including hypotension, shock, cardiac arrest have occurred with the parenteral administration of iohexol injection. Most deaths occur during injection or five to ten minutes later, with cardiovascular disease as the main aggravating factor. Cardiac decompensation, serious arrhythmias and myocardial ischemia or infarction can occur during coronary arteriography and ventriculography. Based on clinical literature, reported deaths from the administration of iodinated contrast agents range from 6.6 per million (0.00066%) to 1 in 10,000 (0.01%). Use the lowest necessary dose of iohexol in patients with congestive heart failure and always have emergency resuscitation equipment and trained personnel available. Monitor all patients for severe cardiovascular reactions. 5.6 Thromboembolic Events Serious, rarely fatal, thromboembolic events causing myocardial infarction and stroke can occur during angiocardiography procedures with iodinated contrast agents including iohexol. During these procedures, increased thrombosis and activation of the complement system occurs. Risk factors for thromboembolic events include: length of procedure, catheter and syringe material, underlying disease state and concomitant medications. To minimize thromboembolic events, use meticulous angiographic techniques and minimize the length of the procedure. Avoid blood remaining in contact with syringes containing iohexol, which increases the risk of clotting. Avoid angiocardiography in patients with homocystinuria because of the risk of inducing thrombosis and embolism. 5.7 Extravasation and Injection Site Reactions Extravasation of iohexol during intravenous or intra-arterial injection may cause tissue necrosis and/or compartment syndrome, particularly in patients with severe arterial or venous disease. Ensure intravenous or intra-arterial placement of catheters prior to injection. Monitor patients for extravasation and advise patients to seek medical care for progression of symptoms. 5.8 Thyroid Storm in Patients with Hyperthyroidism Thyroid storm has occurred after the intravenous or intra-arterial use of iodinated contrast agents in patients with hyperthyroidism, or with an autonomously functioning thyroid nodule. Evaluate the risk in such patients before use of iohexol. 5.9 Thyroid Dysfunction in Pediatric Patients 0 to 3 Years of Age Thyroid dysfunction characterized by hypothyroidism or transient thyroid suppression has been reported after both single exposure and multiple exposures to iodinated contrast media (ICM) in pediatric patients 0 to 3 years of age.
Side effects
The following clinically significant adverse reactions are described elsewhere in the labeling: Risks Associated with Intrathecal Administration of Iohexol Injection 140 mg Iodine/mL and 350 mg Iodine/mL [see Warnings and Precautions (5.1) ] Risks Associated with Parenteral Administration of Iohexol Oral Solution [see Warnings and Precautions (5.2) ] Hypersensitivity Reactions [see Warnings and Precautions (5.3) ] Acute Kidney Injury [see Warnings and Precautions (5.4) ] Cardiovascular Adverse Reactions [see Warnings and Precautions (5.5) ] Thromboembolic Events [see Warnings and Precautions (5.6) ] Thyroid Dysfunction in Pediatric Patients 0 to 3 Years of Age [see Warnings and Precautions (5.9) ] Severe Cutaneous Adverse Reactions [see Warnings and Precautions (5.12) ] Most common adverse reactions (incidence ≥ 1%) in adult patients Intrathecal: Headaches, pain including backache, neckache, stiffness and neuralgia, nausea, vomiting, dizziness. Intra-arterial or intravenous: Pain, vision abnormalities (including blurred vision and photomas), headache, taste perversion, arrhythmias including premature ventricular contractions (PVCs) and premature atrial contractions (PACs), angina/chest pain, nausea. Oral: Diarrhea, nausea, vomiting, abdominal pain, flatulence, headache. Body Cavity: Pain, swelling, heat sensation. ( 6.1 ) To report SUSPECTED ADVERSE REACTIONS, contact Amneal Pharmaceuticals LLC at 1-877-835-5472 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch. 6.1 Clinical Trials Experience Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice. Intrathecal Administration Adults Adverse reactions (≥ 1%) in 1,531 adult patients following intrathecal administration of iohexol injection in clinical trials are presented in Table 16. Table 16: Adverse Reactions (≥ 1%) in Adult Patients Following Intrathecal Administration of Iohexol Injection in Clinical Trials System Organ Class Adverse Reaction Incidence N = 1,531 Nervous system disorders Headaches 18% Musculoskeletal and connective tissue disorders Pain including backache, neckache, stiffness, neuralgia 8% Gastrointestinal disorders Nausea 6% Vomiting 3% Nervous System disorders Dizziness 2% Other adverse reactions (< 1%) were: Ear and labyrinth disorders : tinnitus, vertigo Eye disorders : photophobia General disorders and administration site conditions : sensation of heat Metabolism and nutrition disorders : loss of appetite Musculoskeletal and connective tissue disorders : feeling of heaviness Nervous system disorders : drowsiness, hypertonia, neuralgia, neurological changes, paresthesia, syncope Renal and urinary disorders : difficulty in micturition Skin and subcutaneous tissue disorders : sweating Vascular disorders : hypertension, hypotension Pediatric Patients The adverse reactions reported in pediatric patients following intrathecal administration of iohexol injection were generally similar to those reported in adults. A total of 152 pediatric patients were administered iohexol injection 180 mg iodine/mL intrathecally by lumbar puncture for pediatric myelography in clinical trials. Adverse reactions (≥ 1%) are presented in Table 17. Table 17: Adverse Reactions (≥ 1%) in Pediatric Patients Following Intrathecal Administration of Iohexol Injection 180 mg iodine/mL by Lumbar Puncture for Myelography in Clinical Trials System Organ Class Adverse Reaction Incidence N = 152 Nervous system disorders Headache 9% Gastrointestinal disorders Vomiting 6% Musculoskeletal and connective tissue disorders Backache 1.3% Other adverse reactions (< 1%) were: Gastrointestinal disorders: stomachache General disorders and administration site conditions: fever Nervous system disorders : neurological changes Psychiatric disorders : visual hallucination Skin and subcutaneous tissue disorders : hives Intra-arterial or Intravenous Administration Adults Adverse reactions (≥ 1%) in 1,485 adult patients following intra-arterial or intravenous administration of iohexol injection in clinical trials are presented in Table 18. Table 18: Adverse Reactions (≥ 1%) in Adult Patients Following Intra-arterial or Intravenous Administration of Iohexol Injection in Clinical Trials System Organ Class Adverse Reaction Incidence (N = 1,485) Cardiac disorders Arrhythmias including PVCs and PACs 2% Nervous system disorders Pain 3% Vision abnormalities including blurred vision and photomas 2% Taste perversion 1% Gastrointestinal disorders Nausea 2% Other adverse reactions (< 1%) were: Cardiac disorders: hypotension, cardiac failure, asystole, bradycardia, tachycardia, vasovagal reaction Respiratory, thoracic and mediastinal disorders: dyspnea, rhinitis, coughing, laryngitis Gastrointestinal disorders : vomiting, diarrhea, dyspepsia, cramp, dry mouth General disorders and administration site conditions: fever, shivering Nervous system disorders: cerebral infarction, convulsion, hemiparesis, motor and speech dysfunction, nystagmus, paresthesia, somnolence, transient ischemic attack, vertigo including dizziness and lightheadedness Musculoskeletal and connective tissue disorders: still neck Skin and subcutaneous tissue disorders : urticaria, abscess, pruritus, purpura Psychiatric disorders : anxiety, syncope Pediatric Patients Adverse reactions reported in pediatric patients following intra-arterial or intravenous administration of iohexol injection were generally similar in quality and frequency to those reported in adults. A total of 391 pediatric patients in clinical trials were administered iohexol injection 240 mg iodine/mL, 300 mg iodine/mL, or 350 mg iodine/mL by intra-arterial or intravenous injection for pediatric cardiac ventriculography, excretory urography and CT head imaging. Adverse reactions (≥ 1%) were vomiting (2%) and nausea (1%).
Drug interactions
7.1 Drug-Drug Interactions Metformin In patients with renal impairment, metformin can cause lactic acidosis. Iodinated contrast agents appear to increase the risk of metformin-induced lactic acidosis, possibly as a result of worsening renal function. Stop metformin at the time of, or prior to, iohexol injection administration in patients with an eGFR between 30 and 60 mL/min/1.73 m 2 ; in patients with a history of hepatic impairment, alcoholism or heart failure; or in patients who will be administered intra-arterial iodinated contrast. Re-evaluate eGFR 48 hours after the imaging procedure, and reinstitute metformin only after renal function is stable. Radioactive Iodine Iohexol may interfere with thyroid uptake of radioactive iodine (I-131 and I-123) and decrease therapeutic and diagnostic efficacy. Avoid thyroid therapy or testing for up to 6 weeks post iohexol injection. 7.2 Drug-Laboratory Test Interactions Protein-Bound Iodine Test Iodinated contrast agents, including iohexol, will temporarily increase protein-bound iodine in blood. Do not perform protein-bound iodine test for at least 16 days following administration of iohexol injection. However, thyroid function tests that do not depend on iodine estimation, e.g., T3 resin uptake or direct thyroxine assays, are not affected.
Use in specific populations
Lactation: A lactating woman may pump and discard breast milk for 10 hours after iohexol injection administration. ( 8.2 ) 8.1 Pregnancy Risk Summary Hysterosalpingography is contraindicated in pregnant women due to the potential risk to the fetus from an intrauterine procedure [see Contraindications (4) ]. There are no data with iohexol use in pregnant women to inform any drug-associated risks. Iohexol crosses the placenta and reaches fetal tissues in small amounts (see Data) . In animal reproduction studies, no developmental toxicity occurred with intravenous iohexol administration to rats and rabbits at doses up to 0.4 (rat) and 0.5 (rabbit) times the maximum recommended human intravenous dose (see Data) . The estimated background risk of major birth defects and miscarriage for the indicated population is unknown. All pregnancies have a background risk of birth defect, loss or other adverse outcomes. In the U.S. general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies is 2% to 4% and 15% to 20%, respectively. Data Human Data Literature reports show that intravenously administered iohexol crosses the placenta and is visualized in the digestive tract of exposed infants after birth. Animal Data Iohexol was neither embryotoxic nor teratogenic in either rats or rabbits at the following dose levels tested: 1 g iodine/kg, 2 g iodine/kg, 4 g iodine/kg in rats, administered intravenously to 3 groups of 25 dams once daily during days 6 through 15 of pregnancy; 0.3 g iodine/kg, 1 g iodine/kg, 2.5 g iodine/kg in rabbits, administered intravenously to 3 groups of 18 rabbits dosed once a day during days 6 through 18 of pregnancy. 8.2 Lactation Risk Summary Published literature reports that breast feeding after intravenous iohexol administration to the mother would result in the infant receiving an oral dose of approximately 0.7% of the maternal intravenous dose; however, lactation studies have not been conducted with oral, intrathecal, or intracavity administration of iohexol. There is no information on the effects of the drug on the breastfed infant or on milk production. Iodinated contrast agents are excreted unchanged in human milk in very low amounts with poor absorption from the gastrointestinal tract of a breastfed infant. Exposure to iohexol to a breastfed infant can be minimized by temporary discontinuation of breastfeeding (see Clinical Considerations). The developmental and health benefits of breastfeeding should be considered along with the mother’s clinical need for iohexol and any potential adverse effects on the breastfed infant from iohexol or from the underlying maternal condition. Clinical Considerations Interruption of breastfeeding after exposure to iodinated contrast agents is not necessary because the potential exposure of the breastfed infant to iodine is small. However, a lactating woman may consider interrupting breastfeeding and pumping and discarding breast milk for 10 hours (approximately 5 elimination half-lives) after iohexol injection administration to minimize drug exposure to a breastfed infant. 8.4 Pediatric Use Intrathecal Use The safety and effectiveness of iohexol have been established in pediatric patients aged 2 weeks and older for myelography and CT myelography (lumbar, thoracic, cervical, total columnar) and for CT cisternography. Use of iohexol is supported by controlled clinical studies in adults for myelography, in addition to clinical studies in pediatric patients undergoing myelography. The safety and effectiveness of iohexol have not been established for intrathecal use in pediatric patients less than 2 weeks of age. The safety and effectiveness of iohexol for CT cerebral ventriculography have not been established in pediatric patients. Intra-arterial or Intravenous Use Cardiac Ventriculography, Aortography and Pulmonary Angiography The safety and effectiveness of iohexol have been established in pediatric patients from birth to 17 years of age for cardiac ventriculography, aortography and pulmonary angiography. Use of iohexol is supported by controlled clinical studies in adults for cardiac ventriculography and aortography, in addition to controlled clinical studies in pediatric patients undergoing cardiac ventriculography, including aortography. Excretory Urography The safety and effectiveness of iohexol have been established in pediatric patients from birth to 17 years of age for excretory urography. Use of iohexol is supported by controlled clinical studies in adults for urography, in addition to controlled clinical studies in pediatric patients undergoing urography and clinical safety data in pediatric patients down to birth. CT of the Head and Body The safety and effectiveness of iohexol have been established in pediatric patients from birth to 17 years of age for CT imaging of the head and body. Use of iohexol is supported by controlled clinical studies in adults for head and body CT, in addition to clinical studies in pediatric patients undergoing head CT and in 69 pediatric patients undergoing CT of the abdomen after oral administration of diluted iohexol plus intravenous administration of iohexol injection. Selective Coronary Arteriography, Cerebral and Peripheral Arteriography, Intra-arterial Digital Subtraction Angiography, Peripheral Venography and Intravenous Digital Subtraction Angiography The safety and effectiveness of iohexol have not been established in pediatric patients for selective coronary arteriography, cerebral or peripheral arteriography, intra-arterial digital subtraction angiography, peripheral venography and intravenous digital subtraction angiography. Oral or Rectal Use Examination of the GI Tract The safety and effectiveness of iohexol have been established in pediatric patients, from birth to 17 years of age for examination of the GI tract.
Pregnancy
8.1 Pregnancy Risk Summary Hysterosalpingography is contraindicated in pregnant women due to the potential risk to the fetus from an intrauterine procedure [see Contraindications (4) ]. There are no data with iohexol use in pregnant women to inform any drug-associated risks. Iohexol crosses the placenta and reaches fetal tissues in small amounts (see Data) . In animal reproduction studies, no developmental toxicity occurred with intravenous iohexol administration to rats and rabbits at doses up to 0.4 (rat) and 0.5 (rabbit) times the maximum recommended human intravenous dose (see Data) . The estimated background risk of major birth defects and miscarriage for the indicated population is unknown. All pregnancies have a background risk of birth defect, loss or other adverse outcomes. In the U.S. general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies is 2% to 4% and 15% to 20%, respectively. Data Human Data Literature reports show that intravenously administered iohexol crosses the placenta and is visualized in the digestive tract of exposed infants after birth. Animal Data Iohexol was neither embryotoxic nor teratogenic in either rats or rabbits at the following dose levels tested: 1 g iodine/kg, 2 g iodine/kg, 4 g iodine/kg in rats, administered intravenously to 3 groups of 25 dams once daily during days 6 through 15 of pregnancy; 0.3 g iodine/kg, 1 g iodine/kg, 2.5 g iodine/kg in rabbits, administered intravenously to 3 groups of 18 rabbits dosed once a day during days 6 through 18 of pregnancy.
Pediatric use
8.4 Pediatric Use Intrathecal Use The safety and effectiveness of iohexol have been established in pediatric patients aged 2 weeks and older for myelography and CT myelography (lumbar, thoracic, cervical, total columnar) and for CT cisternography. Use of iohexol is supported by controlled clinical studies in adults for myelography, in addition to clinical studies in pediatric patients undergoing myelography. The safety and effectiveness of iohexol have not been established for intrathecal use in pediatric patients less than 2 weeks of age. The safety and effectiveness of iohexol for CT cerebral ventriculography have not been established in pediatric patients. Intra-arterial or Intravenous Use Cardiac Ventriculography, Aortography and Pulmonary Angiography The safety and effectiveness of iohexol have been established in pediatric patients from birth to 17 years of age for cardiac ventriculography, aortography and pulmonary angiography. Use of iohexol is supported by controlled clinical studies in adults for cardiac ventriculography and aortography, in addition to controlled clinical studies in pediatric patients undergoing cardiac ventriculography, including aortography. Excretory Urography The safety and effectiveness of iohexol have been established in pediatric patients from birth to 17 years of age for excretory urography. Use of iohexol is supported by controlled clinical studies in adults for urography, in addition to controlled clinical studies in pediatric patients undergoing urography and clinical safety data in pediatric patients down to birth. CT of the Head and Body The safety and effectiveness of iohexol have been established in pediatric patients from birth to 17 years of age for CT imaging of the head and body. Use of iohexol is supported by controlled clinical studies in adults for head and body CT, in addition to clinical studies in pediatric patients undergoing head CT and in 69 pediatric patients undergoing CT of the abdomen after oral administration of diluted iohexol plus intravenous administration of iohexol injection. Selective Coronary Arteriography, Cerebral and Peripheral Arteriography, Intra-arterial Digital Subtraction Angiography, Peripheral Venography and Intravenous Digital Subtraction Angiography The safety and effectiveness of iohexol have not been established in pediatric patients for selective coronary arteriography, cerebral or peripheral arteriography, intra-arterial digital subtraction angiography, peripheral venography and intravenous digital subtraction angiography. Oral or Rectal Use Examination of the GI Tract The safety and effectiveness of iohexol have been established in pediatric patients, from birth to 17 years of age for examination of the GI tract. Use of iohexol is supported by controlled studies in adults for examination of the GI tract, in addition to clinical studies in pediatric patients undergoing examination of the GI tract. CT of the Abdomen and Pelvis in Conjunction with Intravenous Use The safety and effectiveness of iohexol for CT of the abdomen and pelvis have been established in pediatric patients from birth to 17 years of age. Use is supported by clinical trials in adults, in addition to clinical studies in 69 pediatric patients undergoing CT of the abdomen. Intraarticular Use The safety and effectiveness of iohexol have not been established in pediatric patients for arthrography. Body Cavity Use Voiding Cystourethrography Iohexol is indicated for use in pediatric patients from birth to 17 years of age for voiding cystourethrography (VCU). Use for voiding cystourethrography is supported by clinical studies in 51 pediatric patients undergoing VCU. ERCP, Herniography, and Hysterosalpingography The safety and effectiveness of iohexol have not been established in pediatric patients for ERCP, herniography, or hysterosalpingography. In general, the frequency of adverse reactions in pediatric patients was similar to that seen in adults [ s ee Adverse Reactions (6.1) ] . Pediatric patients at higher risk of experiencing adverse events during contrast-medium administration may include those having asthma, a sensitivity to medication and/or allergens, congestive heart failure, a serum creatinine greater than 1.5 mg/dL or those less than 12 months of age. Thyroid function tests indicative of thyroid dysfunction, characterized by hypothyroidism or transient thyroid suppression have been reported following iodinated contrast media administration in pediatric patients, including term and preterm neonates. Some patients were treated for hypothyroidism. After exposure to iodinated contrast media, individualize thyroid function monitoring in pediatric patients 0 to 3 years of age based on underlying risk factors, especially in term and preterm neonates [see Warnings and Precautions (5.9) and Adverse Reactions (6.2) ] .
Geriatric use
8.5 Geriatric Use In clinical studies of iohexol for CT of the head and body, 52 (17%) of patients were 70 and over. No overall differences in safety were observed between these patients and younger patients. Other reported clinical experience has not identified differences in safety and effectiveness between the elderly and younger patients. Iohexol is substantially excreted by the kidney, and the risk of adverse reactions to iohexol may be greater in patients with impaired renal function. Because elderly patients are more likely to have decreased renal function, care should be taken in dose selection and it may be useful to monitor renal function.
Overdosage
The adverse effects of overdosage in intra-arterial or intravenous administration are life-threatening and affect mainly the pulmonary and cardiovascular systems. The symptoms include: cyanosis, bradycardia, acidosis, pulmonary hemorrhage, convulsions, coma and cardiac arrest. Treatment of an overdosage is directed toward the support of all vital functions and prompt institution of symptomatic therapy. Iohexol can be dialyzed.
Description
Iohexol, USP is a nonionic radiographic contrast agent available as: Iohexol injection for intrathecal, intra-arterial, intravenous, oral, rectal, intraarticular and body cavity use. The chemical name of iohexol, USP is N,N’ -Bis(2,3-dihydroxypropyl)-5-[ N -(2,3-dihydroxypropyl) acetamido]-2,4,6-triiodoisophthalamide with a molecular weight of 821.14 (iodine content 46.36%). Iohexol has the following structural formula: Iohexol Injection, USP is a sterile, pyrogen-free, clear, colorless to pale yellow solution available in following concentrations of iodine: Iohexol Injection USP, 300 mg iodine/mL: Each mL contains 647 mg iohexol, USP (providing 300 mg organically bound iodine) and the following inactive ingredients: 0.1 mg edetate calcium disodium, USP; 1.21 mg tromethamine, USP and water for injection. Iohexol Injection USP, 350 mg iodine/mL: Each mL contains 755 mg iohexol, USP (providing 350 mg organically bound iodine) and the following inactive ingredients: 0.1 mg edetate calcium disodium, USP; 1.21 mg tromethamine, USP and water for injection. The pH is adjusted between 6.8 and 7.7 with hydrochloric acid or sodium hydroxide. Iohexol injection contain no preservatives and no ingredient made from a gluten-containing grain (wheat, barley, or rye). Iohexol injection have the following physical properties: Table 21: Physicochemical Properties of Iohexol Injection Dosage Form Concentration (mg iodine/mL) Osmolality * (mOsmol/kg water) Absolute Viscosity (cP) Specific Gravity 20°C 37°C 37°C Injection 300 659 11.48 6.05 1.344 350 774 21.48 12.16 1.4054 * By Freezing Point Depression Osmometer. Iohexol injection has osmolalities from approximately 2.4 times that of plasma (285 mOsmol/kg water) or cerebrospinal fluid (301 mOsmol/kg water) as shown in the above table and are hypertonic. 1
Mechanism of action
12.1 Mechanism of Action The iodine atoms in iohexol provide attenuation of X-rays in direct proportion to the concentration of iohexol. Since concentration changes over time, iohexol provides time-dependent image contrast which may assist in visualizing body structures.
How supplied
How Supplied Iohexol Injection, USP is clear, colorless to pale yellow solution available in the following presentations: Dosage Form Concentration (mg iodine/mL) Package Size Package Type & Material Sale Unit NDC Injection 300 50 mL Single-Dose Polymer Bottles Carton of 10 80830-2466-2 75 mL Single-Dose Polymer Bottles Carton of 10 80830-2467-2 100 mL Single-Dose Polymer Bottles Carton of 10 80830-2468-2 350 50 mL Single-Dose Polymer Bottles Carton of 10 80830-2471-2 75 mL Single-Dose Polymer Bottles Carton of 10 80830-2472-2 100 mL Single-Dose Polymer Bottles Carton of 10 80830-2473-2 The container closure system components (bottle, stopper and cap) of iohexol injection are not made with natural rubber latex. Storage and Handling Iohexol Injection: Store at 20° to 25°C (68° to 77°F); excursions permitted between 15° to 30°C (59° to 86°F) [see USP Controlled Room Temperature]. May be stored in a contrast media warmer for up to one month, not to exceed 37°C (98.6°F). Protect from light. Do not freeze. Discard any product that is inadvertently frozen, as freezing may compromise the closure integrity of the immediate container.
Patient information
Hypersensitivity Reactions Advise the patient concerning the risk of hypersensitivity reactions that can occur both during and after iohexol injection administration. Advise the patient to report any signs or symptoms of hypersensitivity reactions during the procedure and to seek immediate medical attention for any signs or symptoms experienced after discharge [see Warnings and Precautions (5.3) ]. Advise patients to inform their physician if they develop a rash after receiving iohexol injection [see Warnings and Precautions (5.12) ]. Acute Kidney Injury Advise the patient concerning appropriate hydration to decrease the risk of contrast-induced acute kidney injury [see Warnings and Precautions (5.4) ] . Extravasation If extravasation occurs during injection, advise patients to seek medical care for progression of symptoms [see Warnings and Precautions (5.7) ]. Lactation Advise a lactating woman that interruption of breastfeeding is not necessary. However, to avoid any exposure, a lactating woman may consider pumping and discarding breast milk for 10 hours after iohexol injection administration [see Use in Specific Populations (8.2) ]. Thyroid Dysfunction Advise parents/caregivers about the risk of developing thyroid dysfunction after iohexol injection administration. Advise parents/caregivers about when to seek medical care for their child to monitor for thyroid function [see Warnings and Precautions (5.9) ]. Manufactured by: Amneal Pharmaceuticals Pvt. Ltd. Ahmedabad 382110, INDIA Distributed by: Amneal Pharmaceuticals LLC Bridgewater, NJ 08807 Rev. 06-2026-01
Label text from the FDA structured product label by Amneal Pharmaceuticals Private Limited (revised Jun 30, 2026). Long sections are shortened; the complete label is on DailyMed.
Active ingredients
- Iohexol in 6 products
Iohexol NDC products (6)
| NDC | Strength & form | Labeler | Type |
|---|---|---|---|
| 80830-2466 | Iohexol 300 mg/mL Injection, Solution | Amneal Pharmaceuticals Private Limited | ANDA |
| 80830-2467 | Iohexol 300 mg/mL Injection, Solution | Amneal Pharmaceuticals Private Limited | ANDA |
| 80830-2468 | Iohexol 300 mg/mL Injection, Solution | Amneal Pharmaceuticals Private Limited | ANDA |
| 80830-2471 | Iohexol 350 mg/mL Injection, Solution | Amneal Pharmaceuticals Private Limited | ANDA |
| 80830-2472 | Iohexol 350 mg/mL Injection, Solution | Amneal Pharmaceuticals Private Limited | ANDA |
| 80830-2473 | Iohexol 350 mg/mL Injection, Solution | Amneal Pharmaceuticals Private Limited | ANDA |
Frequently asked questions
What is Iohexol used for?
Iohexol is a radiographic contrast agent indicated for intrathecal, intra-arterial, intravenous, oral, rectal, intraarticular and body cavity imaging procedures in adults and pediatric patients. ( 1 ) 1.1 Intrathecal Procedures ‡ Iohexol injection is indicated for: Myelography and computerized tomography (CT) myelography (lumbar, thoracic, cervical, total columnar) in adults and pediatric…
What are the side effects of Iohexol?
The following clinically significant adverse reactions are described elsewhere in the labeling: Risks Associated with Intrathecal Administration of Iohexol Injection 140 mg Iodine/mL and 350 mg Iodine/mL [see Warnings and Precautions (5.1) ] Risks Associated with Parenteral Administration of Iohexol Oral Solution [see Warnings and Precautions (5.2) ] Hypersensitivity Reactions [see Warnings and… See the full label for the complete list.
Who makes Iohexol?
Iohexol is listed by 1 labeler in the FDA NDC directory, including Amneal Pharmaceuticals Private Limited.