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Omnipaque 210 Side Effects

Generic name: iohexol

Medically reviewed by Last updated on Apr 4, 2024.

Note: This document contains side effect information about iohexol. Some dosage forms listed on this page may not apply to the brand name Omnipaque 210.

Applies to iohexol: oral solution. Other dosage forms:

Serious side effects of Omnipaque 210

Along with its needed effects, iohexol (the active ingredient contained in Omnipaque 210) may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor or nurse immediately if any of the following side effects occur while taking iohexol:

Less common

Incidence not known

Other side effects of Omnipaque 210

Some side effects of iohexol may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects.

Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

Less common


For Healthcare Professionals

Applies to iohexol: injectable solution, oral solution.


The most frequently reported adverse reactions are headache, mild to moderate pain including backache, neckache and stiffness, nausea, and vomiting. These reactions usually occur 1 to 10 hours after injection, and almost all occur within 24 hours. They are usually mild to moderate in degree, lasting for a few hours, and usually disappearing within 24 hours.[Ref]


Very common (10% or more): Diarrhea (oral/body cavity routes)

Common (1% to 10%): Nausea, vomiting, pancreatitis (endoscopic retrograde cholangiopancreatography), lower abdominal pain (hysterosalpingography)

Uncommon (0.1% to 1%): Abdominal pain, stomach ache

Rare (0.01% to 0.1%): Diarrhea

Very rare (less than 0.01%): Tenderness and/or enlargement of the salivary glands ("iodide mumps"), abdominal discomfort

Frequency not reported: Aggravation of pancreatitis, acute pancreatitis[Ref]

Nervous system

Very common (10% or more): Headache (may be severe and prolonged)

Common (1% to 10%): Dizziness (2%), neuralgia

Uncommon (0.1% to 1%): Aseptic meningitis syndrome (including chemical meningitis), visual hallucinations, somnolence, hemiparesis, transient ischemic attack, cerebral infarction, syncope

Rare (0.01% to 0.1%): Seizure, neurological changes, drowsiness, transitory peripheral neuropathies (sensory and/or motor or nerve root disturbances, myelitis, persistent leg muscle pain or weakness, 6th nerve palsy, or cauda equina syndrome)

Very rare (less than 0.01%): Dysgeusia (transient metallic taste), disturbance in consciousness, transient contrast-induced encephalopathy (including transient memory loss, coma, stupor, retrograde amnesia), sensory abnormalities (including hypoesthesia), paraesthesia, tremor

Frequency not reported: Syncope vasovagal, motor dysfunction (including speech disorder, aphasia, dysarthria), disorientation, abnormal electroencephalogram, meningism[Ref]

Rarely, headaches may be severe or persist for days. Headache is often accompanied by nausea and vomiting and tends to be more frequent and persistent in patients not optimally hydrated.

Aseptic meningitis syndrome was usually preceded by pronounced headaches, nausea and vomiting. Onset usually occurred about 12 to 18 hours postprocedure. Prominent features were meningismus, fever, sometimes with oculomotor signs and mental confusion. Lumbar puncture revealed a high white cell count, high protein content often with a low glucose level and with absence of organisms. The condition usually started to clear spontaneously about 10 hours after onset, with complete recovery over 2 to 3 days.[Ref]


Very common (10% or more): Pain

Common (1% to 10%): Feeling hot

Uncommon (0.1% to 1%): Discomfort, fever, hives

Rare (0.01% to 0.1%): Pyrexia, asthenic conditions (including malaise, fatigue), feeling of heaviness, tinnitus, vertigo

Very rare (less than 0.01%): Shivering (chills)

Frequency not reported: Transient hearing loss[Ref]


Common (1% to 10%): Blood amylase increased

Uncommon (0.1% to 1%): Hypoglycemia in pediatrics (0.3%)

Rare (less than 0.1%): Loss of appetite

Frequency not reported: Iodism[Ref]


Common (1% to 10%): Back pain

Rare (less than 0.1%): Neck pain, pain in extremity, hypertonia

Frequency not reported: Muscle spasm, arthralgia, arthritis, muscle cramps, fasciculation or myoclonia, spinal convulsion, spasticity, stiff neck[Ref]

Severe pain may often result from undue use of pressure or the injection of large volumes. Joint swelling after injection is less with iohexol than with high osmolar ionic contrast medium. These types of reactions are generally procedurally dependent and of greater frequency when double-contrast technique is employed.[Ref]


Common (1% to 10%): Vision abnormalities (including blurred vision and photomas) (2%)

Uncommon (0.1% to 1%): Nystagmus (less than 0.3%)

Rare (less than 0.1%): Photophobia, ocular muscles weakness

Frequency not reported: Transient cortical blindness[Ref]


Common (1% to 10%): Transient increase in serum creatinine (contrast induced nephropathy may occur)

Rare (less than 0.1%): Impairment of renal function including acute renal failure[Ref]


Uncommon (0.1% to 1%): Angina, chest pain, anemia in pediatrics(0.3%)

Rare (0.01% to 0.1%): Bradycardia, arrhythmia, hypotension, hypertension

Very rare (less than 0.01%): Myocardial infarction, flushing

Frequency not reported: Severe cardiac complications (including cardiac arrest, cardio-respiratory arrest), spasm of coronary arteries, chest pain, shock, arterial spasm, ischemia, thrombophlebitis, thrombosis[Ref]


Uncommon (0.1% to 1%): Urticaria, purpura, abscess, pruritus

Frequency not reported: Severe pustular or exfoliative or bullous dermatitis, Stevens-Johnson syndrome, erythema multiforme, toxic epidermal necrolysis, acute generalized exanthematous pustulosis, rash with eosinophilia and systemic symptoms, psoriasis flare-up[Ref]


Uncommon (0.1% to 1%): Dyspnea, rhinitis, coughing, laryngitis

Rare (0.01% to 0.1%): Cough

Very rare (less than 0.01%): Non-cardiogenic pulmonary edema

Frequency not reported: Severe respiratory symptoms and signs, bronchospasm, laryngospasm, asthma attack[Ref]


Rare (less than 0.1%): Difficulty in micturition[Ref]


The hypersensitivity reactions may appear either immediately after the injection or up to a few days later.

Hypersensitivity reactions may occur irrespectively of the dose and mode of administration, and mild symptoms may represent the first signs of a serious anaphylactoid reaction/shock.[Ref]

Rare (less than 0.1%): Hypersensitivity (including dyspnea, rash, erythema, urticaria, pruritus, skin reaction, vasculitis, angioneurotic edema, laryngeal edema, laryngospasm, bronchospasm or non-cardiogenic pulmonary edema)

Frequency not reported: Anaphylactic/anaphylactoid reaction, anaphylactic/anaphylactoid shock[Ref]


Very rare (less than 0.01%): Sweating

Frequency not reported: Thyrotoxicosis, transient hypothyroidism (premature infants, neonates premature breast fed infant, and in other children)[Ref]


Frequency not reported: Administration site reactions, including extravasation[Ref]


Frequency not reported: Confusion, anxiety[Ref]


1. Cerner Multum, Inc. "UK Summary of Product Characteristics."

2. (2007) "Product Information. Omnipaque 180 (iohexol)." Amersham Health

3. Cerner Multum, Inc. "Australian Product Information."

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Some side effects may not be reported. You may report them to the FDA.