Medicinehospital

Iohexol

An iodine-based contrast agent used for X-ray and CT imaging procedures.

Clinical information

Common uses

imaging of blood vessels, spine, joints and body cavities
oral or rectal imaging of the digestive tract

Common side effects

headache
pain, including back pain
feeling or being sick
dizziness
blurred vision or taste changes

Cautions

wrong-strength spinal injection can be fatal
severe allergic reactions can occur
can cause acute kidney injury — keep well hydrated
heart complications can occur during or after injection

Interactions

metformin (stop around the scan — lactic acidosis risk)
radioactive iodine tests or treatment (avoid for 6 weeks)

Pregnancy: not for womb (hysterosalpingography) imaging in pregnancy; otherwise limited data

Reference information, not medical advice — always follow your doctor or pharmacist. Source: DailyMed, dailymed.nlm.nih.gov, iohexol injection label, setid ff9456ef-c45a-450d-9004-a684af2bcc59 (accessed 2026-08-16)

Approved brands & formulations2

Brand name	Dosage form	Strength	Importer	Category
Omnipaque	Parenteral ( Injection )	350 mgI/ml(100ml)	—	hospital
Optiscan 350	Parenteral ( Injection- Intravenous )	755.0mg/ml(100ml) USP	—	hospital