Gadodiamide

Gadodiamide, sold under the brand name Omniscan, is a gadolinium-based MRI contrast agent (GBCA), used in magnetic resonance imaging (MRI) procedures to assist in the visualization of blood vessels.

Gadodiamide

Clinical data
Trade names	Omniscan
Other names	2-[bis[2-(carboxylatomethyl-(methylcarbamoylmethyl)amino)ethyl]amino]acetate; gadolinium(+3) cation
AHFS/Drugs.com	Micromedex Detailed Consumer Information
License data	US DailyMed: Gadodiamide
Routes of administration	Intravenous
ATC code	V08CA03 (WHO)
Legal status
Legal status	CA: ℞-only[1] US: ℞-only[2] EU: Rx-only[3]
Pharmacokinetic data
Protein binding	negligible
Metabolism	not metabolized
Elimination half-life	77.8 minutes
Excretion	Kidney
Identifiers
IUPAC name gadolinium(III) 5,8-bis(carboxylatomethyl)-2-[2-(methylamino)-2-oxoethyl]-10-oxo-2,5,8,11-tetraazadodecane-1-carboxylate hydrate
CAS Number	131410-48-5 N 122795-43-1 (hydrate)
PubChem CID	153921
DrugBank	DB00225 Y
ChemSpider	135661 Y
UNII	84F6U3J2R6
KEGG	D01645 Y
ChEBI	CHEBI:37333 Y
ChEMBL	ChEMBL1200346 N
CompTox Dashboard (EPA)	DTXSID9048647
Chemical and physical data
Formula	C16H28GdN5O9
Molar mass	591.68 g·mol−1
3D model (JSmol)	Interactive image
SMILES [Gd+3].[O-]C(=O)CN(CC(=O)NC)CCN(CCN(CC([O-])=O)CC(=O)NC)CC([O-])=O
InChI InChI=1S/C16H29N5O8.Gd/c1-17-12(22)7-20(10-15(26)27)5-3-19(9-14(24)25)4-6-21(11-16(28)29)8-13(23)18-2;/h3-11H2,1-2H3,(H,17,22)(H,18,23)(H,24,25)(H,26,27)(H,28,29);/q;+3/p-3 Y Key:HZHFFEYYPYZMNU-UHFFFAOYSA-K Y
NY (what is this?)  (verify)

Medical uses

Further information: MRI contrast agent

A bottle of Omniscan contrast agent.

Gadodiamide is a contrast medium used for cranial and spinal magnetic resonance imaging (MRI) and for general MRI of the body after intravenous administration. It provides contrast enhancement and facilitates visualisation of abnormal structures or lesions in various parts of the body including the central nervous system (CNS). It crosses intact the blood brain barrier.^[4]

Adverse effects

Gadodiamide is one of the main GBCA associated with nephrogenic systemic fibrosis (NSF), a toxic reaction occurring in some people with kidney problems.^[5] No cases have been seen in people with normal kidney function.^[6]

A 2015 study found gadolinium deposited in the brain tissue of people who had received gadodiamide.^[7] Other studies using post-mortem mass spectrometry found most of the deposit remained at least 2 years after an injection and deposit also in individuals with no kidney issues.

In vitro studies found it to be neurotoxic.^[8]

An Italian task force recommended that breastfeeding mothers precautionally avoid any contrast agent, such as gadodiamide, that has been associated with nephrogenic systemic fibrosis.^[9]

Like other gadolinium-based contrast agents (GBCAs), gadodiamide may cause a range of adverse reactions. The most common include mild symptoms such as nausea, headache, or injection site discomfort. However, rare but serious reactions have been reported.

Hypersensitivity and anaphylaxis

Gadodiamide can cause severe allergic or hypersensitivity reactions, including anaphylaxis—a potentially life-threatening condition requiring immediate medical attention and treatment with epinephrine (adrenaline). Post-marketing surveillance and case studies have documented such events in patients who received gadodiamide.^[10]

Data from the U.S. FDA Adverse Event Reporting System (FAERS) also list anaphylaxis and other hypersensitivity reactions among the reported adverse effects associated with gadodiamide.^[11]

Patients with a known history of allergic reactions to contrast media or other drugs should inform their healthcare provider before undergoing imaging studies with gadodiamide. In high-risk individuals, premedication and pre-screening protocols may be considered to mitigate the risk of severe reactions.

Society and culture

Gadodiamide was suspended along with gadopentetic acid (Magnevist) by the European Medicines Agency in 2017.^[12]