Gadopentetate Dimeglumine

What it is and how it works

Gadopentetate is a paramagnetic gadolinium(III) chelate with DTPA that shortens the T1 relaxation time of nearby water protons, increasing signal intensity on T1-weighted MRI. After intravenous injection it distributes in the extracellular fluid, does not cross an intact blood–brain barrier and is excreted unchanged by the kidneys.

Indications

Contrast enhancement in MRI of the central nervous system and body; following EMA review in 2017, intravenous use of linear agents such as gadopentetate was suspended in the EU, and the low-concentration formulation remains authorised there only for intra-articular MR arthrography.

Dosage and administration (summary)

Intravenous MRI: usually 0.1 mmol/kg (0.2 mL/kg of the 0.5 mmol/mL solution) as a single injection, using the lowest dose providing adequate enhancement; intra-articular formulations are dosed according to the joint and protocol.

Contraindications

Hypersensitivity to gadolinium-based agents; intravenous use is contraindicated in patients with severe renal impairment (GFR below 30 mL/min/1.73 m²), in the perioperative liver transplant period and in neonates up to 4 weeks.

Warnings and precautions

Linear gadolinium agents carry a higher risk of nephrogenic systemic fibrosis in renal impairment and of gadolinium retention in the brain and other tissues than macrocyclic agents; renal function should be assessed before use and repeat doses avoided. Hypersensitivity reactions, including anaphylaxis, may occur, so resuscitation facilities must be available; extravasation can cause tissue reactions.

Pregnancy

Avoid in pregnancy unless the clinical condition requires gadolinium-enhanced imaging.

Storage and supply

Store below 30 °C, protected from light; do not freeze.

Source: reference summary prepared from the EU SmPC/EPAR, BNF and WHO Model Formulary. The approved product information in Iran governs.