Cyclolux (Gadoteric Acid)

Cyclolux is a gadolinium-based contrast agent used in magnetic resonance imaging (MRI) to enhance the visibility of various organs and tissues. It is particularly effective in improving the delineation of lesions and abnormalities during MRI scans.

• Central Nervous System (CNS) Imaging: Enhances the visualisation of brain, spinal cord, and adjacent tissue defects (lesions).
• Whole Body MRI: Improves the imaging of liver, kidneys, pancreas, pelvis, lungs, heart, breast, and musculoskeletal system.
• MR Angiography: Facilitates the imaging of arteries, except coronary arteries, to detect defects (lesions) and narrowing (stenosis).

• Gadoteric acid, the active ingredient in Cyclolux, works by shortening the T1 relaxation time of nearby water protons. This enhancement of signal intensity on T1-weighted MRI scans improves the contrast and clarity of the images, making it easier to identify and delineate abnormalities in various organs and tissues. The mechanism of action is based on the paramagnetic properties of gadolinium, which alters the magnetic environment of water molecules, thereby enhancing the MRI signal.

Cyclolux, like other gadolinium-based contrast agents, may cause side effects ranging from mild to severe. It is important to be aware of these potential effects before administration.

Common Side Effects

• Nausea: Mild to moderate nausea may occur after administration.
• Headache: Some patients may experience headaches following the injection.
• Dizziness: Lightheadedness or dizziness can be a common side effect.
• Injection Site Reactions: Redness, pain, or swelling at the injection site may occur.
• Vomiting: Some patients may experience vomiting after the injection.
• Diarrhoea: Mild gastrointestinal disturbances, including diarrhoea, can occur.

Serious or Rare Side Effects

• Nephrogenic Systemic Fibrosis (NSF): A rare but serious condition that can occur in patients with severe renal impairment.
• Allergic Reactions: Severe allergic reactions, including anaphylaxis, can occur but are rare.
• Nephrogenic Fibrosing Dermopathy: Similar to NSF, this condition affects the skin and connective tissues.
• Acute Kidney Injury: In rare cases, administration of gadoteric acid can lead to acute kidney injury.

Cyclolux should be used with caution in certain patient populations and under specific conditions to ensure safety and efficacy.

• Renal Impairment: Use with caution in patients with renal impairment, as the risk of nephrogenic systemic fibrosis (NSF) is increased. Dose adjustment may be necessary.
• Allergic Reactions: Patients with a history of allergic reactions to gadolinium-based contrast agents should be monitored closely.
• Pregnancy: The safety of Cyclolux in pregnant women has not been established. It should be used during pregnancy only if clearly needed.
• Breastfeeding: It is not known whether gadoteric acid is excreted in human milk. Caution should be exercised when administering to breastfeeding women.
• Children: Use in children should be carefully considered due to immature renal function, especially in neonates and infants.
• Store at room temperature: Keep this medicine out of the sight and reach of children. Do not use after the expiry date stated on the vial and carton.

Cyclolux may interact with other medications or substances, potentially altering its effectiveness or increasing the risk of side effects.

Major Interactions (Avoid)

• Other Gadolinium-Based Contrast Agents: Avoid concurrent use with other gadolinium-based contrast agents to prevent cumulative toxicity.
• Nephrotoxic Drugs: Avoid concomitant use with nephrotoxic drugs to reduce the risk of acute kidney injury.

Moderate Interactions (Monitor Closely)

• Diuretics: Monitor renal function closely when used concurrently with diuretics, as they may increase the risk of nephrotoxicity.
• Nonsteroidal Anti-Inflammatory Drugs (NSAIDs): Monitor for signs of renal impairment when used with NSAIDs, as they may exacerbate nephrotoxicity.
• Aminoglycosides: Monitor renal function when used with aminoglycosides, as they may increase the risk of nephrotoxicity.