Medications to Stop Before Your MRI with Contrast

If you are scheduled for an MRI with contrast, your doctor may ask you to adjust certain medications. Gadolinium-based contrast agents help radiologists see detailed images of your organs, blood vessels, and tissues — but some drugs can interact with the contrast or the MRI process itself.

What Is Gadolinium Contrast?

Gadolinium is a metallic element used in MRI contrast dyes. When injected into your bloodstream, it enhances the visibility of inflammation, tumors, and blood vessels. The FDA monitors gadolinium agents and considers them safe for most patients.

Medications That May Need to Be Stopped

Always follow your specific doctor instructions. These are general categories that may require adjustment:

Metformin (Glucophage) - Why: Although metformin is more commonly paused for CT contrast (iodine-based), some facilities also exercise caution with gadolinium in patients with reduced kidney function - Typical instruction: Stop 48 hours before the exam if your kidney function is borderline - Resume: After your doctor confirms your kidney labs are normal

Iron Supplements - Why: High-dose iron supplements can affect image quality in some abdominal MRI studies - Typical instruction: Stop 24 hours before the exam - Resume: Immediately after the scan

Certain Blood Pressure Medications - Why: Some ACE inhibitors and ARBs can affect kidney function tests that are checked before contrast administration - Typical instruction: Take as usual unless your doctor says otherwise - Note: Do not stop blood pressure medications without medical guidance

NSAIDs (Ibuprofen, Naproxen) - Why: Long-term NSAID use can reduce kidney function, which affects how your body processes gadolinium - Typical instruction: Your doctor may check kidney labs before clearing you for contrast

Medications You Should NOT Stop

Many patients worry about stopping all medications. In most cases, you should continue taking:

• Heart medications (beta-blockers, statins)
• Thyroid medications
• Anti-seizure medications
• Antidepressants and anxiety medications
• Birth control

Always take essential medications with a small sip of water, even if you are fasting for the exam.

Allergy Pre-Medication

If you have a known allergy to gadolinium contrast, your doctor will prescribe pre-medication — typically:

• Prednisone (a steroid) taken 13 hours, 7 hours, and 1 hour before the exam
• Diphenhydramine (Benadryl) taken 1 hour before

Do not skip the pre-medication doses. They significantly reduce the risk of an allergic reaction, according to the American College of Radiology.

The Kidney Connection

Your kidneys filter gadolinium out of your body within 24 hours. If your kidney function is reduced, the contrast stays in your system longer, which increases the risk of a rare condition called nephrogenic systemic fibrosis (NSF).

This is why your imaging center may require a blood test (creatinine/GFR) before your MRI with contrast. At AMI, we review your kidney function before administering any contrast agent.

Before Your Appointment

To prepare for your MRI with contrast:

1. Tell your doctor about all medications — including supplements and over-the-counter drugs
2. Mention any kidney problems — even mild ones
3. Report previous contrast reactions — from any type of imaging
4. Follow fasting instructions — Typically 4 hours of no solid food
5. Stay hydrated — Drink water before and after the scan

Schedule Your MRI

Have questions about your medications before an MRI with contrast? Call Advanced Medical Imaging at (727) 398-5999. Our team will review your medication list and provide clear instructions.

Sources: - FDA — Gadolinium Safety - ACR — Contrast Manual