As many individuals plan their health checkups for the second half of the year, health authorities emphasize that obtaining accurate diagnostic results requires strict adherence to preparation guidelines. Alongside standard protocols such as maintaining an 8-hour fast and avoiding alcohol or high-fat meals, patients must carefully review their current medication regimens with their physicians.

According to the Ministry of Food and Drug Safety (MFDS) YouTube channel on the 2nd, medications that regulate blood sugar or prevent blood clotting require special caution, as continuing them during a fast or specialized procedure can introduce significant health risks.

1. Diabetes Medications and the Risk of Hypoglycemia

Diabetes medications are designed to lower elevated blood glucose levels. However, standard health checkups require fasting for a prolonged period. If insulin or oral hypoglycemic agents are taken as usual during a fast, the patient faces a severe risk of hypoglycemia (low blood sugar).

Severe hypoglycemia can lead to loss of consciousness or secondary accidents such as falls. Therefore, fasting must be accompanied by the suspension of diabetes medications as advised by a doctor.

Special Precaution: Contrast Media and Metformin
Patients scheduled for procedures utilizing contrast agents—such as CT scans or angiography—must verify whether they are taking metformin-containing diabetes medications.

Iodinated contrast agents used in CT scans can temporarily impair renal (kidney) function. Because approximately 90% of metformin is excreted through the kidneys, concurrent administration of contrast media and metformin can dramatically increase the risk of metformin-induced renal complications. Consequently, metformin must be discontinued starting on the day of the procedure and withheld for up to 48 hours post-procedure.

2. Anticoagulants and Antiplatelet Agents (Blood Thinners)

Blood thinners such as aspirin, warfarin, clopidogrel (Plavix), cilostazol (Pletal), and Non-Vitamin K oral anticoagulants (NOACs)—including Xarelto, Lixiana, Eliquis, and Pradaxa—may need to be suspended before invasive procedures like endoscopies.

These medications are prescribed to patients with histories of myocardial infarction (heart attack), stroke, or venous thrombosis to prevent abnormal blood clotting by thinning the blood.

During an endoscopy, physicians frequently perform tissue biopsies or remove polyps. If a patient is taking anticoagulants, bleeding at the site may not stop promptly, creating dangerous complications. Because these drugs have long-lasting systemic effects, unlike short-acting diabetes medications, they typically require discontinuation 3 to 7 days in advance rather than just one day prior.

Critical Medical Advice: Discontinuing blood thinners carries the risk of thromboembolic events (such as myocardial infarction) if underlying conditions worsen. Patients must never stop these medications independently; always consult a specialist or primary physician to weigh the bleeding risk against the risk of underlying disease exacerbation.