In which situations should gilteritinib absolutely not be taken?

In which situations should gilteritinib absolutely not be taken?

You must not use gilteritinib if you are allergic to gilteritinib or any of its other ingredients. Allergic reactions may manifest as rash, hives, swelling of the face or throat, difficulty breathing, etc. In addition, caution is required if you are experiencing certain serious infections or organ dysfunction. Before starting treatment, be sure to provide your doctor with a complete medical history and allergy history. If you have had severe adverse reactions to similar drugs in the past, you should also inform your doctor. Do not share gilteritinib with others, even if they have the same symptoms, as individual differences may lead to serious harm.

Serious adverse reaction to watch for – Differentiation syndrome

During the first three months of gilteritinib treatment, especially as early as day 1 after starting the medication, a serious condition called "differentiation syndrome" may occur. If you experience symptoms such as fever, difficulty breathing, rash, dizziness or lightheadedness, rapid weight gain, or swelling of the arms or legs, you must contact your doctor immediately. Differentiation syndrome is caused by the rapid differentiation of leukemia cells and the release of inflammatory factors, and if not treated promptly, it can be life‑threatening. Your doctor will closely monitor your condition and may administer medications such as corticosteroids, and if necessary, temporarily interrupt gilteritinib until symptoms resolve. A patient information card is included in the package; be sure to carry it with you at all times and show it to all healthcare providers.

Other adverse reactions requiring urgent medical attention

In addition to differentiation syndrome, gilteritinib may cause two other serious adverse reactions that require immediate medical attention. The first is "posterior reversible encephalopathy syndrome," which presents as seizures, rapidly worsening headache, decreased alertness, confusion, blurred vision, or other visual disturbances. If these symptoms occur, your doctor will perform brain imaging, and if the diagnosis is confirmed, gilteritinib treatment will be stopped immediately. The second is "QT prolongation," an abnormality in the heart's electrical activity that can lead to irregular heartbeat, dizziness, fainting, or even an increased risk of sudden death. If you feel an irregular heartbeat, dizziness, or fainting, tell your doctor right away. Additionally, if you experience severe upper abdominal and back pain accompanied by nausea and vomiting (which may be signs of pancreatitis), you should also seek medical attention promptly.