Leqembi (injection)

Lecanemab is used to treat adults with Alzheimer's disease.

Lecanemab may also be used for reasons not mentioned in this medication guide.

Lecanemab can cause temporary swelling or bleeding in the brain that usually goes away over time. This condition may not show any symptoms but can be serious. Call your doctor if you experience headaches, dizziness, nausea, confusion, difficulty walking, seizures, or changes in vision.

Lecanemab can cause a condition called Amyloid Related Imaging Abnormalities or "ARIA," which is temporary swelling or small spots of bleeding in the brain that usually goes away over time. Your doctor may perform an MRI of your brain before and during your treatment with lecanemab. Ask your doctor about your risk.

It is not known if lecanemab will harm an unborn baby. Tell your doctor if you are pregnant or plan to become pregnant.

Ask a doctor if it is safe to breastfeed while using this medicine.

Get emergency medical help if you notice signs of an allergic reaction: hives; trouble breathing; swelling of your face, lips, tongue, or throat.

Some side effects may happen during the injection. Tell your medical caregiver if you feel dizzy, nauseous, light-headed, itchy, sweaty, or have a headache, flu-like symptoms, fever, or vomiting; chest tightness, fast or slow heartbeats, pounding heartbeats, back pain, trouble breathing, or swelling in your face.

Common side effects of Leqembi may include:

• ARIA with symptoms or with signs that show up on an MRI;
• infusion-related reactions; or
• headache.

This is not a complete list of side effects, and others may happen. Call your doctor for medical advice about side effects. You can report side effects to the FDA at 1-800-FDA-1088.

Lecanemab is injected into a vein by a healthcare provider.

This medicine is injected slowly over 1 hour every 2 weeks.

You may be given other medications to help prevent serious side effects or allergic reaction.

Store this medicine in the refrigerator in the original container, do not freeze or shake.

Call your doctor for guidance if you miss an appointment for your Leqembi (injection).

In a medical setting, an overdose would be treated quickly.

Follow your doctor's instructions regarding any restrictions on food, drinks, or activities.

Tell your doctor about all the other medicines you are taking, especially those for treating or preventing blood clots, including aspirin.

Other drugs may influence how lecanemab works, including prescription and over-the-counter medicines, vitamins, and herbal products. Make sure to inform your doctor about all the other medicines you are using.

Find detailed information on biosimilars for this medication.