This medication is used to treat bladder cancer. Erdafitinib belongs to a class of drugs known as kinase inhibitors. It works by slowing or stopping the growth of cancer cells that have a certain type of abnormal gene ("FGFR").

Read the Patient Information Leaflet if available from your pharmacist before you start taking erdafitinib and each time you get a refill. If you have any questions, ask your doctor or pharmacist.

Take this medication by mouth with or without food as directed by your doctor, usually once daily. Swallow the medication whole. If you vomit after taking erdafitinib, do not take another dose on the same day. Wait until the next day to take your regular dose.

Use this medication regularly to get the most benefit from it. To help you remember, take it at the same time each day.

The dosage is based on your medical condition and response to treatment. Do not increase your dose or use this drug more often or for longer than prescribed. Your condition will not improve any faster, and your risk of serious side effects will increase.

Since this drug can be absorbed through the skin and lungs and may harm an unborn baby, women who are pregnant or who may become pregnant should not handle this medication or breathe the dust from the tablets.

Nausea, vomiting, mouth sores/pain, change in how food tastes, abdominal pain, diarrhea, constipation, loss of appetite, weight loss, tiredness, dry mouth/skin, or muscle/joint pain may occur. If any of these effects last or get worse, tell your doctor or pharmacist promptly.

Temporary hair loss may occur. Normal hair growth should return after treatment has ended.

People using this medication may have serious side effects. However, you have been prescribed this drug because your doctor has judged that the benefit to you is greater than the risk of side effects. Careful monitoring by your doctor may decrease your risk.

Tell your doctor right away if you have any serious side effects, including:

• nail problems (such as nail pain/bleeding, lifting off the nail bed, changes in color or texture, infected skin around the nail)

Eye problems commonly occur, but can also be serious. To prevent or treat dry eyes, use lubricating eye drops/gels/ointments every 2 hours while you are awake. Tell your doctor right away if you develop blurred/decreased vision or loss of vision.

This medication may cause your blood phosphate levels to increase. Your doctor will check phosphate levels regularly during treatment, and may adjust your dose of erdafitinib. You may be asked to change your diet to limit the amount of phosphate your body absorbs. You may also be prescribed other medication to treat high phosphate levels. Tell your doctor right away if you have symptoms of high phosphate levels, such as muscle cramps, numbness/tingling around the mouth.

Erdafitinib may make you develop a skin problem called hand-foot syndrome. To help prevent this, protect your hands and feet from heat or increased pressure. Avoid activities such as using hot dishwater, taking tub baths, jogging, long walks, or using garden or household tools such as screwdrivers. Symptoms may include pain, swelling, redness, blisters, or numbness of the hands/feet. Your doctor may prescribe medication (such as balm) to help with symptoms. If symptoms affect your usual activities, get medical help right away.

For women of childbearing age, this medication may affect your ability to have children. Ask your doctor for more details.

A very serious allergic reaction to this drug is rare. However, get medical help right away if you notice any symptoms of a serious allergic reaction, including:

• rash
• itching/swelling (especially of the face/tongue/throat)
• severe dizziness
• trouble breathing

This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.

In the US - Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088 or at www.fda.gov/medwatch.

In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.

Before taking erdafitinib, tell your doctor or pharmacist if you are allergic to it; or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.

Before using this medication, tell your doctor or pharmacist your medical history, especially of:

• eye or vision problems
• kidney disease
• liver disease

Before having surgery, tell your doctor or dentist about all the products you use (including prescription drugs, nonprescription drugs, and herbal products).

Older adults may be more sensitive to the side effects of this drug.

Since this drug can be absorbed through the skin and lungs and may harm an unborn baby, women who are pregnant or who may become pregnant should not handle this medication or breathe the dust from the tablets.

Tell your doctor if you are pregnant or plan to become pregnant. You should not become pregnant while using erdafitinib. Erdafitinib may harm an unborn baby. Your doctor should order a pregnancy test before you start this medication. Men and women using this medication should ask about reliable forms of birth control during treatment and for 1 month after the last dose. If you or your partner becomes pregnant, talk to your doctor right away about the risks and benefits of this medication.

It is unknown if this medication passes into breast milk. Because of the possible risk to the infant, breastfeeding is not recommended while using this medication and for 1 month after the last dose. Consult your doctor before breastfeeding.

Drug interactions may change how your medications work or increase your risk for serious side effects. This document does not contain all possible drug interactions. Keep a list of all the products you use (including prescription/nonprescription drugs and herbal products) and share it with your doctor and pharmacist. Do not start, stop, or change the dosage of any medicines without your doctor's approval.

Other medications can affect the removal of erdafitinib from your body, which may affect how erdafitinib works. Examples include rifamycins (such as rifabutin, rifampin), St. John's wort, drugs used to treat seizures (such as carbamazepine, phenytoin), among others.

If someone has overdosed and has serious symptoms such as passing out or trouble breathing, call 911. Otherwise, call a poison control center right away. US residents can call 1-800-222-1222. Canada residents can call 1-844-764-7669.

Do not share this medication with others.

Lab and/or medical tests (such as eye exams, blood phosphate levels, complete blood count, kidney/liver function) should be done while you are taking this medication. Keep all medical and lab appointments.

If you miss a dose, take it as soon as you remember. If you don't remember until the next day, skip the missed dose. Take your next dose at the regular time. Do not double the dose to catch up.

Store at room temperature away from light and moisture. Do not store in the bathroom. Keep all medications away from children and pets.

Do not flush medications down the toilet or pour them into a drain unless instructed to do so. Properly discard this product when it is expired or no longer needed. Consult your pharmacist or local waste disposal company.