Before using fluorouracil, tell your doctor or pharmacist if you are allergic to it; or to flucytosine; or to capecitabine; or if you have any other allergies. This product may contain inactive ingredients (such as peanut oil found in some brands), 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: a certain enzyme deficiency (dihydropyrimidine dehydrogenase - DPD), red/irritated/infected/open sores on skin.

This medication may make you more sensitive to the sun. Limit your time in the sun. Avoid tanning booths and sunlamps. Use sunscreen and wear protective clothing when outdoors. After using fluorouracil cream, wait 2 hours before applying sunscreen or moisturizer to the treated area. Do not use other skin products including creams, lotions, medications, or cosmetics unless instructed by your doctor to do so. Tell your doctor right away if you get sunburned or have skin blisters/redness.

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

This medication must not be used during pregnancy. It may harm an unborn baby. Discuss the use of reliable forms of birth control with your doctor. If you become pregnant or think you may be pregnant, tell your doctor right away.

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. Consult your doctor before breastfeeding.