Topical Chemotherapy — Cream: Not a Drip, Not an Injection

Very unlikely. The cream stays mostly on the skin surface rather than entering the bloodstream in significant amounts, so hair loss, nausea and systemic fatigue are not expected. What you will notice is a local skin reaction — redness, flaking and crusting in the treated area. This is expected and means the medicine is working. Call your team the same day if the reaction spreads beyond the treated zone, the skin is oozing, or you develop fever.

Your oncologist will prescribe a specific course length based on the condition being treated and how your skin responds. Do not stop early because the skin looks bad — that reaction is usually the treatment working at its peak. Do not extend beyond what was prescribed without speaking to your team. Your monitoring appointments are the right time to review whether any change is needed.

In most cases, yes. Redness, crusting and peeling can look alarming, particularly on the face, and the reaction often peaks before the course ends. After finishing, the skin heals and usually looks clearer than before, because the abnormal cells have been destroyed. Contact your team if the reaction spreads well beyond the treated area, the skin is oozing or extremely painful, or you develop a fever — those need same-day review.

No. Fluorouracil is not safe in pregnancy even when applied to the skin, because some is absorbed into the bloodstream. Tell your oncologist before the prescription is written if you are pregnant, could become pregnant, or are breastfeeding. If you are of childbearing age, your team will discuss contraception. If you become pregnant while using the cream, stop immediately and contact your team and your obstetrician the same day.

Yes. A glove protects the skin on your hands from absorbing the medicine. If the cream contacts ungloved fingers, wash thoroughly with soap and water. Apply the glove before opening the tube, not after. Dispose of used gloves carefully and keep the cream out of reach of children and other household members, since incidental contact with healthy skin should be avoided.

Your oncologist will review the treated area after the skin has had time to heal, to assess whether the abnormal cells were adequately treated. Some people need a repeat course or a different approach if the response is incomplete. Ongoing sun protection matters more after treatment than before — skin in that area has already shown it is vulnerable to sun damage, and consistent protection reduces the risk of new lesions developing.