A woman holds a tube of fluorouracil cream in her hands, and her reflection looks back at her from the cream tube surface.

Efudex: Um, When Am I Done?

Prescriptions are straightforward and by-the-book. Your doctor or pharmacist provides a quick explanation of how much and how often to take it and may offer up advice on the best time to take it - before, with, or following a meal. As long as you follow the provided instructions, you will likely have few questions since everything has been laid out very neatly for you. Your little bottle with the childproof cap even has an efficiently printed label clearly showing you when you need to stop taking your medication. Efudex, also a prescription medication, has the unfortunate distinction of not being so cut-and-dry.

How long should I use Efudex cream?

When you are handed your tube of Efudex, also known as fluorouracil, the label will display your dermatologist’s instructions. They, too, are straightforward and printed according to your doctor’s recommendations. You may have been told to “apply a thin layer twice a day for 4 weeks.” In some cases, patients might be instructed to “apply cream once daily for 6-8 weeks.” This, unfortunately, is where things begin to get a little hazy. It seems no two patients are told exactly the same thing. It is certain that no two patients will experience the same pacing of results.

How do I know when to stop?

The big question for most people treating actinic keratosis with Efudex is, “How do I know when to stop?” I know it was one of my first questions as the effects began to take hold. When the redness, burning, and itching continued to ramp up, I wanted to know when in the world it would ever end. You see, Efudex is one of those medications that actually makes things infinitely worse before it makes things better. This particular characteristic alone is one of the reasons many patients decide along with their physicians not to explore it as an option. The fear of the unknown and the fear of not knowing when enough is enough can be overwhelming.

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Recognizing the erosion stage

If you are fortunate enough to have a dermatologist or general practitioner who takes the time to have a heart-to-heart before leaving the office, you may hear about the erosion phase of treatment. This, friends, is the magic word. When your skin has reached the erosion stage, you are done. Believe me, you will have been mentally done long before the erosion phase hits, but the physical manifestation of erosion is your sign to stop applying the cream.

Some of us are not as fortunate and don’t leave the doctor’s office feeling prepared for what is to come. Erosion is never mentioned therefore we have no idea how to watch for signs to stop applying the cream. I feel pretty safe in assuming that the mention of the word “erosion” in relation to our skin is terrifying for all of us whether the doctor brings it up or we stumble across it in a 1:00 am online search later at home.

Erosion, in simplest terms, is the point in which the cream has done all it can for your actinic keratosis. Some of us reach this stage in two weeks, others in 4-6. Quite honestly, there are some patients who take even longer to reach the end of treatment. There are some patients with extensive sun damage who react much more rapidly and reach the erosion stage before the prescribed 4 weeks on their tubes.

What does the erosion stage of Efudex look like?

April using Efudex, during erosion stage

You will know you have reached the erosion phase of treatment when your skin begins to crack open and weep clear fluid. Depending upon the patient, some areas may even bleed slightly once the cream has fully absorbed and the skin has dried out. At this point in treatment, it becomes extremely difficult to even apply the cream, and the slightest touch could send you into orbit. It is now you should make every effort to contact your prescribing physician and allow him/her to guide you in stopping or continuing a little longer. I was prescribed a 21-day course of treatment and reached erosion on day 17. A quick stop by my doctor’s office was enough to let me know I was indeed done and ready to begin healing.

Reach out to your doctors and nurses

While we can’t know from the outset when we will reach the end of treatment, we can use the advice of doctors and other Efudex users to have a clearer idea of when to stop applying the cream. No one should have to leave the doctor’s office depending solely on the instructions on the tube - Efudex is so much more than a pill. Rely on your gut to help you ask questions, and rely on your doctor or nurse to give you guidance. For those difficult days in between day one and erosion, rely on us. We have been there, and we can hold your hand.

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