Both methods are effective for the treatment of AK's but Efudex is the "gold standard". It is not easy to use, but you do not have to become one of those pictures you mention in your question. I have patients use Efudex until they get a response, meaning until they start to get a little irritated and crusty. That may take 2 to 4 weeks or that may only take a few days depending on how sun damaged you are.
Once you start to react to the Efudex, stop. Do not continue to apply it or you will look like the horrible pictures. Once you stop the Efudex it will take about a week for your skin to calm down. If you still have a lot of AK's, then do it again, but for a little bit longer. This is a more gentle way of using Efudex to get to the same clinical endpoint without suffering.
