If a client has an allergy to iodine, what treatment should be avoided?

In cases of an allergy to iodine, the treatment that should be avoided is the seaweed facial. This is because seaweed, particularly certain types like kelp, contains iodine, which can trigger allergic reactions in sensitive individuals. Those with an iodine allergy should steer clear of any products containing seaweed to prevent the risk of an allergic response.

The other options, while they may include substances from marine sources, do not typically contain iodine in significant amounts or primarily consist of ingredients that are less likely to provoke an allergic reaction in individuals with iodine sensitivities. Therefore, it is essential to identify and avoid seaweed-based products to ensure the client's safety and comfort during aesthetic treatments.