What should be used for itching relief by patients undergoing external radiotherapy?

Using cornstarch for itching relief in patients undergoing external radiotherapy is advisable due to its properties that help manage moisture and friction, creating a soothing effect on the skin. Radiotherapy often leads to skin irritation and dryness, so applying cornstarch can absorb excess moisture and reduce irritation without causing further sensitization or unwanted reactions.

On the other hand, alcohol-based lotions can be quite irritating to sensitive skin that is already compromised due to radiotherapy, potentially exacerbating itching rather than alleviating it. Antihistamines may provide some relief from systemic allergic reactions but are not specifically useful for localized skin irritation associated with radiotherapy. Ice packs might provide temporary relief from discomfort, but they do not address the underlying issue of dry, irritated skin effectively, and cooling the skin excessively can lead to more problems.

Therefore, cornstarch stands out as the most appropriate choice for providing comfort to patients experiencing itching due to radiation treatment.