Extremely Dry, Cracking Skin — on Cancer Tablets

Skin reactions are a side effect of how targeted therapy acts on skin cells — not a reliable indicator of whether it is working against the cancer. Some research has observed an association between certain skin reactions and response in specific cancer types, but this is not consistent across drugs or patients, and it is not used clinically to judge whether treatment is effective. Response is measured through imaging and tumour markers, not skin changes. Do not read your skin as a sign of how the cancer is responding.

For most people, a thick over-the-counter emollient — petroleum jelly, a fragrance-free body cream, or a urea-based heel cream — is the right starting point and genuinely effective when used consistently. The key is applying it often, and immediately after washing. Prescription-strength treatments are added when over-the-counter options are not keeping pace with the dryness, or when the skin needs a medical assessment. Ask your pharmacist to suggest a suitable product, and tell your oncology nurse what you are using at your next visit.

Fingertip cracks are one of the most functionally limiting skin effects of targeted therapy, and your oncologist needs to know if they are affecting your ability to work or manage daily tasks. In the short term, keeping each crack covered with a small wound closure strip or fingertip bandage reduces pain and protects against infection. Thick petroleum jelly applied under thin cotton gloves overnight can help prevent new cracks from opening. If any crack is deep, very painful, or showing warmth or redness, call your team that day rather than waiting for your next appointment.

Chemotherapy skin changes often follow the treatment cycle — appearing and then improving in predictable windows around each dose. Targeted therapy skin effects tend to build over time and persist throughout treatment, worsening progressively if not managed. The nature of the change also differs: targeted therapy more typically causes deep dryness, fissuring, and sometimes an acneiform rash on the face and chest. The home management approach overlaps — moisturise consistently, protect the skin barrier, report signs of infection — but the timeline and pattern are different enough that it is worth telling your team exactly what you are experiencing.

Do not stop targeted therapy on your own without speaking to your oncologist first. Stopping abruptly may affect how well the treatment controls the cancer, and your oncologist needs full information about how severe the skin reaction is before making that decision. If the skin is severely painful, infected, or stopping you from functioning, call your team today — that is the right route to getting a dose pause or adjustment properly assessed, not self-stopping. Your team can also arrange faster support than a routine appointment when the situation needs it.