Rash from tamoxifen: what to know

A rash can appear as redness, itching, raised patches, or small spots. It may be related to tamoxifen, another medicine, an infection, or an unrelated skin condition. Timing matters: tell the clinician when it began, where it started, whether it is spreading, and whether you recently began or changed a medicine, cream, supplement, or detergent.

Tamoxifen is a hormone medicine used in some cancer treatment plans and in [Risk-Reducing Endocrine Therapy](/treatments/risk-reduction-and-prevention/risk-reducing-endocrine-therapy/). A rash does not by itself show that treatment is working or failing. The clinician may examine the skin and decide whether treatment should continue, pause, or change.

Contact your oncology or prescribing team as soon as you notice a new rash. Send a clear photograph if the team accepts images, and keep a list of all medicines and products used on the skin. Do not stop tamoxifen or restart it after a break without medical advice.

Use gentle, fragrance-free skin care and avoid scratching, hot showers, and newly introduced products until you have guidance. A clinician may recommend a suitable treatment after checking the rash and your other medicines. Learn more about [Tamoxifen](/materials/tamoxifen/) and [Hormone Therapy for Cancer](/treatments/systemic-therapy/hormone-therapy-for-cancer/).

Get emergency help for swelling of the lips, tongue, face, or throat; wheezing or breathing difficulty; faintness; widespread blistering or peeling; painful skin; sores in the mouth or eyes; or a rash with fever. These features need prompt assessment rather than home treatment.

Could this rash be caused by tamoxifen or another product? Should I continue the next dose while it is assessed? What symptoms require emergency help? Which creams or antihistamines are suitable with my medicines? How will you decide whether treatment needs changing?