Arnica is a daisy-like plant from which arnica oil can be extracted. Ointments containing arnica oil are widely available over the counter for treating skin conditions such as sunburn, bruises, healing wounds and eczema.

Many people who have used arnica ointment feel that it has helped reduce soreness and bruising after operations (including breast surgery). Patients have also found it has eased some of the discomfort that can occur in the skin during or immediately after radiotherapy, if the skin has become inflamed. However, it is important not to use arnica cream on broken skin as it can cause irritation.

Although there is no doubt that some people feel arnica has been very helpful in easing their skin soreness during cancer treatment (either after surgery or radiotherapy) the scientific trials that have been done, comparing the use of arnica with a placebo (an inactive cream), have not shown any improvement in wound healing.

Arnica ointment is safe to use, although if used repeatedly and to excess it can cause skin irritation and blistering. It is also relatively cheap and, although the scientific evidence is lacking, given that some people have said they find it has helped them, there would be no harm in giving it a try if you wanted to.