Arnica cream v gel.

Hi,

Thanks to this forum I am going to get some arnica tablets for when I have my mastectomy. I was also advised to get cream aswell. However, I read somewhere that if used for too long it can irritate the skin. How long is too long? I was going to use it 3 times daily 1 week prior to the op and 2 weeks after, like the tablets.

Also is there any difference between the effects of the gel as opposed to cream, as the gel seems to be favoured?

Thank you.