Took arnica homeopath first time yesterday and woke up the morning itchy, upset stomach and few rashes. could it be arnica and does it have nuts in it?

I don't: See nuts. But all your symptoms could be due to the med. Stop taking and talk to your doctor

Arnica may do that: Arnica does not contain nuts. It is usually used as a dilute cream or oral medicine. It is toxic, especially in pure or more concentrated forms. It can cause allergies and stomach problems. In view of your reaction, you should discontinue it. If OTC allergy medicines do not relieve your symptoms, call your physician

Arnica: Does not have nuts as active or inactive ingredient. It sounds like you are having an allergic reaction to it however. Take loratidine or cetrizine and stop taking the arnica.