Ive had a few 2mm moles on my arm right next to each other sometimes get what seems like eczema on them. had this before on a different tiny mole. moisturizing cream for a few days clears it up. eczema patches on arm as well cause? meyerson nevus?

Likely just eczema: Any mole that changes from time to time should be examined by a dermatologist, but it sounds like you have dry skin or generalized eczema on your arms and then sometimes get it on top of the moles as well. A Meyerson nevus does get an eczema type reaction, but more likely to be a halo type around the mole and larger, over 1 cm. Routine use of lotion is a must for those with eczema or atopic derm.