I get itchy redness with small pimples around my mouth every now and then what could this be ?

Many answers: Itchiness may mean that you may be allergic to something the area surrounding your mouth has been in contact with.The potential allergens range from food, juice , or even toothpaste but the skin rash may not occur until 2-3 days after the contact or as early as minutes after depending on the allergic mechanism. If you can't find the answer, you need to see a dermatologist.