Hi, welcome to the forum, your history is suggestive of that you may be having drug allergy to vitamin formulation. You may be hypersensitive to any component of the formulation. From your history it is suggests that you are intolerant to formulations of vitamin esp. if lactose or lactose like base is used.
You need to discontinue the vitamins and go for other brands having different components. See whether you are comfortable with the new drug. Adding of oral anti histamine and corticosteroids against prescription will help to subside the allergic reaction I suggest you to consult physician. Take care and regards.
it is possible you need to stop taking them until you can see you doctor to make sure don't take them anymore until you find out because the reaction could get worse each time you are expose to the allergen and become life threatening