Here are some things I have successfully used over the years for hives.
1. Vitamin C internally, if you are not allergic to corn or have a hypoallergenic brand.
2. Orange juice (or lemon juice in water) internally, if you are not allergic to citrus.
3. Apis mellifica 30c or Rhus Tox 30c is a great homeopathic remedy for some types of hives.
4. Chamomile works for some people, due to diminishing the histamine response. But some people are allergic to it, especially if allergic to ragweed.
5. I have used 1 teaspoon of baking soda dissolved completely in water internally in emergencies and this has helped sometimes. But do not use it too often as it is too high in sodium and should not be used if on a sodium restricted diet.
You can also apply baking soda in a paste, made with water, directly to the hives. But remove immediately if it makes itching or swelling worse.
6. Potatoes boiled in water with the skins on (put in very little salt) and drink the water. This is high in potassium and can sometimes stop hives or a reaction.
Avoid cayenne or hot sauces or hot peppers because this can speed up the allergen going through your system, increase it and make the reaction/hives worse.
BUT... you need to go to the doctor for hives and have emergency medication on hand at all times. I would use the natural things along with the medications on your doctors OK, but not the baking soda as it will antidote or neutralize most medications.