Although not dangerous, cold allergy or Cold Utricaria can cause symptoms of a rash such as redness, itching, and swelling which can interfere with daily activities. Cold allergies usually appear for a moment when a person is exposed to cold air/water directly. It can also occur due to drastic changes in temperature, such as in the morning. 

You don't have to take medication to treat cold allergies, however, you can take treatments to prevent or reduce the symptoms, such as:

1. Avoid cold air.
2. Protect the skin from sudden changes in temperature. For example, dip your hands in the water before swimming to see the skin reaction.
3. Avoid cold drinks and food to prevent the throat from swelling.

Source: halodoc.com