I agree with B, it's the sulphites in the wine, regardless of the color.
Although sulphites do not cause a true allergic reaction, sulphite-sensitive people may experience similar reactions as those with food allergies. Those who have asthma are most at risk to sulphite sensitivity and other forms of sulphite reactions.
When someone comes in contact with an allergen or sulphite, the symptoms of a reaction may develop quickly and rapidly progress from mild to severe. The most severe form of an allergic reaction is called anaphylaxis. Symptoms can include breathing difficulties, a drop in blood pressure or shock, which may result in loss of consciousness and even death. A person experiencing an allergic reaction may have any of the following symptoms:
Flushed face, hives or a rash, red and itchy skin
Swelling of the eyes, face, lips, throat and tongue
Trouble breathing, speaking or swallowing
Anxiety, distress, faintness, paleness, sense of doom, weakness
Cramps, diarrhea, vomiting
A drop in blood pressure, rapid heart beat, loss of consciousness.
Currently there is no cure for food allergies or sulphite sensitivity. The only option is complete avoidance of the specific allergen.
http://www.hc-sc.gc.ca/fn-an/securit/allerg/fa-aa/allerge...