This is angiooedema of face. Your wife is definitly allergic to something. You have to use elimination method to identify the cause yourself and avoid it in future. Also you can get her IgE tested.

The condition is called angioedema and it's due to allergy. With homeopathic treatment she can get rid of this problem.

It is called angioedema. Many times it is difficult to find a particular object of allergy. And it is almost a goose chase. Even blood test will give list of 10-15 items causing allergy. If you remove those objects some new will come. The ideal way is to correct the body's internal mechanism which gives such altered reaction. And it is possible by homeopathic medicine. Just consult a good homeopathic Doctor of your choice and trust and take proper homeopathic treatment. Note: don't take random suggestions or company made mixtures.

For  the food allergy  test do immnuoglbin E  igE test .Along  with  this  you  take  homeopathic treatments ,this is curable .

Many persons have urticaria or allergic reaction to peanuts . She need to take proper to correct this . It requires long term treatment till then avoid peanut.

It can be food allergy. So you can do Blood test for IgE antibodies to specific foods.