Yes, they can be stress-related.
They are usually a response to a food or medication, but can also be caused by direct skin contact with something or exposure to cold or heat.
Emotional upsets can be the primary trigger of hives.
Mind-body techniques like hypnotherapy may be helpful in preventing chronic hives.
Antihistamines will often relieve acute episodes but are less successful with chronic hives and, because they are a suppressive treatment, may contribute to persistence of the disorder.
Try using quercetin instead. It works by stabilizing the membranes of cells that release histamine. This brings inflammatory and allergic reactions under control.
You can buy quercetin products in health-food stores.
The best form is a coated 400 mg tablet, taken twice a day between meals.
It can take six to eight weeks of continuous use for quercetin to build up to therapeutic levels in the body.
To soothe the itching of hives, try cornstarch or colloidal oatmeal added to bath water.