Starting xolair tomorrow for chronic hives, given once a month, how long does this treatment usually last?

Rule of thumb: If you respond, you should get better in less than 2 months. There is no certain rule as to when to stop but 6 months would be what most would do once one has responded. I would stop the treatment if no response after 3 months.

Possibly a year or 2: Chronic hives can stop on their own any time. The fact that you live in NC and have IBS symptoms, makes it important that a Alpha gal and total IgE level be done before starting the Xoliar since Alpha gal meat allergy can present with IBS symptoms and with additional itchy tick bites progress to hives. Symptoms happen 4-6 hours after eating any beef or pork products, make it difficult to associate