Hi - Hmmm...sorry this is happening to you!
So, what you want is a blend with both anti-inflammatory and anti-microbial properties. Concurrently, herbs and/or dietary changes supporting liver function are recommended.
This would be the best, and easiest, remedy in terms of the oils: Our Soothing Skin Extra
blend, with 'Benchmark' Thyme added
...using 20 drops of Thyme per ounce of the Soothing Skin.
You can order the smallest bottle of this Thyme - what we consider the MOST broad-spectrum - yet safe for topical application - essential oil available - and remove the 'euro-dropper' insert in the bottle. Then use a pipette or glass eye dropper to count these drops into the Soothing Skin.
Having the Benchmark Thyme around is nice, because it serves all purposes - and possibly more effectively - as Tea Tree.
Oh, and search for Schizandra Berry online. I personally take about a heaping tablespoon per day when I feel it necessary. It's very valuable for liver/skin cleansing and function. According to most research, there's something in your diet or environment that's causing the hives, though I expect work with your naturopath will uncover the source of this for you.
Hope this helps!