Psoriasis is a chronic skin condition involving red patches with silvery scales. The
Essential Oils Desk Reference
suggests Roman chamomile and tea tree essential oils for psoriasis. The book also suggests this blend:
2 drops patchouli
2 drops Roman chamomile
2 drops lavender
2 drops tea tree
Dilute at least 50/50 with carrier oil (more if you tend to be sensitive) and spot test before applying to a large area.
Another suggestion from
Healing With Aromatherapy
for a psoriasis flare-up is to drink two to three cups of licorice root decoction a day and use some of the decoction as a compress (caution: do not use licorice root if you have high blood pressure). To make a decoction, simmer one teaspoon licorice root per cup of water for 20 minutes.
Also, I've heard many natural health practitioners suggest that skin conditions are a sign of an overloaded liver. You might want to consider working with a professional for a liver cleanse.