When my psoriatic arthritis first flared up severely 3 years ago, I experienced a LOT of palpitations. That was long before I was diagnosed. My family doctor had me wear a holter monitor for 24 hours. It recorded the palpitations, but they said they weren't anything to worry about. I've had small numbers of palpitations all my life, so they normally don't worry me. But they became very frequent for a few weeks when my inflammation first kicked up badly.
Hope you feel better soon!
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Psoriatic spondylitis for just 3 years, already on disability. Failed with anti-TNF's and methotrexate; can't take NSAIDS; not on any regular pain meds. On the autoimmune protocol of the Paleo diet, with pretty good results so far. Also have to avoid high-oxalate foods.