Hi, there. Welcome to NeuroTalk.

I am going to bring up your lisinopril. I really cannot address your original question but I can tell you that this drug causes all sorts of grief in some people.

It is derived from snake venom. It dilates blood vessels, by blocking a biogenic amine from breakdown, in the body called bradykinin. Some people are sensitive to this, and get all sorts of "allergic appearing symptoms", but these are not mediated by histamine, but the bradykinin instead. The heat, rush feeling could be a sudden dilation happening. The itching on the hands also may be due to vasodilation causing a prickling sensation.
The throbbing you feel could also be related.

I was on an ACE inhibitor and finally lisinopril for over 10 yrs. I had the most awful attack of this reaction which is called acquired angioedema, finally, because as it built up over time I thought it was allergies etc. I suggest you discuss with your doctor a change of medication. Do not accept an ACE drug...they all cause this. Lisinopril in that family also is lipophilic and enters the brain more than others. You don't mention a dry cough but that is also a symptom, and/or swelling of various body parts, which may come and go.

It took several weeks for my reaction to taper off. My doctor also thought I had a drug induced lupus event, going on with the swelling and burning, and difficulty breathing that the lisinopril caused. I used to take it at night, and by midnight I'd wake up in a total panic, thinking I was going to die.

I am now on a small dose of beta blocker and have my life back.
All the alarming effects that the drug was causing me are gone finally. My doctor had never had a person with this reaction, but she recognized it because of a recent continuing medical ed course she took for relicensure. So some doctors "won't believe"
you. Just be firm and ask for a new blood pressure drug, not in the ACE family, and see what happens over the next 6mons.

Many of your symptoms may stop. But you won't know unless you do it.

Also with chronic Nexium use, you may become low in nutrients that depend on stomach acid for normal absorption.
B12, folate, calcium, magnesium, iron and zinc. So get tested for Vit D and B12 levels. Your B12 should be at 400pg/ml minimum and is not "normal" at the old lab ranges that still are used by doctors.

This is our B12 thread:
http://neurotalk.psychcentral.com/thread85103.html
The first post has a link to a very good YouTube describing how
low B12 sneaks up on people and is missed by doctors entirely!
Please view that video...it may save your life.

You can read more on acquired angioedema and also hereditary
angioedema. There is quite a bit of new information on the net from medical schools who are now teaching this to new students. (this wasn't recognized until the 1970's). Hence many doctors do not even know about it! (I am lucky that mine did!)