Some of the meds have some interesting effects.
They use some blood pressure meds to treat anxiety, ptsd, and nightmares.
There is a new investigational antipsychotic (RP5063) that also happens to be good for pulmonary arterial hypertension.
I don’t know what it could be, but with your family history, probably a good call by the doctor.
I’m happy for you that you don’t have sz, anubis.
Twelve years without an ap probably rules out sz anyway. Your posts would serve well for anyone who is the same position as yourself trying to make sense of what is happening to them. Is your psychiatrist aware that you are suffering with a psychosomatic illness? What is her verdict? Does she intend to give you a low dose ap to steady the anxiety and weight loss?
Keep talking if it is helping you and let us know how it goes. Take care of yourself.
Thanks a lot @firemonkey for your 2 great articles. I remembered now that my psychiatrist once talked to me a long time ago about somatic symptoms disorder but she wasn’t sure because normally, as it is written in the Wikipedia article, somatic symptoms disorder cannot be cured by medications, and I was successfully cured by it. This is why I think I may have something else too. And I really like your other article about this situation because it makes me think that I could also be a bipolar.
I will surely talk to my psychiatrist about that! Thanks a lot!!! 
From the Wikipedia page about somatic symptoms disorder:
The patient must also be excessively worried about their symptoms, and this worry must be judged to be out of proportion to the severity of the physical complaints themselves
This doesn’t relate to me at all. My worries weren’t out of proportion because my physical condition was very severe and dangerous. The local hospital once urgently transferred me to a specialized hospital for a dangerous arrhythmia problem. It was a 2 hours ambulance road trip just for me. In 2006, I lost so much weight so rapidly that I was sent to see a gastroenterologist in only 2 days. I also spent many nights at the emergency room because of arrhythmia problems.
I guess this eliminates the somatic symptoms disorder diagnosis. I don’t know what my psychiatrist think about that. She always said that my physical condition was really severe and that I was really suffering. But I know that the cause is not physical. But still my worries were not exaggerated.
Have you checked your thyroid levels? And also liver status? Thyroid problems can do that to you. Irregular heartbeat and severe weight loss, pains, tiredness or hyperactivity.