What Causes Severely Flushed Skin?

Thank you. I am actually a physician myself, sidelined after AML. I underwent a T-cell depleted stem cell transplant 6 years ago. I am now experiencing many of the sequelae of my treatment, which included TBI. I have had fairly stable renal dysfunction until recently, when I developed microalbuminemia and hypertension. I was put on Olmesartan just a few months ago, which was at first very efficacious. Now my blood pressure varies greatly with diastolics as high as the low 90s. All that is background. I also have taken HCTZ for years for renal calcium leak and now take it in a combined Olmesartan 40/HCTZ 25 regimen. I also take Cialis 5 mg daily and Rapaflo 8 mg for BPH. I am experiencing chronic flushing now (skin red to a variable degree most of the day) that I think is temporally related to the Olmesartan. I also have a chronic tension type headache/dizzy feeling (which is unrelated to when my BP is elevated), and my visual acuity seems a bit reduced (as if I need a stronger prescription). The biggest concern is the flushing. I have had my serotonin levels checked, 5HIAA, and chromogranin A. The latter was elevated to around 35. However, I am on chronic PPI therapy, a situation well described to increase CGA by many multiples. There is also no reason to suspect carcinoid syndrome in the absence of any other consistent symptoms. I apologize for rambling, but do you have any explanation for the red face and hands? Is this a side effect that is too seldom to be reported? There is no associated pain in the hands to suggest erythromelalgia.