Facial symptoms (eye/nose watering, flushing) can be related to cluster headache.
POTS (Postural orthostatic tachycardia syndrome) – more common in females. Orthostatic tachycardia (NOT hypotension), dizziness, chest pain, palpitations, headaches, dyspnoea. Sometimes bluish red discolouration in lower limbs. No known cause, can have sudden onset in previously fit individuals. Associated with Ehlers Danlos (venous return problem?). Can be debilitating, associated with chronic pain, sleep problems, GI symptoms. Can improve over time. Diagnosis – heart rate increases by 30 beats per minute (bpm) or more (40bpm in those aged 12-19) after 10 minutes of standing, or if it increases to more than 120bpm. Consider treatment with beta blocker, fludrocortisone, SSRI.
Phaeochromocytoma can cause headache and sweating, but anxiety and palpitations should be prominent, with hypertension (or at least orthostatic hypotension).