Symptoms may be exacerbated with prolonged sitting, prolonged standing, alcohol, heat, exercise, or eating a large meal.Up to one-third of POTS patients experience fainting for many reasons, including but not limited to standing, physical exertion, or heat exposure. POTS patients may also experience orthostatic headaches. Some POTS patients may develop blood pooling in the extremities, characterized by a reddish-purple color of the legs and/or hands upon standing. 48% of people with POTS report chronic fatigue and 32% report sleep disturbances. Other POTS patients only exhibit the cardinal symptom of orthostatic tachycardia. Additional signs and symptoms are varied, and may include excessive sweating, lack of sweating, heat intolerance, digestive issues such as nausea, indigestion, constipation, and diarrhea, post-exertional malaise, coat-hanger pain, brain fog, and syncope or presyncope. Brain fog
One of the most disabling and prevalent symptoms in POTS is "brain fog", a term used by patients to describe the cognitive difficulties they experience. In one survey of 138 POTS patients, brain fog was defined as "forgetful" (91%), "difficulty thinking" (89%), and "difficulty focusing" (88%). Other common description was "Difficulty processing what others say" (80%), Confusion (71%), Lost (64%), and "Thoughts moving too quickly" (40%).
Postural orthostatic tachycardia syndrome (POTS) is a condition characterized by an abnormally large increase in heart rate upon standing. Symptoms may include lightheadedness, brain fog, blurred vision, weakness, fatigue, headaches, heart palpitations, exercise intolerance, nausea, diminished concentration, tremulousness (shaking), syncope (fainting), coldness or pain in the extremities, chest pain and shortness of breath. Other conditions associated with POTS include Ehlers–Danlos syndrome, mast cell activation syndrome, irritable bowel syndrome, insomnia, chronic headaches, chronic fatigue syndrome, and fibromyalgia. POTS symptoms may be treated with lifestyle changes such as increasing fluid and salt intake, wearing compression stockings, gentler and slow postural changes, avoiding prolonged bedrest, medication and physical therapy. The causes of POTS are varied. POTS may develop after a viral infection, surgery, trauma or pregnancy. It has been shown to emerge in previously healthy patients after COVID-19. Risk factors include a family history of the condition. A POTS diagnosis in adults is characterized by an increased heart rate of 30 beats per minute within ten minutes of standing up, while accompanied by symptoms. This increased heart rate should occur in the absence of orthostatic hypotension (>20 mm Hg drop in systolic blood pressure) to be considered POTS. A spinal fluid leak (called spontaneous intracranial hypotension) may have the same signs and symptoms as POTS and should be excluded. Prolonged bedrest may lead to multiple symptoms, including blood volume loss and postural tachycardia.