Medication | Dose | Mechanism of action | Side effects | Notes |
---|---|---|---|---|
Propranolol | 10–20 mg orally four times a day | β-adrenergic receptor antagonist | Bradycardia, bronchospasm and hypotension | May help in lower doses and is not well tolerated in higher doses |
Midodrine | 2.5–10 mg orally every 4 hours or three times a day | α1-adrenergic receptor agonist | Scalp paraesthesias, piloerection, urinary retention and supine hypertension | Do not take 4 hours before bedtime to avoid supine hypertension |
Fludrocortisone | 0.05–0.2 mg/day orally or every other day | Expands blood volume through renal reabsorption of sodium | Hypertension, hypokalaemia and oedema | Monitor for low serum potassium |
Pyridostigmine | 30–60 mg orally three times a day | Acetylcholinesterase inhibitor | Diarrhoea and abdominal cramping | It helps but is not too potent by itself |
Clonidine | 0.05–0.2 mg twice daily | Central sympatholytic α-2 receptor agonist | May cause sedation and hypotension | Decreases plasma norepinephrine; can lead to rebound due to short half-life |
Methyldopa | 125–250 mg orally twice daily | Central sympatholytic (false neurotransmitter) | Sedation and hypotension | Longer half-life, so often better tolerated |
Desmopressin (DDAVP) | 0.2 mg orally as needed | Acute blood volume expansion | Water retention and hyponatraemia | Carefully monitor for hyponatraemia |
Ivabradine | 5–7.5 mg once or twice daily | Funny channel blocker | Bradycardia | No randomised trials for POTS |
Modafinil | 100 mg orally twice daily | Stimulant | May exacerbate tachycardia in some patients | Approved for sleep disorders but may help with concentration |
Medications commonly used to treat the symptoms of postural tachycardia syndrome (POTS). These medications can be used alone or in combination.
POTS, postural tachycardia syndrome.