Pharmacologic treatments for postural tachycardia syndrome
| Therapy | Dosage | Pathologic mechanism addressed | Potential drawbacks | Comments |
|---|---|---|---|---|
| Blood volume expanders | ||||
| Fludrocortisone | 0.05–0.1 mg twice daily | Hypovolemia | Hypokalemia, hypertension, fatigue, headache, fluid retention, edema | |
| Desmopressin | 0.1–0.2 mg 3 times daily | Hypovolemia | Hyponatremia, headache, edema | Only for occasional use; must monitor blood sodium |
| Erythropoietin | 2,000–3,000 IU subcutaneously 1–3 times per week | Hypovolemia | High cost, requires injection, risk of vascular complications | Reserved for patients with symptoms refractory to more common treatments |
| Heart rate-lowering agents | ||||
| Propranolol | 10–20 mg 3–4 times daily | All | Hypotension, fatigue, drowsiness, wheezing | Not well tolerated at higher dosages |
| Ivabradine | 5–7.5 mg twice daily | All | Palpitations, headache, dizziness, constipation | |
| Central nervous system sympatholytics | ||||
| Clonidine | 0.05–0.2 mg twice daily | Hyperadrenergic | Mental clouding, fatigue, drowsiness, constipation | Can be associated with rebound hypertension and tachycardia |
| Methyldopa | 125 mg once or twice daily | Hyperadrenergic | Hypotension, fatigue, headache, drowsiness, constipation | Rare lupus-like syndrome reported |
| Other drugs | ||||
| Midodrine | 5–15 mg every 4 hours, 3 times daily only | Neuropathic | Hypertension, goose bumps, urinary retention | Not recommended for use within 4-5 hours of sleep |
| Pyridostigmine | 30–60 mg 3 times daily | All | Abdominal cramping, diarrhea, increased sweating | May increase gastrointestinal motility |
| Droxidopa | 100–600 mg 3 times daily | All | Nausea, palpitations, urinary symptoms | May worsen tachycardia |
| Modafinil | 100–200 mg twice daily | “Brain fog” | Headache, dizziness, anxiety, insomnia | May improve cognitive symptoms |