Epidemiology
Etiology
Pathophysiology
Clinical features
- Classic Triad (episodic, paroxysmal):
- Pounding headache.
- Diaphoresis (profuse).
- Tachycardia/Palpitations.
- Refractory/Resistant HTN: Paroxysmal (50%) or persistent.
- Other features: Anxiety, panic-like attacks, orthostatic hypotension (due to low plasma volume), hyperglycemia (impairs insulin secretion/increases glycogenolysis). c
- Triggers: Surgery/anesthesia induction, exercise, defecation, trauma, foods high in tyramine (cheese, red wine). c
Diagnostics
Differential diagnostics
| Condition | Key Differentiating Features | Confirmatory Test |
|---|
| Anxiety/Panic | Psychological triggers; lacks severe paroxysmal HTN; may respond to psychiatric meds. | Normal metanephrines. |
| Hyperthyroidism | Persistent symptoms (not spells); goiter, proptosis; fine tremor. | Low TSH, High T4/T3. |
| Carcinoid Syndrome | Classic triad: Flushing, Diarrhea, Wheezing; right-sided heart valve disease. | High urinary 5-HIAA. |
| Illicit Drug Use | History of use; positive urine toxicology screen. | Positive tox screen; metanephrines normalize with abstinence. |
| Clonidine Withdrawal | History of abrupt clonidine cessation; symptoms resolve with clonidine re-administration. | Clonidine suppression test. |
| Essential HTN | Often asymptomatic; lacks paroxysmal spells; responds to standard antihypertensives. | Normal metanephrines. |
Treatment