Table 1. Causes of resistant hypertension.

1. Substances ingested by the patient (salt, licorice, decongestants, nonsteroidal anti-inflammatory agents other than sulindac) (25)

2. Non-compliance (about half of patients will admit it if asked in a non-judgemental manner) (26)

3. Therapeutic inertia (failure to initiate or intensify medical therapy)

4. Secondary hypertension (pheochromocytoma, primary aldosteronism, renovascular hypertension, etc.)

5. Diagnostic inertia (failure to investigate the underlying cause of the hypertension) (27,28)