In most cases, the underlying cause for hypertension cannot be identified.

Conditions that may cause hypertension include:

• Cushing's syndrome
• Hemolytic uremic syndrome
• Henoch-Schonlein purpura
• Hyperparathyroidism
• Hyperthyroidism
• Kidney disease
• Periarteritis nodosa
• Pheochromocytoma
• Pregnancy
• Renal artery stenosis
• Wilms tumor

Medications and drugs that may cause hypertension include:

• Alcohol abuse
• Anabolic steroids
• Antidepressants
• Birth control pills
• Cocaine abuse
• Cold medicines and decongestants:
• Pseudoephedrine hydrochloride
• Phenylephrine
• Corticosteroids
• Amphetamines
• Caffeine
• Diet pills