Caucasian men, and Blacks of both sexes have a higher incidence of significant hypertension .
Essential hypertension has no identifiable cause.
Secondary hypertension is hypertension that occurs because of another disorder. Drug-induced hypertension is a form of secondary hypertension caused by a response to medication. Drug-induced hypertension can also be a result of stopping the use of antihypertensive medications such as clonidine. This is called rebound hypertension. If you are unsure of the likely effects, consult the health care provider or pharmacist before using the substance or medication.