Abstract
A number of both prescription and over the counter drugs, herbal supplements, and miscellaneous substances can increase blood pressure in subjects by degrees that vary substantially within drug classes and individual patients; such increases often remain within the normal range but may cause overt hypertension (BP>140/90) mmHg and even precipitate hypertensive crises. Blood pressure increases are often potentiated by co-existing cardiovascular conditions, age, renal disease, diabetes, obesity, and interactions with other concomitant medications. The need to scrutinize for drugs or other substances that may be contributing to elevated blood pressures or impairing responses to anti-hypertensive medications is critically important, particularly in the evaluation of resistant and refractory hypertension. Anti-hypertensive effects of diuretics, angiotensin converting enzyme inhibitors, angiotensin receptor blockers, and β-blockers may be blunted. The drugs most commonly associated with blood pressure elevations are non-steroidal anti-inflammatory agents, sympathomimetic amines, estrogen-containing oral contraceptives, certain antidepressants, angiogenesis inhibitors, and ephedra. Although most drug-induced blood pressure increases do not, in fact, lead to overt hypertension, systolic and diastolic blood pressure elevations of as little as 2 mmHg lead to significant increases in the risk of cardiovascular events. When a medication with the potential to increase blood pressure is added to a patient’s therapeutic regimen, it is most important to monitor for possible changes in blood pressure even within the normal range. An initial diagnosis of hypertension should not be made until a thorough examination of all over the counter products and herbal substances that a patient may be consuming.