Antihypertensive agents are one of the most commonly prescribed classes of medications in the country, but patient adherence rates are low. To better understand why rates are low, the authors used data from the 2005 HealthStyles survey and found that among the 1432 respondents who received prescriptions for antihypertensive medications, 407 (28.4%) reported having difficulty taking their medication. ``Not remembering'' was the most common reason reported (32.4%), followed by cost (22.6%), having no insurance (22.4%), side effects (12.5%), other reasons (12.3%), not thinking there is any need (9.3%), and having no health care provider (4.7%). In a multivariate model, younger age, lower income, having mental function impairment, and having had a blood pressure check more than 6 months earlier were factors significantly associated with reporting difficulty taking prescribed antihypertensive drugs. Control of hypertension is a significant public health issue, and alleviating barriers to medication adherence should be a major goal toward hypertension management.