We name white coat effect (WCE) to the difference between the systolic arterial pressure (SAP)/diastolic AP (DAP) of consulting room and the ambulatory obtained one with ambulatory blood pressure monitoring (ABPM). In our work we analyzed by means of ABPM, the influence of the antihypertensive medicaments on the WCE and the cardiac frequency of use of the antihypertensive ones. Almost experimental study (with a period before and a period later) and descriptive. Primary care. Urban health centre. PARTICIPANTS AND MAIN MEASUREMENTS: Studies of ABPM were realized to 70 hypertense essential patients with good control of the arterial pressure after pharmacological treatment before suspending the antihypertensive medication (phase 1) and to the 4 weeks of leaving the treatment (phase 2). Or all 70 hypertense patients. 18 (26%) did not manage to carry out the second ABPM (unbalanced during the wash) that forced to re-introduce the antihypertensive medicaments. The WCE systolic and diastolic is significantly more raised in patient males in treatment with diuretics with regard to which they use other pharmacological groups. The CF is significantly more raised in patient women who do not take blockaders thread (they use another group) with regard to they take it. In the blockaders alpha the CF is significantly more raised in the women who use it with regard to that they use antihypertensive other one. Of all 52 patients who were realized double ABPM, WCE was significantly top in phase 1 that in 2. In hypertense controlled patients, the diuretics (in males) are the pharmacological group that of more significant way influences on WCE, them raising with regard to the patients who take antihypertensive other one, being in influence the opposite on CF. The women with blockaders thread present values of CF significantly lower than those who use another antihypertensive medication; happening the inverse thing the blockaders alpha. In our consulting room exists a inadequate use of the antihypertensive ones. The WCE is significantly mayor when is submitted to pharmacological treatment.