Arterial hypertension is among the leading risks for mortality. This burden requires in hypertensive patients the use of single, double or more antihypertensive drugs. The relationship between intracranial pressure (ICP) and arterial blood pressure is complex and still under debate. The impact of antihypertensive drugs on ICP is unknown. We wanted to understand whether the use of antihypertensive drugs has a significant influence on ICP and cerebrospinal fluid (CSF)/brain related parameters.In a cohort of 95 patients with suspected normal pressure hydrocephalus, we prospectively collected drug details according to the Anatomical Therapeutic Chemical (ATC) classification. Lumbar infusion studies were performed. Using ICM+ software, we calculated at baseline and plateau ICP and pulse amplitude, resistance to CSF outflow, elastance, and pressure in the sagittal sinus and CSF production rate. We studied the influence of the administration of 1, 2, 3 or more antihypertensive drugs on ICP-derived parameters. We compared the data using Student's and Mann-Whitney tests or Chi-squared and Fisher's exact test.Elastance is significantly higher in patients with at least one antihypertensive drug compared with patients without medication. On the contrary, pressure volume index (PVI) is significantly decreased in patients with antihypertensive drugs compared with patients not on these medications. However, the number of antihypertensive drugs does not seem to influence other ICP parameters.Patients on antihypertensive drugs seem to have a stiffer brain than those not on them.