Objectives: Antidepressant use is often reported as a risk factor for Orthostatic Hypotension (OH), however this relationship has never been explored in those with mild/moderate Alzheimer Disease (AD), who may represent a particularly vulnerable cohort. Methods: We performed a cross‐sectional analysis of baseline data from the NILVAD study. Participants with mild‐moderate AD were recruited from 23 centres in nine countries. Systolic and Diastolic Blood Pressure (SBP/DBP) was recorded in the seated position and after both 1 and 5 minutes of standing. OH was defined as a drop of ≥20 mmHg SBP/≥10 mmHg DBP. We examined the relationship between antidepressant use, orthostatic BP drop and the presence of OH, controlling for important covariates. Results: Of 509 participants (72.9 ± 8.3 years, 61.9% female), two‐fifths (39.1%; 199/509) were prescribed a regular antidepressant. Antidepressant use was associated with a significantly greater SBP and DBP drop at 5 minutes (β: 1.83, 0.16‐3.50, P = .03 for SBP; β: 1.13, 0.02‐2.25, P