ADRA1D and early-onset autosomal dominant Alzheimer disease: ADRA1D (α-1D adrenergic receptor), the target gene with which Guanabenz has been associated, aligns with recent discoveries showing the downregulation of the alpha-D1 adrenergic receptor encoded by ADRA1D in the hippocampus of patients with Alzheimer’s disease and dementia linked to Lewy bodies.