Valerian (Valeriana officinalis L.), passionflower (Passiflora incarnata L.), and ginkgo (Ginkgo biloba L.) are among the most widely used medicinal plants in European phytotherapy, with well-documented traditional use for anxiety, insomnia, cognitive decline, attention-deficit/hyperactivity disorder (ADHD), and Parkinson’s disease. This narrative review critically analyses available clinical, pharmacological, toxicological, and regulatory data on these three species in the context of central nervous system (CNS) disorders. A comprehensive literature search was conducted in PubMed, Scopus, and the Cochrane Library; regulatory documents from the European Medicines Agency (EMA), the European Scientific Cooperative on Phytotherapy (ESCOP), and the World Health Organization (WHO) were also included. Valerian showed the most consistent clinical evidence for an improvement in sleep quality and reduction in anxiety. Passionflower demonstrated anxiolytic and mild sedative effects in several controlled trials. Ginkgo showed clinically relevant benefits in mild cognitive impairment, dementia, and vertigo. All three plants exhibited acceptable safety profiles at the recommended doses; however, significant drug interactions were identified, notably ginkgo’s inhibition of CYP2C19 and antiplatelet effects, and valerian’s potentiation of CNS depressants. Regulatory frameworks across EU member states remain inconsistent. Further high-quality randomized controlled trials with standardized extract characterization are needed.