This critical review of the literature shows that there is a close link between the microbiome, the gut, and the brain in Parkinson’s disease. The vagus nerve, the main component of the parasympathetic nervous system, is involved in the regulation of immune response, digestion, heart rate, and control of mood. It can detect microbiota metabolites through its afferents, transferring this gut information to the central nervous system. Preclinical and clinical studies have shown the important role played by the gut microbiome and gut-related factors in disease development and progression, as well as treatment responses. These findings suggest that the gut microbiome may be a valuable target for new therapeutic strategies for Parkinson’s disease. More studies are needed to better understand the underlying biology and how this axis can be modulated for the patient’s benefit.

Reversible Cerebral Vasoconstriction Syndrome (RCVS) is a neurovascular condition characterized by a severe sudden-onset headache that may be associated with focal neurological deficits. On imaging, the suggestive finding corresponds to multifocal vasoconstriction of the cerebral arteries, with a spontaneous resolution of approximately 12 weeks. The identification of precipitating factors and diagnosis must be carried out early, so that adequate management is established and the patient has a good prognosis, given the risk of secondary complications and residual neurological deficits. This study consists of a literature review based on the analysis of articles published between 2017 and 2022 in PubMed, SciELO, and ScienceDirect on RCVS, intending to understand the clinical and radiological characteristics, diagnosis, treatment, and prognosis of patients with RCVS. The pathophysiology, drug management, and prognosis still lack solid evidence; therefore, further studies on RCVS are needed to expand medical knowledge and avoid underdiagnosis and inadequate treatment of this important condition.