The post-COVID condition (PCC) is a pathology stemming from COVID-19, and studying its pathophysiology, diagnosis, and treatment is crucial. Neuroinflammation causes the most common manifestations of this disease including headaches, fatigue, insomnia, depression, anxiety, among others. Currently, there are no specific management proposals; however, given that the inflammatory component involves cytokines and free radicals, these conditions must be treated to reduce the current symptoms and provide neuroprotection to reduce the risk of a long-term neurodegenerative disease. It has been shown that cannabis has compounds with immunomodulatory and antioxidant functions in other pathologies. Therefore, exploring this approach could provide a viable therapeutic option for PCC, which is the purpose of this review. This review involved an exhaustive search in specialized databases including PubMed, PubChem, ProQuest, EBSCO, Scopus, Science Direct, Web of Science, and Clinical Trials. Phytocannabinoids, including cannabidiol (CBD), cannabigerol (CBG), and Delta-9-tetrahydrocannabinol (THC), exhibit significant antioxidative and anti-inflammatory properties and have been shown to be an effective treatment for neuroinflammatory conditions. These compounds could be promising adjuvants for PCC alone or in combination with other antioxidants or therapies. PCC presents significant challenges to neurological health, and neuroinflammation and oxidative stress play central roles in its pathogenesis. Antioxidant therapy and cannabinoid-based approaches represent promising areas of research and treatment for mitigating adverse effects, but further studies are needed.

Coronavirus disease 2019 (COVID-19) presents with various symptoms, and some patients develop post-COVID-19 condition (PCC). Vitamin D has shown therapeutic potential in COVID-19 and may offer benefits for PCC. The aim of this study was to evaluate the differences associated with two supplementation strategies (bolus and daily) on interleukin-6 (IL-6) levels, glutathione peroxidase (GPx) activity, and clinical outcomes in PCC patients, regardless of whether target 25 (OH) D levels reached the ideal range. We conducted a self-controlled study in which 54 participants with PCC were supplemented with vitamin D₃ (n = 28 bolus and n = 26 daily) for 2 months. Blood samples were collected to measure IL-6 levels and GPx activity using spectrophotometric methods. The Hospital Anxiety and Depression Scale (HADS) was used to assess mental function. Both bolus and daily vitamin D supplementation were significantly associated with increased GPx activity and decreased IL-6 levels. Daily supplementation was additionally associated with a significant reduction in anxiety and depression scores. However, neither regimen was associated with improvements in cough, dyspnea, or fatigue. These findings suggest a potential association between vitamin D supplementation and improvements in antioxidant and neuropsychiatric parameters in PCC, possibly mediated by its immunomodulatory and antioxidant properties. Further placebo-controlled trials are warranted to determine whether these observed associations reflect causal relationships.