Autism spectrum disorder (ASD) and epilepsy are complex, frequently co-occurring neurodevelopmental and neurological disorders that share key mechanisms, such as altered neurotransmission, oxidative stress, neuroinflammation, and gut-brain axis disruption. Despite pharmacological advances, current treatments often provide only partial relief and are associated with significant side effects. The comorbidity of ASD and epilepsy, affecting millions worldwide, remains under-recognised and poorly addressed, imposing a profound burden on patients, families, and healthcare systems through reduced quality of life, increased caregiving demands, and substantial social and economic costs. This review highlights the convergent pathways shared between ASD and epilepsy, including immune dysregulation, synaptic dysfunction, and metabolic imbalance, which create opportunities for unified therapeutic strategies. Marine algae have emerged as a sustainable source of bioactive compounds offering a unique potential to address these overlapping pathologies. Algal polyunsaturated fatty acids, carotenoids, polyphenols, polysaccharides, and vitamins have antioxidant, anti-inflammatory, neuroprotective, and microbiota-modulating activities. By addressing both the biological underpinnings and clinical burden of ASD-epilepsy comorbidity, algae-based strategies represent a novel and ecologically sustainable direction for mitigating ASD-epilepsy comorbidity and advancing marine-inspired neurotherapeutics.
