Neurotransmitters are intermediate chemicals that allow neurons within the brain to communicate with one another. The amino acid glutamate is the most abundant excitatory neurotransmitter, and it is involved in the majority of neuronal transmission. Excitotoxicity refers to the molecular pathology that arises as a result of the buildup of glutamate, which has specific intracellular and extracellular concentrations in the space between cells. The fundamental cause of several neurological diseases as well as certain brain disorders, such as glioblastoma, is known as excitotoxicity. Homeostatic processes are wrongly processed as a result of excitotoxicity, as are catalytic enzyme activation, an increase in harmful potential radicals in the environment, and disruptions in cell energy production. This abnormal state produces neuronal malfunction, neurodegenerative disorders, and diseases such as glioblastoma. Glioblastoma multiforme (GBM) is the most common primary brain tumor and is an aggressive type of cancer derived from glial cells. Excitotoxicity is caused by excessive glutamate release from glioma cells. Increased glutamate concentration in the tumor area activates glioma cells expressing glutamate receptors via the signal transduction pathway. Increased glutamate levels in the tumor and surrounding tissues are hypothesized to be responsible for necrosis in malignant gliomas, excitotoxic death of surrounding normal neurons, glioma-related convulsions, and proliferation.