toxic metabolites so that most of the methanol can be excreted harmlessly in the breath and urine without forming its toxic metabolites. This may explain the temporary postponement of symptoms reported in the common remedy of drinking more alcohol to relieve hangover symptoms. Since methanol metabolism is effectively inhibited by consumption of alcohol, methanol accumulates during drinking and only begins to be metabolized once ethanol has been cleared. This delayed action makes it an attractive candidate explanation for delayed post-intoxication symptoms and correlations between methanol concentrations and the presence of hangover symptoms that have been found in studies. Vitamin and electrolyte loss The metabolic processes required for alcohol elimination deplete essential vitamins and electrolytes. Furthermore, alcohol is a diuretic, causing excretion of electrolytes through urination. After a night of drinking, the resulting lack of key B and C vitamins, as well as potassium, magnesium, and zinc may cause fatigue, aching and other hangover-like symptoms. Dehydration Ethanol has a dehydrating effect by causing increased urine production (diuresis), which could cause thirst, dry mouth, dizziness and may lead to an electrolyte imbalance. Studies suggest that electrolyte changes play only a minor role in the genesis of the alcohol hangover and are caused by dehydration effects. Drinking water may help relieve symptoms as a result of dehydration but it is unlikely that rehydration significantly reduces the presence and severity of alcohol hangover. Alcohol's effect on the stomach lining can account for nausea because alcohol stimulates the production of hydrochloric acid in the stomach. Low blood sugar Studies show that alcohol hangover is associated with a decrease in blood glucose concentration (less than 70 ml/dl), but the relationship between blood glucose concentration and hangover severity is unclear. Also known as insulin shock, hypoglycemia can lead to coma or even death. Immune system In current research, the significant relationship between immune factors and hangover severity is the most convincing among all factors so far studied. An imbalance of the immune system, in particular of cytokine metabolism has been identified as playing a role in the pathophysiology of the hangover state. Especially the hangover symptoms nausea, headache, and fatigue have been suggested to be mediated by changes in the immune system. The concentration of several cytokines have been found to be significantly increased in the blood after alcohol consumption. These include interleukin 12 (IL-12), interferon gamma (IFNγ) and interleukin 10 (IL-10). Some pharmacological studies such as