Ethanol and congeners (e.g., histamine, serotonin) in alcoholic beverages are capable of activating transient receptor potential cation channel subfamily V member 1 and Toll-like receptor 4, thereby promoting the release of pro-inflammatory cytokines and triggering neuroinflammatory responses in the trigeminal vascular system.[20] However, variations in congener composition across different alcoholic beverages – e.g., pro-inflammatory aldehydes in spirits versus anti-inflammatory flavonoids in red wine – may give rise to heterogeneous effects on headache risk. The gene discussed is TLR4; the disease is Headache.