title: Tobacco, Nicotine, and Headache.
abstract: BACKGROUND
  Migraineurs variably attribute the cause of their headache to tobacco exposure, whereas tobacco is often stated to cause headache-related disability worldwide. Given tobacco's physiological and emotional addictiveness and migraine's substantial economic impact, improved functionality can be difficult for those with migraine exposed to tobacco products. Environmental tobacco exposure in indoor spaces and workplaces is associated with exacerbation of headache. Avoidance of headache triggers is included in most comprehensive migraine treatment programs, yet tobacco awareness, avoidance, or coping is rarely emphasized as part of that regimen.
  
  
  OBJECTIVE
  The aims of this study were to examine the various types of tobacco products to which headache sufferers are exposed and the known basic mechanisms by which tobacco (nicotine) exposure promotes headache pain, and to review the extensive literature on tobacco related to headache with a detailed descriptive narrative providing the basis for conclusions regarding association of noncluster headache-related tobacco exposure. Tobacco-related recommendations are offered.
  
  
  METHODS
  MEDLINE, EMBASE, and Google Scholar databases were searched without yearly restriction through the date of submission (May 2015), using the MeSH terms "tobacco," "tobacco products," "smoking," "tobacco use," "headache," and "headache disorders." The selection of articles was not limited to English studies or to humans. Articles were excluded when "headache" and "tobacco" were not both mentioned with data provided. Case series were included. Bibliographies of all articles were screened for additional relevant articles.
  
  
  RESULTS
  Although migraineurs worldwide report tobacco smoke among triggers, it is rarely among the highest in frequency, and biases abound with predominantly noncontrolled retrospective data. Prospective population-based diary data are extremely limited, and no controlled trials exist to confirm a cause and effect for headache of any type. Although some studies are nonsupportive and even conflicting, headache, pain, and tobacco exposure currently remain associated.
  
  
  CONCLUSIONS
  Conflicting data support the validity of patient-reported environmental tobacco exposure as a headache trigger. Prospective controlled studies are needed, but unlikely to be performed, to determine the extent that tobacco influences the headache process, in addition to other under-recognized factors. Meanwhile, because of numerous other negative health effects, decreased tobacco exposure should be recommended to headache patients of all ages in hopes of decreasing disability and improving functionality.
authors.affiliation: Department of Neurology, University of Minnesota School of Medicine, Minneapolis, MN, USA.
authors.forename: Frederick R
authors.initials: FR
authors.lastname: Taylor
mesh_terms: D000382:Agricultural Workers' Diseases / Q000139:chemically induced; D015982:Bias; D003027:Cluster Headache / Q000139:chemically induced; D066300:Electronic Nicotine Delivery Systems / Q000009:adverse effects; D004781:Environmental Exposure / Q000009:adverse effects*; D006801:Humans; D008881:Migraine Disorders / Q000139:chemically induced* / Q000453:epidemiology / Q000503:physiopathology; D009538:Nicotine / Q000009:adverse effects* / Q000494:pharmacology; D011446:Prospective Studies; D012189:Retrospective Studies; D012307:Risk Factors; D012907:Smoking / Q000009:adverse effects*; D062789:Tobacco Products / Q000009:adverse effects*; D014028:Tobacco Smoke Pollution / Q000009:adverse effects*
chemical_list: D014028:Tobacco Smoke Pollution; D009538:Nicotine
keywords: headache; migraine; nicotine; smoke; smokeless; tobacco