Triggers for Asthma
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þ Menstrual cycle:
 - "There is a strong association between the peri-menstrual phase of their
   cycle and asthma symptoms. Brenner and Bessman:  Asthma in Plantz and
   Adler's EMedicine, http://www.emedicine.com/emerg/topic43.htm
 - Melatonin (e.g., in dietary supplements) found to worsen nocturnal asthma.
   J Allergy Clin Immunol 2003;112