Histamine can be released by mast cells during a wide variety of activities, including exercise. The conditions associated with exercise-induced histamine release include urticaria and asthma. Urticaria, or hives, can develop on the skin. Asthma or bronchoconstriction can lead to shortness of breath.
Histamine
Histamine is a chemical in the human body that is responsible for triggering an inflammatory response. It can be released from basophils and mast cells in the human body. The major actions of histamine in the body include dilating blood vessels, constricting the airways, causing pain and itching after insect bites, stimulating gastric acid secretion and functioning as a neurotransmitter. The symptoms of allergic rhinitis and motion sickness are regulated by histamine.
Exercise Induced Urticaria
Urticaria, or hives, can be the result of histamine release during exercise. The hives can be anywhere from 2 mm to 5 mm, according to the American Family Physician, with the most common locations being the upper chest and neck. These lesions are usually transient and resolve in 20 minutes, but can linger for a few hours. Antihistamines are typically the treatment of choice. Hydroxizine, loratadine and fexofenadine are commonly used to treat hives.
Exercise Induced Asthma
Exercise induced asthma is a condition where exercise or physical activity leads to bronchospasm or constriction of the airway and increased production of mucus, according to Mayoclinic.com. The Asthma and Allergy Foundation of America reports that approximately 80 percent to 90 percent of individuals with allergic asthma will also have exercise-induced asthma. The increase in oxygen demand during exercise can cause bronchospasm through mast cell degranulation and histamine release. Cold air activities such as skiing and ice hockey are more likely to produce symptoms.
Symptoms
The symptoms of exercise induced asthma include coughing, wheezing, chest tightness and shortness of breath, according to the Asthma and Allergy Foundation of America. Onset of symptoms can be during exercise and may actually get worse five to 10 minutes after ceasing the inciting activity. Most patients have resolution in 20 to 30 minutes.
Treatment
Prevention is the best treatment. Warming up properly can help to decrease symptoms. Medications can also be beneficial. The first line medication is a short acting or rescue beta-2 agonist bronchodilator such as albuterol or xopenex used prior to exercise. Longer duration bronchodilators such as salmeterol can prevent symptoms. Medications such as cromolyn and nedocromil can help to stabilize mast cells and prevent histamine release, according to the American Family Physician. Anti-histamines including loratadine, or Claritin; fexofenadine, or Allegra; diphenhydramine. or Benadryl; and hydroxizine, or Atarax.
