About 3,000,000 people in the United States have hay fever. Most cases are due to sensitivity to ragweed pollen. These pollens may be blown as much as fifty miles from their sources. Every area has its own pollens, and charts have been prepared showing the prevailing pollens in each portion of each state.
The allergists say that some time is required to sensitize the individual with hay fever. The antibodies get in the mucous membranes of the nose, in the skin, and in the bronchial tubes so that some asthma may accompany hay fever, and the skin tests are positive for the offending allergens.
For the hay fever patient the first step is to find the pollens to which he is sensitive. This may be done by a series of skin tests. He then has the choice of moving out of the area to a place where he will be free from such contact, or of being desensitized with injections of the offending substance. Usually treatment is begun a few months before the hay fever season begins. Gradually the strength and amount of the injections are increased, so that the patient is receiving large doses by the time the season begins. In some instances treatments are given every two or three weeks all through the year. The use of such methods requires skill and experience, because patients sometimes react most seriously to injections of large doses of the substances to which they are sensitive.
Among other measures used for hay fever is the use of air conditioning, air filters, masks and covering of windows to exclude pollen. Most physicians now supplement the specific treatment with use of the antihistaminic drugs, which are often remarkably effective in stopping the most annoying symptoms.
Vasomotor rhinitis is a condition like hay fever due to sensitivity to dusts or food substances.