When the diagnosis is made, the doctor starts treatment by injecting a small amount of the extract under the patient’s skin. At each visit, the dose is increased. It takes usually between fifteen and twenty injections to bring the person to complete immunity no matter how sensitive he is. The most often that injections can be given, unless the patient is being underdosed, is about twice weekly. Since immunization should be complete before the sea-son starts, at least ten weeks should be allowed. This is the scheme of preseasonal treatment, the one in most common use today. Efforts have been made to reduce the number of injections by making extracts that are absorbed more slowly by the body and giving a larger dose each time. There is reason for expecting that one or more of the methods proposed will be found to be practical, but at present they must still be considered as being experimental. Perhaps some day we will reach the ideal of one injection for complete immunization.
Once the patient is immunized, treatment may be stopped and he will usually retain enough immunity to carry him through the season. Many allergists prefer, how-ever, to continue treatment by giving an injection every week or two throughout the season. And many also like to maintain the immunity all year round instead of stop-ping each winter and then starting all over in the spring. This is the perennial method and there is good evidence for believing that it is the most effective method there is.
While various doctors use different systems, a typical plan is to start with preseasonal treatment, then give an injection every two weeks during the season, and finally an injection every four weeks until about a month before the next season starts. Four or five injections are then given at weekly intervals with fresh extract, these being required to make up the loss of immunity suffered through deterioration of the extract. About the same number of injections is required per year in both preseasonal and perennial methods.
Many physicians believe that after symptoms have started it is too late to do anything with specific treatment. This is far from the truth. Coseasonal treatment is entirely practical and is actually the method of choice of some allergists. The experience of most doctors is that better results are usually obtained by preseasonal treat-ment, but sometimes almost complete relief is given with coseasonal treatment and usually a distinct lessening of symptoms may be accomplished. Two methods of inoculation are in use, the subcutaneous and the intracutaneous. Whichever is chosen, injections are given daily, either under or into the skin, the dose being increased each day until symptoms cease. The patient is then told not to return until the symptoms come back. Each time he re-turns, the same dose as the one which first cleared up the symptoms is given him. This is kept up until the season is over.
Specific therapy, whether coseasonal, preseasonal, or perennial, is good and in the writer’s opinion should be given to every hay fever patient who is unable to practice complete avoidance. But it is not one hundred percent perfect nor is it foolproof. No matter how careful the doctor is, there will be times when a larger dose is given than the patient can stand, and a constitutional or systemic reaction will occur. Such a mishap is not to be construed as being due to the doctor’s negligence or ignorance. The first time a person is being treated, the dosage increase is largely a matter of guesswork based on past experience and knowledge of what people can usually stand. Some patients are more prone to constitutional re-actions than others and it is not possible always to keep the dosage below the individual’s tolerance. Fortunately, if proper precautions are taken, these reactions are more disconcerting and unpleasant than serious. If a reaction comes on within five minutes of the injection, it is likely to be fairly violent. If it occurs over half an hour after the injection, it will probably be fairly mild, though the physician should always be called. Patients should wait in the doctor’s office for at least half an hour after every injection so that they can obtain immediate treatment if a reaction occurs, and the degree of swelling at the site of injection should be examined by the doctor before the patient is allowed to leave.
These constitutional reactions manifest themselves in different ways. Usually the first indication of something wrong is an itching or tingling of the scalp, face, or palms of the hands. It is then that the doctor should be informed of what is happening. If the condition progresses, the patient may burst forth into hives, he may get hay fever, or he may come down with asthma. These are usually controlled quite readily by an injection of epinephrine (adrenalin).
All patients undergoing immunization therapy for an allergic condition should carry a capsule of ephedrine with them. Then if they feel the symptoms of a constitutional reaction coming on after leaving the doctor’s office, they can take the capsule, which in itself may be enough to control the attack; but they should not get a false sense of security from this and should call the doctor anyhow. It is also well to remember that a tourniquet around the arm above the site of injection will stop the absorption of the extract by the body and will tend to lessen the severity of the attack. But don’t forget to loosen the tourniquet for a minute or two at least every twenty minutes while waiting for the doctor.
Recently there has been a wave of enthusiasm for taking pollen orally instead of by injection. This method was discarded as ineffective years ago and it is hard to see why it is being pushed again now. New work on this subject shows the results to be far below those usually obtained by the injection methods and complications such as gastrointestinal upsets are fairly common. An occasional person may get good results from this method, but it hardly seems worth trying.
IMMUNITY VS. DESENSITIZATION
In this discussion the words “desensitization” and “de-sensitize” have been intentionally avoided. But because they are so commonly used in allergic literature, some mention must be made of them. They are used in place of the “immunization” and “immunize” that are used here. When a person is treated for hay fever successfully, if skin tests are done he will be found to give positive reactions the same as he did before treatment. He is still sensitive and he cannot therefore have been desensitized.
However, he is not having symptoms, so something has happened. It is known that what has happened is that he has elaborated what are called immunizing or blocking antibodies which protect him from the symptoms. He has therefore been immunized. The word desensitize to de-scribe allergic immunization is a misnomer which is rap-idly passing out of the literature. But as long as it remains, we must know what it means.