Before any allergy problem is solved, or any theory of allergy is tested, certain fundamental criteria must be satisfied. A patient who receives a drug may not be aware of the planning and thought that went into the research leading to approval of the drag or drags the patient uses and depends on every day. The question to be answered in the research must first be identi­fied clearly. Then time and effort must be devoted to organizing the research. For example, how many subjects should be used? How many comparison groups? How many observations, and what type, should be made? What should be the duration of observations for the observations to be meaningful? For comparisons to be statistically significant, the volunteers must be allocated without bias to treat­ment groups. Researchers are constantly concerned about how data is collected so that results will be unbiased and valid. It is no wonder that researchers become upset when unsubstanti­ated, sensational statements are made claiming, for instance, break­throughs in research. Unless hypotheses and breakthroughs in therapy are confirmed by scientific tests and properly designed experimenta­tion, they do not deserve public acceptance and confidence. In reviewing research in the field of allergy, both current and future, researchers often start with population studies that have been used to gain information about the characteristics of an allergic disease and the frequency with which it occurs.

Hypersensitivity is a condition in which the immune system reacts to antigens that cause tissue damage and disease. This is in contrast to the normal beneficial effect of the immune response. Hypersensitivity reactions are usually divided into the following four main types: Anaphylactic This type is mediated by allergic (IgE) antibodies. Hay fever, certain types of asthma, hives, some food and drug reac­tions, and systemic anaphylaxis are examples. See also Anaphylaxis. Cytotoxic In this type of reaction, antibodies of the IgG and IgM classes react with antigens present in cell membranes. The antigen-antibody reaction activates the complement system, culminating in lysis (destruction) of the cell. An example of this type of reaction is the destruction of red blood cells that occurs as a result of an auto­immune reaction. Immune-complex mediated This type of reaction results from deposits of antigen-antibody complexes in different tissues. The com­plement system is also involved. Examples of this type of reaction are serum sickness, some types of drug reactions, and certain renal diseases. Delayed, or cell-mediated hypersensitivity Delayed hypersensi­tivity is a form of immune response characterized by a process of inflammation that reaches its maximum intensity twenty-four to forty-eight hours after exposure to the offending substance, or antigen. Common examples are the skin lesions associated with contact to poison ivy and metals and the reaction to numerous fungi, viruses, and transplanted organs. It is mediated by sensitized lymphocytes. See also Allergy.

The type of reaction you describe —the "swelling" is of the uvula, flesh that hangs in the back of the throat—may well be caused by an allergy. The inhalants you mention, however, are less likely causes of the problem than are foods or medications. To determine the causes precisely, you should seek the advice of an allergist. Then appropriate remedies can be prescribed.

Combine ingredients and simmer for 15 minutes.

Hereditary angiodema is a rare, inherited disorder due to a deficiency of a normally occurring blood protein that inhibits the complement system. The disease produces recurrent abdominal pain and episodes of swelling, mostly in the face and extremities or in the air passages. It can be fatal if swelling, which occurs in the tongue, throat, or larynx, shuts off air to the lungs.

In addition to theophylline discussed above, metaproterenol and terbutaline (Bricanyl and Brethine) are described as "more specific" in the marketing literature; that is, they cause bronchial smooth muscle dilation, or relaxation, without having an appreciable effect on the heart. Ephedrine, a component of such combination products as Tedral, can be useful in treating some individuals when it is given around the clock in conjunction with theophylline drugs. All the above-mentioned oral agents should be used with caution in patients suffering from high blood pressure, heart disease, hyperthyroidism, or respiratory failure.

Emphysema is a chronic disease of the lungs, in which the alveoli are permanently damaged or destroyed. It is typically characterized by difficult breathing and is associated with heavy, prolonged cigarette smoking.

Allergens are a special type of antigen that are responsible for clinical symptoms in allergic people. Antigens are foreign sub­stances that induce an immune response in normal individuals. A person may be exposed to an allergen by inhalation, ingestion, or penetration of the skin. Allergens that are inhaled can be of either indoor or outdoor varieties, although the two environments appear to be intimately related. The allergenic particles in outdoor allergens are derived mainly from components of plants that are widely dispersed by wind. Ex­amples of these particles are plant pollen, spores from fungi, actinomy-cetes, bacteria, mosses, and ferns. Their composition varies by region, which, in turn, is influenced by, among other things, climate, cycles of plant growth, wind, temperature variations, rain, and agricultural activities. The major outdoor allergens consist of plant pollen and fungal spores. Descriptions of these allergens may be found under separate headings. Indoor allergens occur primarily in the home and the workplace. The most important allergens in this category are house dust, mites, animal danders, feathers, mold spores, and pollen. The indoor en­vironment is affected by air-conditioning and heating systems, by humidifiers, people’s personal habits, and their hobbies. The work environment is affected by such factors as smoking, the type of job or industry, degree of ventilation and humidification. A person’s oc­cupation may be the only source of exposure to the allergens respon­sible for his or her symptoms. It is becoming increasingly important to study occupations as a potential source of allergens. Respiratory symptoms associated with an occupation may be caused by an allergy or by an irritant effect on the respiratory tract. Some industrial materials are also known to cause asthma on an allergic basis. Among these are:

See Insect Allergy.