Hypersensitivity is a term that is used to identify situations in which some type of substance or medication triggers an unusually strong and adverse reaction from the immune system. In some instances, hypersensitivity reactions can be extremely uncomfortable, cause permanent damage, or even result in death. There are four commonly accepted types of this condition, with variations of these four supported by different schools of medical thought.
Allergies are normally classified as Type 1 hypersensitivity. These involve allergic reactions that produce an almost immediate effect. The individual may begin to have difficulty breathing, experiencing what amounts to an asthma attack. In more extreme situations, anaphylaxis may occur.
An antibody-dependent or cytotoxic reaction defines define Type 2 situations. Within this category, the hypersensitive reaction manifests with the development of particular conditions such as Goodpasture’s Syndrome, Myasthenia Gravis, or Graves disease. A Type 2 hypersensitivity type has more long range implications.
Type 3 hypersensitivity is classified as an immune complex disease. Within this category, conditions such as Arthus reaction or Serum sickness occur. Along with Type 2, patients diagnosed with Type 3 often require ongoing monitoring in order to keep the triggered condition under control.
DTH, or delayed type hypersensitivity, is known as Type 4. Within this category, patients may develop various dermatological issues that are extremely uncomfortable, experience fluctuation in T-cell levels, and possibly develop conditions such as multiple sclerosis. As with other hypersensitivity types, it is important to identify the substance or medication causing the hypersensitive reaction and prevent any further ingestion of that substance.
One of the best ways to get an idea of how painful hypersensitivity can be is to consider the momentary sharp pain that is often experienced when extremely cold beverages come in contact with a tooth filling. The sudden and intense wave of pain created can often seem unbearable for a brief moment before leveling off. For people with hypersensitive reactions to medicine, food, or some factor in their environment, that level of pain does not subside within a moment, but can last for an extended period of time.
Physicians can often identify what is causing the severe reaction and help the patient learn to avoid the irritant. This may involve changes of prescription medication, avoiding certain spices, herbs or foods, or altering some aspect of the home or work environment. While hypersensitivity can be extremely debilitating and even fatal, it can be managed in most cases.