Drug allergy

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Drug allergy
Specialty Immunology, pharmacology

A drug allergy is an allergy to a drug, most commonly a medication, and is a form of adverse drug reaction. Medical attention should be sought immediately if an allergic reaction is suspected.

Contents

An allergic reaction will not occur on the first exposure to a substance. The first exposure allows the body to create antibodies and memory lymphocyte cells for the antigen. However, drugs often contain many different substances, including dyes, which could cause allergic reactions. This can cause an allergic reaction on the first administration of a drug. For example, a person who developed an allergy to a red dye will be allergic to any new drug which contains that red dye.

A drug allergy is different from an intolerance. A drug intolerance, which is often a milder, non-immune-mediated reaction, does not depend on prior exposure.

Signs and symptoms

Symptoms of drug hypersensitivity reactions can be similar to non-allergic adverse effects. Common symptoms include: [1]

Causes

Some classes of medications have a higher rate of drug reactions than others. These include antiepileptics, antibiotics, antiretrovirals, NSAIDs, and general and local anesthetics. [2]

Risk factors

Risk factors for drug allergies can be attributed to the drug itself or the characteristics of the patient. Drug-specific risk factors include the dose, route of administration, duration of treatment, repetitive exposure to the drug, and concurrent illnesses. Host risk factors include age, sex, atopy, specific genetic polymorphisms, and inherent predisposition to react to multiple unrelated drugs (multiple drug allergy syndrome). [3] A drug allergy is more likely to develop with large doses and extended exposure.[ citation needed ]

People with immunological diseases, such as HIV and cystic fibrosis, [2] or infection with EBV, CMV, or HHV6, [4] are more susceptible to drug hypersensitivity reactions. [2] These conditions lower the threshold for T-cell stimulation. [4]

Mechanisms

There are two broad mechanisms for a drug allergy to occur: IgE or non-IgE mediated. In IgE-mediated reactions, also known as immunoglobulin E mediated reactions, drug allergens bind to IgE antibodies, which are attached to mast cells and basophils, resulting in IgE cross-linking, cell activation and release of preformed and newly formed mediators. [5]

Most drugs do not cause reactions in themselves, but by the formation of haptens. [2]

Types

Drug allergies or hypersensitivities can be broadly divided into two types: immediate reactions and delayed reactions. Immediate reactions take place within an hour of administration and are IgE mediated, while delayed reactions take place hours to weeks after administration and are T-cell mediated. The first category is mostly mediated through specific IgE, whereas the latter is specifically T-cell mediated. [2]

Management

Management of drug allergy consists principally of avoidance or discontinuation of the causative drug. [6] Treatment is largely supportive and symptomatic. [6] It may consist of topical corticosteroids and oral antihistamines for cutaneous symptoms such as hives and itching. [6] Mild cutaneous reactions can be managed with antihistamines only. [6] However, antihistamines cannot antagonize activated histamine that has already been released from mast cells. [7] In severe cases of drug allergy, systemic corticosteroids may be used. [6] Corticosteroids are limited by a delayed onset of action of greater than 45 minutes as they act via gene modulation. [7] If anaphylaxis occurs, injectable epinephrine is to be used. [6] [8] If a person is allergic to a drug and no suitable alternative exists, a desensitization procedure with the drug, in which the drug is introduced slowly at very low doses such that tolerance to the drug allergy develops, can be employed. [6]

See also

Related Research Articles

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Allergies, also known as allergic diseases, are a number of conditions caused by hypersensitivity of the immune system to typically harmless substances in the environment. These diseases include hay fever, food allergies, atopic dermatitis, allergic asthma, and anaphylaxis. Symptoms may include red eyes, an itchy rash, sneezing, coughing, a runny nose, shortness of breath, or swelling. Food intolerances and food poisoning are separate conditions.

An allergen is a type of antigen that produces an abnormally vigorous immune response in which the immune system fights off a perceived threat that would otherwise be harmless to the body. Such reactions are called allergies.

<span class="mw-page-title-main">Anaphylaxis</span> Life-threatening allergic reaction

Anaphylaxis is a serious, potentially fatal allergic reaction and medical emergency that is rapid in onset and requires immediate medical attention regardless of use of emergency medication on site. It typically causes more than one of the following: an itchy rash, throat closing due to swelling which can obstruct or stop breathing; severe tongue swelling which can also interfere with or stop breathing; shortness of breath, vomiting, lightheadedness, loss of consciousness, low blood pressure, and medical shock. These symptoms typically start in minutes to hours and then increase very rapidly to life-threatening levels. Urgent medical treatment is required to prevent serious harm or death, even if the patient has used an epipen or has taken other medications in response, and even if symptoms appear to be improving.

<span class="mw-page-title-main">Hypersensitivity</span> Medical condition

Hypersensitivity refers to undesirable reactions produced by the normal immune system, including allergies and autoimmunity. They are usually referred to as an over-reaction of the immune system and these reactions may be damaging and uncomfortable. This is an immunologic term and is not to be confused with the psychiatric term of being hypersensitive which implies to an individual who may be overly sensitive to physical and/or emotional stimuli. Although there is a relation between the two – studies have shown that those individuals that have ADHD are more likely to have hypersensitivity reactions such as allergies, asthma, eczema than those who do not have ADHD. Hypersensitivity reactions can be classified into four types.

<span class="mw-page-title-main">Food allergy</span> Hypersensitivity reaction to a food

A food allergy is an abnormal immune response to food. The symptoms of the allergic reaction may range from mild to severe. They may include itchiness, swelling of the tongue, vomiting, diarrhea, hives, trouble breathing, or low blood pressure. This typically occurs within minutes to several hours of exposure. When the symptoms are severe, it is known as anaphylaxis. A food intolerance and food poisoning are separate conditions, not due to an immune response.

<span class="mw-page-title-main">Hives</span> Skin disease characterized by red, raised, and itchy bumps

Hives, also known as urticaria, is a kind of skin rash with red, raised, itchy bumps. Hives may burn or sting. The patches of rash may appear on different body parts, with variable duration from minutes to days, and does not leave any long-lasting skin change. Fewer than 5% of cases last for more than six weeks. The condition frequently recurs.

<span class="mw-page-title-main">Type I hypersensitivity</span> Medical condition

Type I hypersensitivity is an allergic reaction provoked by re-exposure to a specific type of antigen referred to as an allergen. Type I is distinct from type II, type III and type IV hypersensitivities.

<span class="mw-page-title-main">Allergic conjunctivitis</span> Medical condition

Allergic conjunctivitis (AC) is inflammation of the conjunctiva due to allergy. Although allergens differ among patients, the most common cause is hay fever. Symptoms consist of redness, edema (swelling) of the conjunctiva, itching, and increased lacrimation. If this is combined with rhinitis, the condition is termed allergic rhinoconjunctivitis (ARC).

<span class="mw-page-title-main">Peanut allergy</span> Type of food allergy caused by peanuts

Peanut allergy is a type of food allergy to peanuts. It is different from tree nut allergies, because peanuts are legumes and not true nuts. Physical symptoms of allergic reaction can include itchiness, hives, swelling, eczema, sneezing, asthma attack, abdominal pain, drop in blood pressure, diarrhea, and cardiac arrest. Anaphylaxis may occur. Those with a history of asthma are more likely to be severely affected.

<span class="mw-page-title-main">Soy allergy</span> Type of food allergy caused by soy

Soy allergy is a type of food allergy. It is a hypersensitivity to ingesting compounds in soy, causing an overreaction of the immune system, typically with physical symptoms, such as gastrointestinal discomfort, respiratory distress, or a skin reaction. Soy is among the eight most common foods inducing allergic reactions in children and adults. It has a prevalence of about 0.3% in the general population.

<span class="mw-page-title-main">Milk allergy</span> Type of food allergy caused by milk

Milk allergy is an adverse immune reaction to one or more proteins in cow's milk. Among the possible symptoms is anaphylaxis, a potentially life-threatening condition that requires treatment with epinephrine, among other measures. However, symptoms may take hours to days to manifest, with symptoms including atopic dermatitis, inflammation of the esophagus, enteropathy involving the small intestine and proctocolitis involving the rectum and colon.

<span class="mw-page-title-main">Egg allergy</span> Type of food allergy caused by eggs

Egg allergy is an immune hypersensitivity to proteins found in chicken eggs, and possibly goose, duck, or turkey eggs. Symptoms can be either rapid or gradual in onset. The latter can take hours to days to appear. The former may include anaphylaxis, a potentially life-threatening condition which requires treatment with epinephrine. Other presentations may include atopic dermatitis or inflammation of the esophagus.

<span class="mw-page-title-main">Tree nut allergy</span> Medical condition

A tree nut allergy is a hypersensitivity to dietary substances from tree nuts and edible tree seeds causing an overreaction of the immune system which may lead to severe physical symptoms. Tree nuts include, but are not limited to, almonds, Brazil nuts, cashews, chestnuts, filberts/hazelnuts, macadamia nuts, pecans, pistachios, shea nuts and walnuts.

<span class="mw-page-title-main">Wheat allergy</span> Medical condition

Wheat allergy is an allergy to wheat which typically presents itself as a food allergy, but can also be a contact allergy resulting from occupational exposure. Like all allergies, wheat allergy involves immunoglobulin E and mast cell response. Typically the allergy is limited to the seed storage proteins of wheat. Some reactions are restricted to wheat proteins, while others can react across many varieties of seeds and other plant tissues. Wheat allergy is rare. Prevalence in adults was found to be 0.21% in a 2012 study in Japan.

In medicine, desensitization is a method to reduce or eliminate an organism's negative reaction to a substance or stimulus.

<span class="mw-page-title-main">Allergic response</span>

An allergic response is a hypersensitive immune reaction to a substance that normally is harmless or would not cause an immune response in everyone. An allergic response may cause harmful symptoms such as itching or inflammation or tissue injury.

Kounis syndrome is defined as acute coronary syndrome caused by an allergic reaction or a strong immune reaction to a drug or other substance. It is a rare syndrome with authentic cases reported in 130 males and 45 females, as reviewed in 2017; however, the disorder is suspected of being commonly overlooked and therefore much more prevalent. Mast cell activation and release of inflammatory cytokines as well as other inflammatory agents from the reaction leads to spasm of the arteries leading to the heart muscle or a plaque breaking free and blocking one or more of those arteries.

<span class="mw-page-title-main">Fish allergy</span> Type of food allergy caused by fish

Fish allergy is an immune hypersensitivity to proteins found in fish. Symptoms can be either rapid or gradual in onset. The latter can take hours to days to appear. The former may include anaphylaxis, a potentially life-threatening condition which requires treatment with epinephrine. Other presentations may include atopic dermatitis or inflammation of the esophagus. Fish is one of the eight common food allergens, responsible for 90% of allergic reactions to foods: cow's milk, eggs, wheat, shellfish, peanuts, tree nuts, fish, and soy beans.

<span class="mw-page-title-main">Shellfish allergy</span> Type of food allergy caused by shellfish

Shellfish allergy is among the most common food allergies. "Shellfish" is a colloquial and fisheries term for aquatic invertebrates used as food, including various species of molluscs such as clams, mussels, oysters and scallops, crustaceans such as shrimp, lobsters and crabs, and cephalopods such as squid and octopus. Shellfish allergy is an immune hypersensitivity to proteins found in shellfish. Symptoms can be either rapid or gradual in onset. The latter can take hours to days to appear. The former may include anaphylaxis, a potentially life-threatening condition which requires treatment with epinephrine. Other presentations may include atopic dermatitis or inflammation of the esophagus. Shellfish is one of the eight common food allergens, responsible for 90% of allergic reactions to foods: cow's milk, eggs, wheat, shellfish, peanuts, tree nuts, fish, and soy beans.

<span class="mw-page-title-main">Sesame allergy</span> Food allergy caused by sesame seeds

Sesame allergy is a common food allergy to foods made with sesame seeds. Prevalence estimates for the allergy are in the range of 0.1–0.2% of the general population, and are higher in the Middle East and other countries where sesame seeds are used in traditional foods.

References

  1. "Drug Allergy". Mayo Clinic.
  2. 1 2 3 4 5 Holgate, Steven. Allergy (4th ed.). Elsevier Saunders. pp. 321–330. ISBN   9780723436584.
  3. "Drug Allergy: An Updated Practice Parameter" (PDF). Retrieved 2013-12-02.
  4. 1 2 Adkinson, Franklin. Middleton's allergy : principles and practice (8 ed.). Saunders Elsevier. pp. 1274–1295. ISBN   978-0-323-08593-9.
  5. "World Allergy Organization" . Retrieved 2013-11-25.
  6. 1 2 3 4 5 6 7 Warrington R, Silviu-Dan F, Wong T (2018). "Drug allergy". Allergy Asthma Clin Immunol. 14 (Suppl 2): 60. doi:10.1186/s13223-018-0289-y. PMC   6157123 . PMID   30275849.
  7. 1 2 Schnyder B (August 2009). "Approach to the patient with drug allergy". Immunol Allergy Clin North Am. 29 (3): 405–18. doi:10.1016/j.iac.2009.04.005. PMID   19563988.
  8. Kemp SF, Lockey RF, Simons FE (July 2008). "Epinephrine: the drug of choice for anaphylaxis-a statement of the world allergy organization". World Allergy Organ J. 1 (7 Suppl): S18–26. doi:10.1097/WOX.0b013e31817c9338. PMC   3666145 . PMID   23282530.