INTRODUCTION — The primary therapeutic strategy in the management of food allergy is avoidance of the culprit allergen. Complete avoidance is typically prescribed for immunoglobulin E (IgE)-mediated food allergies as well as food-protein enterocolitis in infants. (See "Food protein-induced allergic proctocolitis of infancy".)
Successful allergen avoidance is straightforward in theory. However, in reality, avoidance requires extensive patient education. Clinicians should know how to instruct patients to read labels on packaged foods, prepare safe meals at home, and avoid food allergens in restaurant meals. Unintended exposure through cross-contact of foods in a variety of settings must be avoided. Food ingredients may be components of nonfood items, such as medications and vaccines. They may also be incorporated into substances that are inadvertently ingested, such as cosmetics and children's crafts. Lastly, exposure to allergen-containing saliva may occur during kissing or sharing of utensils. This topic review will present each of these issues individually.
The management of food allergy in daycare, schools, and camp settings is presented separately. (See "Food allergy in schools and camps".)
GENERAL CONSIDERATIONS — Patients with food allergy are typically instructed to practice strict avoidance. However, most patients attempting to eliminate a certain food from the diet will not be entirely successful, despite best efforts [1,2]. Thus, patients must be prepared to treat an unexpected reaction at all times and in any setting.
How strict must avoidance be? — Strict avoidance is recommended for most patients with food allergy. However, thresholds of clinical reactivity vary dramatically among allergic individuals and can also vary depending upon how the food is processed. (See "Food allergens: Clinical aspects of cross-reactivity" and "Pathogenesis of food allergy" and "Molecular features of food allergens".)
Important observations about avoidance include the following:
●Studies indicate that less than a milligram of milk, egg, or peanut can induce symptoms in some highly sensitive individuals, while others may not experience a reaction until more than 10 grams have been ingested [3-7].
●Clinical experience and observational studies show that some individuals with egg or milk allergy tolerate these foods in low amounts and as minor ingredients baked into products, such as cakes or cookies. (See "Egg allergy: Management", section on 'Extensively heated (baked) HE' and "Milk allergy: Management", section on 'Extensively heated (baked) cow's milk'.)
●Certain types of mild allergy may not require strict avoidance, such as the pollen-food related syndrome or oral allergy syndrome [8]. (See "Management and prognosis of oral allergy syndrome (pollen-food allergy syndrome)", section on 'Avoidance'.)
Thus, clinician experience and discretion is needed to tailor avoidance recommendations to the patient's specific situation and degree of sensitivity.
Skin contact and inhalation — Food-allergic reactions generally occur following ingestion. Other routes of exposure, such as skin exposure or inhalation, are unlikely to cause significant reactions [1]. Even in the most highly sensitive individuals, these types of exposure appear to cause very limited reactions [9,10]. The most likely explanation for reactions that appear to occur in the absence of ingestion is inadvertent contact with the food and subsequent transfer of allergen from the hands to the mouth or other mucosal tissues.
A small number of studies directly investigated the effects of noningestion exposures to peanut, with reassuring results:
●One study applied a gram of peanut butter for 15 minutes to the skin of 281 children who were skin prick-test positive to peanut [11]. The challenge was considered positive if one or more wheals (urticaria) were present when the peanut butter was removed, and 41 percent of tests were positive. No child experienced a systemic reaction. A subset of children with either positive or negative contact tests then underwent blinded, placebo-controlled, oral challenges. In the contact-positive group, 82 percent of children reacted to ingesting peanut, while, in the contact-negative group, 50 percent reacted. Thus, contact urticaria to peanut is not uncommon among peanut-allergic children and may be more likely in highly reactive children. However, no systemic reactions occurred during the 15-minute skin exposure.
●In another double-blind, placebo-controlled study, 30 children with histories of severe reactions to peanut ingestion were challenged by close proximity/smelling peanut butter [9]. A 6-inch square area of peanut butter hidden with sheer gauze was placed 12 inches from the children's faces for 10 minutes. No child experienced symptoms from proximity/smelling of peanut butter, although one experienced throat symptoms during exposure to placebo (presumably from anxiety).
The inhalation of aerosolized food proteins can result in contact between food matter and the respiratory mucosa (nasal or pulmonary). Aerosolization of food can occur as a result of cooking or processing (eg, boiling, frying, grating, shredding, grinding). However, the odor of food does not indicate the presence of relevant proteins. Regarding peanut, this is demonstrated in the study above [9], and several studies have failed to detect peanut in the air near peanut butter or when peanuts are being shelled or manipulated in other ways [12-14].
During aerosolization, actual food matter, including proteins, may become airborne. This is critical because all identified food allergens are proteins, and these proteins are the necessary inciting agents of allergic reactions. Inhalation contact with aerosolized food has been shown to be capable of inducing asthmatic or respiratory reactions in highly sensitive individuals [10,15]. To avoid respiratory reactions, highly sensitive individuals should avoid situations in which aerosolized food could be inhaled, including proximity to steam and vapors from cooking, or proximity to an activity involving chopping, grinding, or vigorously manipulating the culprit food.
Maternal dietary avoidance of allergens for infants with proven food allergy — Food allergens ingested by the mother can be detected in breast milk, with individual variability [16-18]. A study in which 23 women ingested 50 g of dry-roasted peanut found that peanut protein was detectable in 11 (48 percent) participants, with a median peak protein concentration of 200 ng/mL [16]. There are case reports and case series indicating that allergic reactions, including anaphylaxis, can occur in the infant from transfer of maternally ingested allergen through breast milk [17,19-21]. There is also evidence that infants may have chronic atopic dermatitis or gastrointestinal symptoms (vomiting, diarrhea, failure to thrive, proctocolitis) triggered by food allergens in breast milk [17,22,23]. Food protein-induced enterocolitis syndrome triggered by allergen in breast milk is also possible, although rare [24,25]. (See "Food protein-induced enterocolitis syndrome (FPIES)".)
When a breastfed infant is diagnosed with an allergy to a specific food, the infant must avoid direct ingestion of the allergen. Options regarding the maternal diet include strict avoidance, reduced ingestion, no avoidance, or, for milk and egg, ingestion of only extensively heated forms (eg, bakery goods) that appear to have reduced allergenicity [26,27]. An alternative option is the cessation of breastfeeding [22]. There are no controlled trials upon which to base recommendations about maternal avoidance, and strict avoidance could be recommended in all circumstances.
Maternal dietary allergen avoidance while breastfeeding an infant with food allergy has been suggested if symptoms are attributable to the mother's diet [28,29]. However, arguments against strict maternal avoidance, if there are no apparent ill effects on the infant during maternal consumption, include improved maternal/infant nutrition and quality of life. Additionally, there is a lack of data on whether allergens in breast milk are tolerizing or sensitizing for the infant. (See "Primary prevention of allergic disease: Maternal diet in pregnancy and lactation".)
We generally recommend strict maternal dietary avoidance if the infant had an acute reaction to an allergen in breast milk, a severe anaphylactic reaction to an allergen the infant ingested directly, chronic symptoms attributable to the food despite a low maternal intake of the trigger, or a reaction to a food that often triggers severe reactions and is generally eaten by the mother in larger quantities during meals (eg, peanut, nuts, fish, shellfish).
We discuss the option of allowing reduced maternal intake of the allergen (at or below amounts ingested prior to diagnosis or, for milk or egg, using baked forms) when the breastfed infant had no history of chronic symptoms prior to the diagnosis of food allergy or when maternal dietary allergen reduction resolves mild chronic symptoms. In one study of infants with cow's milk allergy, the median dose of milk ingested by the mother that elicited symptoms, primarily flaring of eczema, in the breastfed infant was 700 mL [17].
When mothers follow avoidance diets, nutritional issues should be addressed. (See "Management of food allergy: Nutritional issues".)
SKILLS FOR DAILY LIVING — Patients and parents must become proficient in label reading, meal preparation, and, if the patient eats in restaurants, communicating their needs to the staff. Consultation with a registered dietitian can be helpful in developing a plan for food allergen avoidance and preventing dietary deficiencies, especially in children with multiple food allergies [30].
Food labeling — Laws regarding what a manufacturer is required to present on an ingredient statement of a prepared food vary by country [31]. Concerns for a food-allergic consumer include:
●Disclosure of all ingredients
●Disclosure of potential cross-contact of allergen with the final food product
●Manufacturing procedures that provide consistent ingredients (eg, no inadvertent inclusion of an undisclosed allergen)
Legislation in the United States — In the United States, the Food Allergen Labeling and Consumer Protection Act (FALCPA) of 2004 is a law requiring that the eight major allergens or allergenic food groups (milk, egg, fish, crustacean shellfish, tree nuts, wheat, peanut, and soy) be declared on ingredient labels using these plain English words. These allergens must be listed if they are present as an ingredient in any amount. The plain English words used to identify the foods may be placed within the ingredient list or as a separate "contains" statement. The law also requires that the specific type of allergen within a category be named, such as hazelnut or walnut, in addition to "tree nuts."
FALCPA applies to foods manufactured in the United States, as well as packaged foods that are imported for sale and subject to US Food and Drug Administration (FDA) regulation. FALCPA applies to all types of packaged foods except for meat, egg, and poultry products and raw agricultural foods, such as fruits and vegetables in their natural state.
Previously, foods could be labeled only with scientific or nonspecific terms (eg, casein or "natural flavor" for milk). Patients had to be aware of all of the terms that could be used to refer to a common food (Food Allergy Research and Education [FARE]). The law still allows the use of such terms, although plain English must also be present. FALCPA only applies to the eight major allergens listed here. Other allergens, such as garlic or sesame, may still be listed using ambiguous terms, such as "spice." In some cases where ambiguous terms remain, a consumer may need to call the manufacturer to clarify ingredients. In regards to soy, terms such as soybean, soy, and soya are considered interchangeable. For seafood, FALCPA requires the identification of finned fish and crustacean shellfish (eg, lobster, shrimp, crab), although noncrustaceans, such as squid or mollusks (eg, clams, mussels, oysters), do not have to be identified. (See "Seafood allergies: Fish and shellfish".)
The FALCPA legislation does not define a safe threshold of included allergens, and several food ingredients may now be included on labels that did not previously disclose them. Processing aids, such as soy lecithin, a fatty derivative of soy that contains a very small amount of soy protein, may now appear as "soy" (see 'Medications and asthma inhalers' below). The law acknowledges that certain forms of highly processed oils may not contain any appreciable protein, for example, soy oil.
FALCPA can be revised by allowed petition. The US FDA announced voluntary guidance in late 2020 encouraging food manufacturers to declare sesame on food labels [32]. Legislative efforts are also underway in the House and Senate to include sesame as an allergen that must be declared on food labels as part of the Food Allergy Safety, Treatment, Education, and Research (FASTER) Act. Updates are available from the Center for Food Safety and Applied Nutrition, a branch of the US FDA [33].
Legislation in other countries — Other countries are addressing issues of food labeling as well [34]. The European Union includes all of the US foods and adds sesame, mollusks, mustard, celery, and lupine; Australia includes the US foods and adds gluten and sesame; Japan requires labeling specifically for milk, egg, shrimp, crab, peanut, wheat, and buckwheat but "recommends" declaring 18 additional foods, among them salmon, walnut, soy, and gelatin.
Advisory labeling — Certain phrases are used by the food industry when a particular allergen is not an intended ingredient of the food but rather may contact or become a part of the food despite accepted manufacturing processes. Various terms are used for advisory labeling, including "may contain," "processed in a facility with," "manufactured on shared equipment with," and others. These terms are applied at the discretion of the manufacturer. We advise patients to avoid foods that include a culprit allergen in an advisory statement because it is impossible for the consumer to determine the actual risk, and serious reactions from cross-contact have been reported [2].
Advisory labeling is common. An extensive audit of 20,241 supermarket products found that 17 percent had advisory labeling [35]. Consumers often misunderstand advisory labels; some may consider them mandatory (they are not), and some may ignore them, believing they can infer risk based upon the wording or consider the warning to be for legal purposes rather than a reflection of a tangible risk [36,37].
A study of over 600 consumers who shop for persons with food allergies showed that significantly fewer were avoiding products with advisory labels in 2006 than in 2003 [36]. Shoppers judged risk based upon label terminology. As an example, they were more likely to purchase products labeled "made in a facility that processes peanut" than those labeled "may contain peanut" when shopping for a peanut-allergic patient. However, assays of a sample of 179 products with advisory labeling for peanut disclosed that 7 percent of the products contained detectable peanut protein regardless of how the warning was stated. Thus, consumers are increasingly taking risks and falsely assuming that the label terminology reflects the risk level.
Another study examined products with milk-advisory labeling [38]. Detectable milk was found in 34 of 81 (42 percent) of these products, a much higher frequency than similar studies of peanut. The study included 18 dark chocolate products, 78 percent of which had detectable milk protein. Estimates of the doses of milk that might be ingested in a normal serving size of these milk-contaminated products ranged from 0.027 to 620 mg of milk.
In a study of a selection of 401 products from among types having a higher rate of advisory labeling (baking and pancake mixes, chocolate and nonchocolate candies, cookies, salty snacks, cold cereals, and pastas), 3 of 26 products labeled as using "Good Manufacturing Practices" had detectable levels of unintended allergens (all from one supermarket chain) [39]. Overall, contamination with an allergenic food (milk, egg, or peanut) was seen in 5.3 percent of products with advisory statements and in 1.9 percent of similar products without this labeling. Contaminated products were more commonly from small (5.1 percent) rather than large (0.75 percent) companies.
In another study, culprit food products that were suspected to have triggered reactions in adults with food allergies were analyzed for the presence of common allergens [40]. Out of 51 reactions reported with food available for testing, 20 percent of food products did not have advisory labeling but did contain at least one undeclared allergen (33 percent of products without advisory labeling). Of the 21 food products with advisory labeling, 43 percent had allergens detected. In a few instances, the allergen detected was not included in the ingredient list or advisory label. A wide range of products were implicated in the accidental allergic reactions. Contamination rates were highest for peanut, milk, and sesame.
Certain groups of patients with food allergy are less likely to heed advisory labeling, specifically teenagers and young adults. In a study of 174 adolescents and young adults with food allergy, 42 percent were willing to eat foods labeled "may contain" an allergen [41].
Alcoholic beverages — Patients in the United States should be aware that alcoholic beverages may also contain allergens, including unexpected ones such as eggs, cow's milk, and seafood (used as clarifying agents). FALCPA does not cover alcoholic beverages. For persons in the European Union, the European Food Safety Authority has exempted fermentation substrates and their products, including bacterial cultures and enzymes, from labeling laws [42]. At least two small studies concluded that the use of allergenic foodstuffs as clarifying agents in wine did not result in clinically significant reactions in patients allergic to the food in question, even when prick skin tests to the wine were positive [43,44]. Allergic reactions to beer appear to be rare [45].
Home-meal preparation — Some families avoid bringing food into the home to which one member is allergic, while others keep the food in the house and avoid cross-contact. Principles of avoidance of cross-contact must be reviewed carefully with patients/families. Utensils, cookware, glassware, storage containers, and other food preparation materials in contact with an allergen should not be used to prepare or serve "safe" meals, unless thoroughly cleaned first. Alternatively, the safe meal can be prepared first as a matter of routine before other food. Additional tips include keeping food containers covered to prevent spill contamination and designating specific containers of food for use by the allergic person only.
Vigilance for cross-contact must be practiced by everyone in the family, including other small children. For example, a knife used to prepare peanut butter and jelly by a nonallergic child could introduce peanut allergen into otherwise safe jelly and subsequently cause a reaction in a peanut-allergic sibling eating the jelly.
Cleaning — Although only investigated for peanut butter, cleaning tabletops with several standard cleansers was sufficient for removal of peanut allergen [12]. Household cleaners (with the exception of dishwashing liquid) and commercial wipes effectively removed peanut allergen from table tops. Both liquid or bar soap, but not alcohol-based antibacterial gels, removed peanut allergen from adults' hands. This study is reviewed in more detail elsewhere. (See "Food allergy in schools and camps".)
Restaurant meals — A study of persons with peanut and tree nut allergies revealed that certain restaurants or food services were high risk: ice cream parlors, bakeries, and Asian restaurants [46]. These types of restaurants frequently use peanut/nut ingredients and are prone to cross-contact. Similarly, persons with a seafood allergy would likely have more difficulty obtaining a safe meal from a restaurant that specializes in seafood. Buffet services should be avoided due to the risk of cross-contact. Additional problems identified are listed in the table (table 1).
One study administered telephone questionnaires to 100 individuals (including managers, servers, chefs, and other personnel) employed in various restaurants and food establishments in the New York City area [47]. Five true-or-false questions about food allergy were presented, and only 22 percent of respondents answered all five correctly. Despite this, approximately 50 percent of respondents felt "very comfortable" that they could provide a safe meal to a food-allergic customer. A British study found a similar disconnect between restaurant staff knowledge and comfort level in providing safe meals to those with food allergy [48]. Patients should not assume that restaurant personnel understand food allergy or know what steps must be taken to guarantee that a meal is safe.
Consumers should identify that they have an allergy (not just distaste for the food) to those who are directly responsible for preparing the meal (ie, the cook, rather than the waitstaff). We suggest discussing hidden ingredients and cross-contact with the restaurant staff to ensure that they do not have misconception, as noted in the study mentioned above. It is helpful to carry a supply of pre-printed cards with clear information about which foods cannot be eaten and a reminder that cooking containers and serving utensils cannot be contaminated with the allergenic food. As an example, it may be necessary to prepare food in cleaned pans and glassware rather than to use shared grills or blenders. Deep fryers, in which oil is reused for frying different foods, should be avoided as the oil easily becomes contaminated with protein from previously cooked foods. Ingredient lists on menus should not be trusted at face value, and the absence of allergens should be verified for any dish ordered.
Airline travel — Allergic reactions to peanut and tree nuts have been reported on commercial airliners [49-52]. Studies of these events have relied upon self-reported reactions to ingestion, skin contact, and inhalation. The degree of risk is difficult to ascertain from these studies. One small study taking air and surface samples in an airplane found that relevant levels of peanut protein were not detectable in the air [53]. Relevant levels were detectable in surface samples (ie, tray table) but in very low amounts (ie, protein from the entire wiped surface of the tray table would need to be consumed to trigger a reaction), except when visible peanut was noted. Travelers with food allergies should avoid eating potentially unsafe airline foods. Those traveling with young children may wish to clean tray tables and inspect seating areas for residual foods that might be ingested by toddlers. Some airlines may provide additional accommodations when requested in advance (eg, a flight where peanuts are not served).
FOOD ALLERGENS IN NONFOOD ITEMS — Consumers with food allergy should be instructed that nonfood items may contain food ingredients, such as medications, vaccines, cosmetics, craft supplies, and sports equipment. Labeling laws do not apply to these products.
Vaccines — Consumers and clinicians should be aware that vaccines can contain food allergens, including egg, chicken, cow's milk, and gelatin proteins. The evaluation and management of allergic reactions to vaccines are presented in more detail separately. (See "Allergic reactions to vaccines" and "Influenza vaccination in individuals with egg allergy".)
Medications and asthma inhalers — Over-the-counter and prescription medications in tablet and capsule form, some inhaled medications for asthma, and some brands of injectable glucocorticoids can also contain food allergens [54]. Several examples are reviewed below.
Lactose — Lactose is a milk sugar derived from milk that is used in many dry-powder inhalers (DPIs), some brands of oral and injectable glucocorticoids, and a few oral medications that are commonly used in atopic patients. Pharmaceutical-grade lactose is considered to contain very little to no milk protein, on the order of a few parts per million. However, possible reactions in children with severe milk allergy have been reported, and small amounts of milk proteins have been detected in various DPI devices [55], lactulose solution, and injectable methylprednisolone (Solu-Medrol 40 mg/mL) [56,57]. We prefer lactose-free preparations or metered-dose inhalers (MDIs) (which use liquid medications and propellants) for patients with asthma and milk allergy. We also avoid, when practical, other lactose-containing medications (eg, the soluble tablet formulation of lansoprazole, chewable cetirizine, and the 10 mg formulation of montelukast) in highly milk-allergic patients for the same reason.
Lipid emulsions — Propofol is formulated in a fat emulsion containing soybean oil and egg lecithin and may contain small amounts of soy or egg protein. The package insert still indicates that it is contraindicated in patients with soy or egg allergy. However, published data suggest that the majority of such patients tolerate propofol uneventfully, and most reactions to propofol occur in patients without such allergies [54,58-66]. Thus, while no special precautions are recommended for the administration of propofol to most patients with soy or egg allergy, use of an alternate anesthetic or a small trial dose of propofol prior to full dose administration is an option for those patients with more severe soy or egg allergy.
Data regarding hypersensitivity to intravenous fat emulsions that contain egg lecithin and soybean oil (ie, intralipid used in total parenteral nutrition) are limited to only a few case reports [67], but confirmatory testing for egg allergy was documented in only one pediatric case [68]. This two-year-old child experienced diffuse pruritus without urticaria on the 14th day of administration. Since alternative preparations of intralipids without egg are not available and reactions are uncommon, intralipids can be given to persons with egg and/or soy allergy of any severity with appropriate caution if clinically indicated.
Egg lysozyme — Lysozyme, an enzyme found in egg white, is used in pharmaceutical products. Severe acute hypersensitivity reactions to lysozyme have been reported [69].
Cosmetics, crafts, and other sources — Various cosmetics may contain a variety of food-derived ingredients [70,71]. Milk, nut oils, wheat, and soy may be used in cosmetics. Children's craft items such as modeling dough may contain wheat. Sometimes egg white is used to smooth finger paints, and chalk may contain casein [72]. Shea nut butter, which is used in cosmetics, baby care products, food, and candy, does not appear to have residual proteins and should be safe [73].
Food allergens can sometimes appear in unexpected places. A young girl with a severe milk allergy experienced life-threatening anaphylaxis involving cardiac arrest immediately following initial use of a pair of boxing gloves. Natural rubber latex was initially suspected as the allergen source, but the culprit was eventually found to be casein protein in the padding of the glove, which was aerosolized when the glove was used in punching [74].
INTERPERSONAL CONTACT — A source of unintended and unexpected allergen exposure is through saliva or other bodily fluids from an individual who recently ingested an allergen.
Saliva — Food-allergic individuals should be warned that exposure may occur through kissing, as well as sharing straws, glasses, or utensils. Kissing, in particular passionate kissing, is a relatively common route of exposure. Of 379 allergy patients in the United States with peanut, tree nut, legume, or seed allergy, over 5 percent reported reactions from kissing [75]. Of 839 food allergy patients in Denmark, 16 percent reported reactions after kissing [76].
A study was undertaken to determine the time course of peanut protein (a marker protein Ara h 1) in saliva after a meal of peanut butter and possible methods for reducing levels [77]. Detection of Ara h 1 in saliva was performed by a monoclonal-based enzyme-linked immunosorbent assay (ELISA; detection limit, 15 to 20 ng/mL). Most (87 percent) subjects with detectable peanut after a meal had undetectable levels by one hour with no interventions. None had detectable levels several hours later following a subsequent peanut-free lunch.
In the same study, various immediate interventions following a peanut butter meal were assessed, including immediate brushing, prolonged rinsing, both, waiting an hour then brushing, or waiting 30 minutes then chewing gum [77]. None of these interventions consistently resulted in undetectable levels, although levels were lower than might usually be expected to trigger a reaction (below 17 micrograms of peanut protein in 5 mL of saliva). The immediate interventions led to undetectable levels in only one-in-five subjects. However, methods which included a waiting period reduced salivary allergen to undetectable levels in 8-of-10 (wait-brush) and 8-of-9 (wait-gum) subjects. The studies were performed with peanut butter, and results may vary with other allergens or forms of peanut. There is one case report of a mild reaction to peanut despite a two-hour wait, brushing teeth, and chewing gum [78].
In summary, allergen exposure through contact with saliva from another person who has recently ingested the food is possible. Waiting several hours and then eating other foods appears to be more reliable in reducing salivary allergen levels than attempts to cleanse the mouth immediately after allergen ingestion.
Other bodily fluids — Food-allergic reactions from blood transfusion [79] or semen are theoretically possible, although not commonly observed. Possible explanations include the reduction of plasma fractions in blood prepared for transfusion and likely avoidance by partners of large amounts of the allergen proximate to intimate contact.
SOCIETY GUIDELINE LINKS — Links to society and government-sponsored guidelines from selected countries and regions around the world are provided separately. (See "Society guideline links: Food allergy".)
INFORMATION FOR PATIENTS — UpToDate offers two types of patient education materials, "The Basics" and "Beyond the Basics." The Basics patient education pieces are written in plain language, at the 5th to 6th grade reading level, and they answer the four or five key questions a patient might have about a given condition. These articles are best for patients who want a general overview and who prefer short, easy-to-read materials. Beyond the Basics patient education pieces are longer, more sophisticated, and more detailed. These articles are written at the 10th to 12th grade reading level and are best for patients who want in-depth information and are comfortable with some medical jargon.
Here are the patient education articles that are relevant to this topic. We encourage you to print or e-mail these topics to your patients. (You can also locate patient education articles on a variety of subjects by searching on "patient info" and the keyword(s) of interest.)
●Beyond the Basics topic (see "Patient education: Food allergen avoidance (Beyond the Basics)")
SUMMARY
●Once a diagnosis of food allergy is made, education of patients (and families) about avoidance is a crucial therapeutic intervention. Strict avoidance is simple in theory and difficult in practice. (See 'Introduction' above.)
●The vast majority of serious allergic reactions follow ingestion of food. Skin contact may cause local cutaneous symptoms, and inhalation may cause rhinitis and asthmatic symptoms. Simply smelling food is not associated with allergic reactions. (See 'General considerations' above.)
●Labeling laws vary by country. As of January 2006, in the United States, legislation requires declaration of eight "major allergens" in plain English: milk, egg, fish, shellfish, tree nuts, wheat, peanut, and soy. However, all other ingredients may still be listed using ambiguous terms, such as "natural flavor" or "spices" (see 'Food labeling' above). Links to lists of terms used for these common allergens are provided (Food Allergy Research and Education [FARE]). Similar laws are in effect for countries in the European Union.
●Preparation of allergen-free meals for a family where some members continue to eat the allergenic food requires education about cross-contact, safe storage, and cleaning procedures. (See 'Skills for daily living' above.)
●Obtaining safe restaurant meals requires a direct conversation between the consumer and the person preparing the meal. Patients need to report which foods they cannot eat and the need to avoid cross-contact with the allergen during preparation and serving. Cards pre-printed with the critical information can be handed to the cook to reinforce verbal instructions. (See 'Restaurant meals' above.)
●Medications, vaccines, cosmetics, and craft items are other unexpected sources of exposure. (See 'Food allergens in nonfood items' above.)
●Allergic reactions may result from exposure to the saliva from another person who has recently ingested an allergenic food through sharing utensils and intimate kissing. To lower salivary allergen levels, waiting several hours and eating other foods is more effective than immediate interventions like brushing teeth or chewing gum. Reactions resulting from other forms of intimate contact are rarely reported. (See 'Interpersonal contact' above.)
