Food Intolerance

Food Allergies

Food Allergies

Peanuts can leave you breathless. Cat dander can lead to itchy eyes, a stuffy nose, coughing and sneezing. And most of us have suffered through those seasonal allergies with horrible pollen counts. Learn more...

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Food Allergies and Intolerances

Do you suspect that something you eat is causing those unusual symptoms you get from time to time Food allergies are relatively rare in adults. They most commonly occur in children, who usually outgrow them over time. Foods that most often cause a true allergic reaction in children include egg whites, shellfish, nuts, and milk. Dairy products can produce stomach cramps, bloating, gas, and diarrhea in adults, but these symptoms most often indicate lactose intolerance, an inability to digest lactose, the sugar that is found in milk and other dairy products. Lactose intolerance is much more common than you may think. Most people (except those of northern European descent) develop lactose intolerance in adulthood because their bodies gradually stop pro ducing lactase, an intestinal enzyme that helps to digest lactose. If you think you may have lactose intolerance, switch to the many low-lactose or lactose-free dairy products that are now available. Lactase also is available over the...

Gender Ethnicracial And Life Span Considerations

Anaphylactic shock can occur at any age and in both men and women, but women seem a little more susceptible than men. Individuals with food allergies (particularly shellfish, peanuts, and tree nuts) and asthma may be at increased risk for having a life-threatening anaphylactic reaction. People at the ends of the lifespan are most at risk. To prevent infants and children from experiencing severe allergic reactions, pediatricians carefully plan vaccines and diet to limit the risk of allergic reaction until a child's immune system is more mature. Severe food allergy is more common in children than in adults, but diagnostic contrast, insect stings, and anesthetics are more common in adults than in children. Teenagers with food allergies and asthma may be at high risk for an allergic reaction because they are more likely to eat outside the home and less likely to carry their medications. Older people also have a great risk of anaphylaxis, and their risk of death is high owing to the...

Discharge And Home Healthcare Guidelines

Provide a complete explanation of all allergic responses and how to avoid future reactions. If the patient has a reaction to a food or medication, instruct the patient and family about the substance itself and all potential sources. If the patient has a food allergy, you may need to include a dietitian in the patient teaching. Encourage the patient to carry an anaphylaxis kit with epinephrine. Teach the patient to administer subcutaneous epinephrine in case of emergencies. Encourage the patient to wear an identification bracelet at all times that specifies the allergy.

Categories of food components

Not enough is known yet about the prevalence of food allergies and intolerances. Estimates vary widely and are unreliable. It is not easy to diagnose a food allergy and to identify the food component provoking the allergic reaction. The same holds for food intolerance. In Chapter 14, the different types of food allergy and food intolerance and the associated problems are discussed.

Therapy Past Present and Future

Below are a few examples of second-line medications for the treatment of constipation. Practitioners should always be ready to use treatments empirically for lactose intolerance when patients continue to complain of cramps or pain even when first-line therapies help the patient to have more frequent bowel movements. In a referral practice, up to 50 of referred patients have lasting relief from sometimes decades of discomfort with the use of daily psyl-lium supplementation and a commercial lactase preparation with meals.

Disorders of the Small Intestine

Lactose intolerance is the inability to digest lactose, the sugar found in milk. It is caused by a deficiency of lactase, the enzyme needed to break down lactose during digestion. Symptoms of lactose intolerance include nausea, cramps, bloating, gas, and diarrhea. In general, symptoms appear about a half hour to 2 hours after a person eats or drinks food that contains lactose. Not all people with lactase deficiency experience symptoms, and the severity of symptoms varies from person to person. The disorder is especially common among adults of Asian, African, and Native American descent. If you regularly experience symptoms of lactose intolerance when you consume dairy products, you may be lactose intolerant. To avoid these symptoms, your doctor may recommend that you consume smaller portions of your favorite dairy foods, eat only those dairy products that contain added lactase, or take over-the-counter lactase supplements (in liquid or tablets). He or she may recommend that you follow...

Primary Nursing Diagnosis

If the patient requires surgery, provide a brief explanation of the procedures and what the patient can expect postoperatively. Have the patient practice coughing and deep breathing, and reassure the patient that postoperative analgesia will be available to manage pain. When the patient returns from surgery, use pillows to splint the abdomen during coughing and deep-breathing exercises. Get the patient out of bed for chair rest and ambulation as soon as the patient can tolerate activity. Notify the physician when bowel sounds resume, and gradually advance the patient from a clear liquid diet to solid food. If the patient experiences any food intolerance at all (nausea, vomiting, pain), notify the surgeon immediately.


Various food allergies have been implicated in MS. Some studies have found that MS is more common in areas with high intakes of dairy products or gluten-containing grains, such as wheat, rye, oats, and barley. As a result, the consumption of dairy products or gluten has been implicated in MS. Other proposed allergic foods have included yeast, mushrooms and other fungi, fermented products (such as vinegar), sugar, potatoes, red meat, fruits, vegetables, caffeine, and tea and other tannin-containing foods.

Specific History

The only provoking factors are ingested foreign substances, which are almost exclusively prescription or proprietary medications. On rare occasions foods are implicated, producing a fixed food reaction. The list of offending agents is extensive. The following list includes the more common offenders, but is not all-inclusive.

Treatment Method

Rare situations occur in which enzyme therapy is used in conventional medicine. These conditions include pancreatitis, cystic fibrosis, and Gaucher disease. An enzyme known as lactase is given for people who cannot tolerate dairy products (lactose-intolerance). People with excessive gas may find relief from Beano, an enzyme (alpha-galactosidase) that improves the digestion of high-fiber foods, such as beans, peas, and whole grains.


A high dietary intake of specific carbohydrates has been reported to affect the health of small groups of the population. The absence of disaccharidases in the brush border of the intestinal mucosa connected with genetic as well as contracted disorders gives rise to absorption disturbances and chronic diarrhea. Deficiencies of the disaccharidases sucrase and maltase are rare. On the other hand, lactase deficiency occurs rather frequently. Symptoms of lactose intolerance are usually mild or absent unless large quantities are taken, e.g., a liter of milk, which contains 50 g of lactose. The cause of lactase deficiency may be of three types. First, there is the rare congenital lactase deficiency, with symptoms showing shortly after birth. Secondly, there is a very common ethnic form which affects a large part of the human population. In Asians and many Africans, the enzyme activity disappears at varying ages between infancy and adultness. Lactase cannot be induced in

Bulking Agents

Fiber supplementation should be foundational therapy for most if not all constipated patients.7 A constipated patient should be started at a relatively low dose and slowly increased to a typical daily dose over several days to 1 week. Starting low will help to decrease bloating. After 2 to 4 weeks on therapy, if the patient is still having symptoms, the dose should be doubled in a split dose. Many patients have relief with fiber alone. Continued problems thereafter can be treated with occasional, mild laxatives. The nonrespon-ders may need the addition of treatment for lactose intolerance, or evaluation to assess for colonic inertia, pelvic floor disorders, or postoperative causes.


Type I (anaphylactic) due to preformed IgE antibodies, which cause release of vasoactive amines (e.g., histamine, leukotrienes) from mast cells and basophils. Examples are anaphylaxis (bee stings, food allergy especially peanuts and shellfish , medications especially penicillin and sulfa drugs , rubber glove allergy), atopy, hay fever, urticaria, allergic rhinitis, and some forms of asthma.


Identification of the allergic child is important in patient evaluation, and a complete medical and family history is the most critical aspect of this process. Symptoms suggestive of allergy include nasal congestion, pruritic nasal and ocular mucous membranes, clear rhinorrhea, paroxysmal sneezing (often exacerbated by inhaled dust or animal exposure), and rhinosinusitis during allergy season.17,27 The history may also include infantile eczema, asthma, food allergy, or a previous good response to antihista-mines or intranasal anti-inflammatory agents.17 Family history is important because children of two allergic parents have a 65 to 75 incidence of significant atopy, and children with one atopic parent have a 35 incidence of allergy.54 The likelihood of allergies is also increased in children with an atopic sibling.54

Anaphylactic Deaths

A fatal anaphylactic reaction results in acute respiratory distress or circulatory collapse. Obstruction of the upper airway can be caused by pharygeal or laryngeal edema of the lower airway, by bronchospasm with contraction of the smooth muscle of the lungs, vasodilation, and increased capillary per-meability.14 Cardiac arrest may be caused by respiratory arrest the direct effects of the chemical mediators of anaphylaxsis on the heart or shock caused by a combination of intravascular fluid loss from edema and vasodilatation. Pumphrey and Roberts studied 56 anaphylactic deaths coming to autopsy.15 They found that, in all 16 deaths that were caused by food allergy, there was difficulty in breathing, with death in 13 of the cases caused by respiratory


Two patients with MCAD deficiency were studied. Patient 1 This female was normal until 15m of age when she presented with a Reye-like syndrome. Diagnosis of MCAD deficiency was established. She survived the initial episode but a severe seizure disorder and cerebral palsy developed. Since diagnosis the patient has been on a diet with 65-67 of total calories given as CHO, 25-27 as fat and 7.5-8 as protein. Due to a partial lactose intolerance, diet was prepared using a lactose free formula (LK Kasdorf, Argentina) mixed with glucose polymers (GP) (Polimerosa Kasdorf, Argentina) or GP plus uncooked corn starch (CS) and was given by nasogastric feeds every 4-6 h. Her studies were performed at age 2y 10m as follows


Some enzymes are employed as human digestive aids to replace or increase endogenous digestive enzymatic activities. Lactase and pancreatic enzyme replacement therapies are two such examples. The enzyme P-D-galactoside-galactohydrolase (EC, commonly known as P-galactosidase or lactase, hydrolyzes lactose, forming glucose and galactose 165 . Lactose, or milk sugar, is a disaccharide found in the milk of most mammals. Lactose is digested in vivo in the gastrointestinal tract by lactase-phlorizin hydrolase, a membrane-bound enzyme of the small intestinal epithelial cells. Intestinal lactase insufficiency results in lactose intolerance (maldigestion with negative clinical symptoms). Intestinal P-galactosidase insufficiency can be a result of downregulation in the expression of the P-galactosidase gene, which is a penetrant autosomal gene located on chromosome Lactose intolerance and infantile colic are two lactose-related conditions whose symptoms can be relieved by dietary...


Elimination of lactose is recommended, as up to 60 of the population in the United States has lactose intolerance and these symptoms can mimic IBS.31 Both caffeinated and decaffeinated coffee have been demonstrated to stimulate motor activity of the rectosigmoid colon in normal volunteers.32 Sorbitol, a sugar alcohol that is a common ingredient of sugar-free candies, medicines, and antacids, may produce bloating, diarrhea, and gas, mimicking IBS. Establishment of exercise and stress management routines is often also recommended. A method for determining whether life stresses, dietary components, and other psychosocial factors exacerbate IBS symptoms involves the use of a symptom diary for 2 to 6 weeks. This may be used to determine if dietary factors and stressful events are associated with worsening of IBS symptoms. These journal entries may then be used for recommending dietary exclusions, stress management, and psychological counseling.2,3

Allergies to Food

A food allergy is a reaction of the immune system to a food or food ingredient that most people find harmless. If you eat a food that produces an allergic reaction, your immune system responds by releasing numerous chemicals that cause allergic symptoms. A food allergy is different from a food intolerance, which does not trigger an immune response. A food intolerance (such as lactose intolerance, see page 266) usually arises from an enzyme deficiency and produces symptoms such as stomach cramps, gas, or diarrhea. Food intolerances are relatively common, but a true food allergy is rare, affecting only about 1 percent of the population. The most common foods that cause allergies in adults are fish and shellfish, eggs, and nuts such as peanuts, walnuts, and pecans. Symptoms of food allergy can include skin reactions such as hives or rashes, nasal congestion, asthma attacks (see page 245) in people who have asthma, and gastrointestinal problems such as nausea, gas, or diarrhea. Because...

Yellow fever vaccine

Immediate hypersensitivity reactions with rash, urticaria or asthma occur in less than 1 per million individuals and usually among those with known egg allergy Serious adverse reactions are extremely rare 22 cases of encephalitis have been reported to WHO since 1945, in relation to over 200 million doses of 17D yellow fever vaccine given worldwide. Most of those affected were children under 4 months of age