Depending on whether the salicylate is a component of food or medicine, salicylate intolerance is a form of food intolerance or of drug intolerance.

Salicylate sensitivity is a pharmacological reaction, not a true IgE-mediated allergy. However, it is possible for aspirin to trigger non-allergic hypersensitivity reactions. About 5–10% of asthmatics have aspirin hypersensitivity, but dietary salicylates have been shown not to contribute to this. The reactions in AERD (Samter's triad) are due to inhibition of the COX-1 enzyme by aspirin, as well as other NSAIDs that are not salicylates. Dietary salicylates have not been shown to significantly affect COX-1.

Samter's triad refers to aspirin sensitivity in conjunction with nasal polyps and asthma.

In various studies, about one half of the patients who seek medical treatment for symptoms of MCS meet the criteria for depressive and anxiety disorders. Because many people eliminate whole categories of food in an effort to reduce symptoms, a complete review of the patient's diet may be needed to avoid nutritional deficiencies.

There are no laboratory or skin testing methods for testing salicylate sensitivity. Provocative challenge is one method of obtaining reliable diagnosis. Provocative challenge is intended to induce a controlled reaction as a means of confirming diagnosis. During provocative challenge, the person is given incrementally higher doses of salicylates, usually aspirin, under medical supervision, until either symptoms appear or the likelihood of symptoms appearing is ruled out.

In response to a WHO call for papers at the 5th Paris Appeal Congress of Environmental Idiopathic Intolerance conference that took place in Belgium on the 18th of May, a report that was generally supportive quoted a number of international practitioners. This was provisionally accepted by the Spanish health ministry, and later found proven by a judge in the case of a plumber in the Province of Castellón

MCS is a diagnosis of exclusion, and the first step in diagnosing a potential MCS sufferer is to identify and treat all other conditions which are present and which often explain the reported symptoms. For example, depression, allergy, thyroid disorders, orthostatic syndromes, lupus, hypercalcemia, and anxiety need to be carefully evaluated and, if present, properly treated. The "gold standard" procedure for identifying a person who has MCS is to test response to the random introduction of chemicals the patient has self-identified as relevant. This may be done in a carefully designed challenge booth to eliminate the possibility of contaminants in the room. Chemicals and controls, sometimes called prompts, are introduced in a random method, usually scent-masked. The test subject does not know when a prompt is being given. Objective and subjective responses are measured. Objective measures, such as the galvanic skin response indicate psychological arousal, such as fear, anxiety, or anger. Subjective responses include patient self-reports. A diagnosis of MCS can only be justified when the subject cannot consciously distinguish between chemicals and controls, and when responses are consistently present with exposure to chemicals and consistently absent when prompted by a control.

A 1999 consensus statement recommends that MCS be diagnosed according to six standardized criteria:

1. Symptoms are reproducible with repeated (chemical) exposures

2. The condition has persisted for a significant period of time

3. Low levels of exposure (lower than previously or commonly tolerated) result in manifestations of the syndrome ("i.e." increased sensitivity)

4. The symptoms improve or resolve completely when the triggering chemicals are removed

5. Responses often occur to multiple chemically unrelated substances

6. Symptoms involve multiple-organ symptoms (runny nose, itchy eyes, headache, scratchy throat, ear ache, scalp pain, mental confusion or sleepiness, palpitations of the heart, upset stomach, nausea and/or diarrhea, abdominal cramping, aching joints).

The College of Optometrists (UK) has specified guidelines for optometrists who use the colorimeter system. A society for coloured lens prescribers has been established to provide a list of eye-care practitioners with expertise in the provision of coloured lenses for the treatment of visual stress.

The Irlen Method uses coloured overlays and tinted lenses in the form of glass or contact lenses. The method is intended to reduce or eliminate perceptual processing errors; it is claimed the resultant retiming of visual signals in the brain improves the reading difficulties associated with scotopic sensitivity syndrome.

Prevention includes avoiding exposure to the sun and wearing sun block on the affected area.

- Cover up: wear long sleeves, slacks, and a wide-brimmed hat whenever harsh exposure is probable

- Avoid chemicals that may trigger a reaction

- Wear sunscreen at least factor 30 with a high UVA protection level

- Wear gloves and/or remain indoors after handling fruits or plants which increase sensitivity to light

Berylliosis is an occupational disease. Relevant occupations are those where beryllium is mined, processed or converted into metal alloys, or where machining of metals containing beryllium and recycling of scrap alloys occurs. It is associated with aerospace manufacturing, microwave semiconductor electronics, beryllium mining or manufacturing of fluorescent light bulbs (which once contained beryllium compounds in their internal phosphor coating). Beryllia was used in lamp manufacture because of ceramic's obvious virtues for insulation and heat resistance, and also because beryllia could be made transparent. Certain welding anodes along with other electrical contacts and even non-sparking tools are made of beryllium copper alloy and the subsequent machining of such materials would cause the disease as well.

There is a great deal of conflicting information regarding the inclusion of oats in a gluten-free diet. Although cross-contamination in the field and during processing partially explains the different reactions that celiacs can have to oats, a recent study indicates that there are also different amounts of avenin present in different cultivars of oat. The G12 antibody used in the study is currently the only one that can reliably distinguish between varieties of oat. Previous studies have indicated both children and adult coeliacs are largely tolerant of oats. Other studies have followed both children and adults for one, two, and five years on the "uncontaminated" oat containing gluten-free diet. These studies failed to show significant changes in intestinal morphology indicative of a relapse of celiac disease. Anti-gliadin and reticulin antibodies as well as numbers of intraepithelial lymphocytes (IELs) did not differ significantly between oat-eating celiacs and non-oat-eating controls in remission. Invitro tests that are sensitive to wheat gluten found that tryptic peptides of avenin could not induce EMA production in supernatant fluid from cultured duodenal mucosa specimen from celiac patients.

Algorithms that successfully predict T cell stimulatory peptides in gluten identified many similar peptides in hordeins and secalins, but not in oat avenins.

The Canadian Celiac Association suggests that adults can consume up to 70g of oats per day, and children up to 25g. However, two studies indicated that celiac adults could consume 93 grams (3.3 ounces) of oats per day. There is no evidence that oats can trigger GSE, only that in a small number of celiacs disease can be sustained or reinitiated by oats once triggered by wheat. A recent paper examining the IEL levels of celiac patients in remission showed a significantly higher number of IELs in oat-eating celiacs. In addition, antibodies to avenin remain low as long as the diet is gluten-free, but higher anti-avenin antibodies can increase with a diet containing wheat.

Some coeliacs respond adversely to oats. Estimates range from 0.5 to 20% of the GSE population. With coeliac disease, non-compliance in attempting to achieve normal intestinal morphology is a risk factor for refractory disease and cancer.

Screening methods for colon cancer depend on detecting either precancerous changes such as certain kinds of polyps or on finding early and thus more treatable cancer. The extent to which screening procedures reduce the incidence of gastrointestinal cancer or mortality depends on the rate of precancerous and cancerous disease in that population. gFOBT (guaiac fecal occult blood test) and flexible sigmoidoscopy screening have each shown benefit in randomized clinical trials. Evidence for other colon cancer screening tools such as iFOBT (immunochemical fecal occult blood test) or colonoscopy is substantial and guidelines have been issued by several advisory groups but does not include randomized studies.

In 2009 the American College of Gastroenterology (ACG) suggest that colon cancer screening modalities that are also directly preventive by removing precursor lesions should be given precedence, and prefer a colonoscopy every 10 years in average-risk individuals, beginning at age 50. The ACG suggests that cancer detection tests such as any type of FOB are an alternative that is less preferred, and if a colonoscopy is declined, the FIT (fecal immunochemical test, or iFOBT) should be offered instead. Two other recent guidelines, from the US Multisociety Task Force (MSTF) and the US Preventive Services Task Force (USPSTF), while permitting immediate colonoscopy as an option, did not categorize it as preferred. The ACG and MSTF also included CT colonography every five years, and fecal DNA testing as considerations. All three recommendation panels recommended replacing any older low-sensitivity, guaiac-based fecal occult blood testing (gFOBT) with either newer high-sensitivity guaiac-based fecal occult blood testing (hs gFOBT) or fecal immunochemical testing (FIT). MSTF looked at six studies that compared high sensitivity gFOBT (Hemoccult SENSA) to FIT, and concluded that there was no clear difference in overall performance between these methods.

The American College of Gastroenterology has recommended the abandoning of gFOBT testing as a colorectal cancer screening tool, in favor of the fecal immunochemical test. Though the FIT test is preferred, even the guaiac FOB testing of average risk populations may have been sufficient to reduce the mortality associated with colon cancer by about 25%. With this lower efficacy, it was not always cost effective to screen a large population with gFOBT.

If colon cancer is suspected in an individual (such as in someone with an unexplained anemia) fecal occult blood tests may not be clinically helpful. If a doctor suspects colon cancer, more rigorous investigation is necessary, whether or not the test is positive.

In 2006, the Australian Government introduced the National Bowel Cancer Program which has been updated several times since; targeted screening will be done of all Australians aged over 50 to 74 by 2017–2018. Cancer Council Australia recommended that FOBT should be done every two years. Gradually government fund disbursement meant that some people are not yet eligible for the national program and should pay for a FOBT by themselves.

The Canadian Cancer Society recommends that men and women age 50 and over have a FOBT at least every 2 years.

In colon cancer screening, using only one sample of feces collected by a doctor performing a digital rectal examination is discouraged.

The use of the M2-PK Test is encouraged over gFOBT for routine screening as it may pick up tumors that are both bleeding and non bleeding. It is able to pick up 80 percent of colorectal cancer and 44 percent for adenoma > 1 centimeter, while gFOBT picks up 13 to 50 percent of colorectal cancers.

There are four methods in clinical use for testing for occult blood in feces. These look at different properties, such as antibodies, heme, globin, or porphyrins in blood, or at DNA from cellular material such as from lesions of the intestinal mucosa.

- Fecal immunochemical testing (FIT), and immunochemical fecal occult blood test (iFOBT). FIT products utilize specific antibodies to detect globin. FIT screening is more effective in terms of health outcomes and cost compared with guaiac FOBT. According to the guidelines of the American College of Gastroenterology, "Annual fecal immunochemical testing is the preferred colorectal cancer detection test." A FIT test detects globin levels in feces at or above 50 nanograms per mL, the established cutoff by the World Health Organization for Colorectal Cancer Screening.

FIT testing has replaced most gFOBT tests as the colon cancer screening test of choice. This methodology can be adapted for automated test reading and to report quantitative results, which are potential factors in design of a widescale screening strategy. The number of fecal samples submitted for FIT may affect the clinical sensitivity and specificity of the methodology.[8] High sensitivity gFOBT tests such as Hemoccult SENSA remains an accepted option;[8] and may retain a role in monitoring gastrointestinal conditions such as ulcerative colitis; however the FIT test is preferred in recent guidelines.

- Stool guaiac test for fecal occult blood (gFOBT): – The stool guaiac test involves smearing some feces onto some absorbent paper that has been treated with a chemical. Hydrogen peroxide is then dropped onto the paper; if trace amounts of blood are present, the paper will change color in one or two seconds. This method works as the heme component in hemoglobin has a peroxidase-like effect, rapidly breaking down hydrogen peroxide. In some settings such as gastric or proximal upper intestinal bleeding the guaiac method may be more sensitive than tests detecting globin because globin is broken down in the upper intestine to a greater extent than is heme. There are various commercially available gFOBT tests which have been categorized as being of low or high sensitivity, and only high sensitivity tests remain an acceptable alternative to FIT testing, which is now the best-practices recommendation in colon cancer screening. Optimal clinical performance of the stool guaiac test depends on preparatory dietary adjustment.

- Stool DNA screening tests look for DNA alterations that have been associated with cancer.

Additional methods of looking for occult blood are being explored, including transferrin dipstick and stool cytology.

A review from 2000 stated that life expectancy was reduced because of a tendency to develop cancer relatively early as well as deaths due to infections related to immunodeficiency.

Photodermatitis, sometimes referred to as sun poisoning or photoallergy, is a form of allergic contact dermatitis in which the allergen must be activated by light to sensitize the allergic response, and to cause a rash or other systemic effects on subsequent exposure. The second and subsequent exposures produce photoallergic skin conditions which are often eczematous.

Typical levels of beryllium that industries may release into the air are of the order of , averaged over a 30-day period, or of workroom air for an 8-hour work shift. Compliance with the current U.S. Occupational Safety and Health Administration (OSHA) permissible exposure limit for beryllium of has been determined to be inadequate to protect workers from developing beryllium sensitization and CBD. The American Conference of Governmental Industrial Hygienists (ACGIH), which is an independent organization of experts in the field of occupational health, has proposed a threshold limit value (TLV) of in a 2006 Notice of Intended Change (NIC). This TLV is 40 times lower than the current OSHA permissible exposure limit, reflecting the ACGIH analysis of best available peer-reviewed research data concerning how little airborne beryllium is required to cause sensitization and CBD.

Because it can be difficult to control industrial exposures to beryllium, it is advisable to use any methods possible to reduce airborne and surface contamination by beryllium, to minimize the use of beryllium and beryllium-containing alloys whenever possible, and to educate people about the potential hazards if they are likely to encounter beryllium dust or fumes. It is important to damp wipe meallographic preparation equipment to prevent accumulation of dry particles. Sectioning, grinding, and polishing must be performed under sufficiently vented hoods equipped with special filters.

On 29 January 2009, the Los Alamos National Laboratory announced it was notifying nearly 2,000 current and former employees and visitors that they may have been exposed to beryllium in the lab and may be at risk of disease. Concern over possible exposure to the material was first raised in November 2008, when a box containing beryllium was received at the laboratory's short-term storage facility.

Two small randomized controlled trials (RCTs) and one larger RCT (86 subjects) tested glutamine in the prevention of platinum treatment-induced neuropathy and showed promise. As of September 2013 a larger, placebo-controlled trial is running.

A 2013 systematic review of the use of acetyl-L-carnitine, glutamine, vitamin E, glutathione, vitamin B6, omega-3 fatty acids, magnesium, calcium, alpha lipoic acid and n-acetyl cysteine as anti-CIPN adjuvants concluded that "currently no agent has shown solid beneficial evidence to be recommended for the treatment or prophylaxis of CIPN."

In a study of patients receiving oxaliplatin treatment, only 4 percent of those also receiving intravenous calcium and magnesium (ca/mg) before and after each oxaliplatin dose had to discontinue treatment due to neurotoxicity, compared to 33 percent who were receiving intravenous placebo; onset of neuropathy was also significantly delayed in the ca/mg patients, and only 22 percent of the ca/mg patients had long-term CIPN of grade 2 or worse compared with 41 percent of those on placebo. Overall, trials of ca/mg infusion suggest there are no serious harmful side effects and it may be an effective preventative therapy — the number of patients so far studied is small, however, and confident conclusions cannot be drawn.

There is no treatment for NBS, however in those with agammaglobulinemia, intravenous immunoglobulin may be started. Prophylactic antibiotics are considered to prevent urinary tract infections as those with NBS often have congenital kidney malformations. In the treat of malignancies radiation, alkylating antineoplastic agents, and epipodophyllotoxins are not used, and methotrexate can be used with caution and, the dose should be limited. Bone marrow transplants and hematopoietic stem cells transplants are also considered in the treatment of NBS. The supplementation of Vitamin E is also recommended. A ventriculoperitoneal shunt can be placed in patients with hydrocephaly, and surgical intervention of congenital deformities is also attempted.

Diagnosis is based on appearance and family history. KID syndrome or keratosis follicularis spinulosa decalvans have some similar symptoms and must be eliminated.

In examining the published studies on opioid-induced hyperalgesia (OIH), Reznikov "et al" criticize the methodologies employed on both humans and animals as being far-removed from the typical regimen and dosages of pain patients in the real world. They also note that some OIH studies were performed on drug addicts in methadone rehabilitation programs, and that such results are very difficult to generalize and apply to medical patients in chronic pain. In contrast, a study of 224 chronic pain patients receiving 'commonly-used' doses of oral opioids, in more typical clinical scenarios, found that the opioid-treated patients actually experienced no difference in pain sensitivity when compared to patients on non-opioid treatments. The authors conclude that opioid-induced hyperalgesia may not be an issue of any significance for normal, medically-treated chronic pain patients at all.

Opioid-induced hyperalgesia has also been criticized as overdiagnosed among chronic pain patients, due to poor differential practice in distinguishing it from the much more common phenomenon of opioid tolerance. The misdiagnosis of common opioid tolerance (OT) as opioid-induced hyperalgesia (OIH) can be problematic as the clinical actions suggested by each condition can be contrary to each other. Patients misdiagnosed with OIH may have their opioid dose mistakenly decreased (in the attempt to counter OIH) at times when it is actually appropriate for their dose to be increased or rotated (as a counter to opioid tolerance).

The suggestion that chronic pain patients who are diagnosed as experiencing opioid-induced hyperalgesia ought to be completely withdrawn from opioid therapy has also been met with criticism. This is not only because of the uncertainties surrounding the diagnosis of OIH in the first place, but because of the viability of rotating the patient between different opioid analgesics over time. Opioid rotation is considered a valid alternative to the reduction or cessation of opioid therapy, and multiple studies demonstrate the rotation of opioids to be a safe and effective protocol.

Diagnosis is usually performed by submitting multiple stool samples for examination by a parasitologist in a procedure known as an ova and parasite examination. About 30% of children with "D. fragilis" infection exhibit peripheral blood eosinophilia.

A minimum of three stool specimens having been immediately fixed in polyvinyl alcohol fixative, sodium acetate-acetic acid-formalin fixative, or Schaudinn's fixative should be submitted, as the protozoan does not remain morphologically identifiable for long. All specimens, regardless of consistency, are permanently stained prior to microscopic examination with an oil immersion lens. The disease may remain cryptic due to the lack of a cyst stage if these recommendations are not followed.

The trophozoite forms have been recovered from formed stool, thus the need to perform the ova and parasite examination on specimens other than liquid or soft stools. DNA fragment analysis provides excellent sensitivity and specificity when compared to microscopy for the detection of "D. fragilis" and both methods should be employed in laboratories with PCR capability. The most sensitive detection method is parasite culture, and the culture medium requires the addition of rice starch.

An indirect fluorescent antibody (IFA) for fixed stool specimens has been developed.

1. One researcher investigated the phenomenon of symptomatic relapse following treatment of infection with "D. fragilis" in association with its apparent disappearance from stool samples. The organism could still be detected in patients through colonoscopy or by examining stool samples taken in conjunction with a saline laxative.

2. A study found that trichrome staining, a traditional method for identification, had a sensitivity of 36% (9/25) when compared to stool culture.

3. An additional study found that the sensitivity of staining was 50% (2/4), and that the organism could be successfully cultured in stool specimens up to 12-hours old that were kept at room temperature.

Many people remove gluten from the diet after a long history of health complaints and unsuccessful consultations with numerous physicians, who simply consider them as suffering from irritable bowel syndrome, or even before seeking medical attention. This fact can diminish the CD serological markers titers and may attenuate the inflammatory changes found in the duodenal biopsies. In these cases, patients should be tested for the presence of HLA-DQ2/DQ8 genetic markers because a negative HLA-DQ2 and HLA-DQ8 result has a high negative predictive value for celiac disease. If these markers are positive, it is advisable to undertake a gluten challenge under medical supervision, followed by serology and duodenal biopsies. However, gluten challenge protocols have significant limitations, because a symptomatic relapse generally precedes the onset of a serological and histological relapse, and therefore becomes unacceptable for many patients. Gluten challenge is also discouraged before the age of 5 years and during pubertal growth.

It remains unclear what daily intake of gluten is adequate and how long the gluten challenge should last. Some protocols recommend eating a maximum of 10 g of gluten per day for 6 weeks. Nevertheless, recent studies have shown that a 2-week challenge of 3 g of gluten per day may induce histological and serological abnormalities in most adults with proven celiac disease. This new proposed protocol has shown higher tolerability and compliance. It has been calculated that its application in secondary-care gastrointestinal practice would identify celiac disease in 7% of patients referred for suspected NCGS, while the remaining 93% would be confirmed as NCGS; this is not yet universally adopted.

For people on a gluten-free diet who are unable to perform an oral gluten challenge, an alternative to identify possible celiac disease is an in vitro gliadin challenge of small bowel biopsies; this test is only available at selected specialized tertiary-care centers.

Evaluating the presence of antigliadin antibodies (AGA) can be a useful complementary diagnostic test. Up to 50% NCGS patients may have elevated AGA IgG antibodies, but rarely AGA IgA antibodies (only 7% of the cases). In these patients, unlike in celiac disease people, the IgG AGA became undetectable within 6 months of using a gluten-free diet.

A literature review of 2014 found that non-coeliac gluten sensitivity diagnosis can be reached only by excluding celiac disease (CD) and wheat allergy.

Persons suspected of having celiac disease may undergo serological testing for IgA anti-tissue transglutaminase antibodies (abbreviated anti-tTG antibodies or anti-TG2 antibodies) and anti-endomysial antibodies (abbreviated EMA) provided the IgA-level is high, and if IgA is low, testing for certain IgG antibodies; in case of positive serological indication, a duodenal biopsy may confirm active celiac disease.

Eliminating the possibility of CD can generally also be done by adding HLA-DQ typing. The absence of HLA-DQ2 and HLA-DQ8 has a very high negative predictive value for CD, and the predictive value can be further enhanced by including HLA-DQ7.5 (HLA-DQ2 and HLA-DQ8 are found in coeliac disease 98% of the time in Caucasians, HLA-DQ7.5 present in the remaining 1.6% and only 0.4% of Caucasians are missed with the combination of these 3). Without serological or HLA-DQ2/8 positivity, celiac disease is likely not present. HLA-DQ typing has a practical advantage in that it is the only diagnostic test that allows to exclude CD when a patient is already on a gluten-free diet; however, as not only celiacs are HLA-DQ2/HLA-DQ8 positive, this method has a higher false positive rate than anti-TG2 and EMA antibody testing.

A four-of-five rule was proposed 2010 for confirming celiac disease, with the disease confirmed if at least four of the following five criteria are satisfied:

- typical symptoms of celiac disease;

- positivity of serum celiac disease immunoglobulin, A class autoantibodies at high titer;

- human leukocyte antigen (HLA)-DQ2 or DQ8 genotypes;

- celiac enteropathy at the small bowel biopsy; and

- response to the gluten-free diet.

For diagnosis of wheat allergy, allergy tests are available.

Treatment of opioid tolerance and Opioid-Induced Hyperalgesia (OIH) differs but it may be difficult to differentiate these two conditions in a clinical setting where most pain assessments are done through simple scale scores. The treatment for OIH may be challenging because an inadequate number of quality studies exists possibly due to the complexity in diagnosis of OIH and challenges in working with patients on chronic opioids. Currently there is no single best treatment method for OIH and clinicians are advised to choose an appropriate therapy based on the unique clinical scenario and history of each patient.

One general treatment option is to reduce or discontinue the dose of opioid to see if OIH is improved. Opioid sparing or opioid switching, which is replacing the current opioid with another pharmacological agent such as morphine or methadone, has been reported to be effective in some studies but this may also increase the sensitivity to pain according to some case reports. Ketamine, a NMDA antagonist, has been shown to prevent the extended use of opioid in post-operative hyperalgesia when it is infused in a small amount perioperatively along with the opioid but there are also studies that show ketamine being ineffective in modulating hyperalgesia. Addition of the NSAID, especially some COX-2 inhibitors, or acetaminophen is also suggested as a possible treatment option.

A study found that, "Increasing but moderate alcohol consumption in women was determined to be associated with an increased risk of cancers of the oral cavity and pharynx, esophagus, larynx, rectum, breast, and liver…".