Cashew

Dosage for Cashew allergenic extracts is highly individualized and must be performed under the direct supervision of an allergist or immunologist.

Diagnostic Skin Prick Testing (SPT)

For adults, the standard procedure involves applying one drop of the 1:10 or 1:20 w/v extract to the skin (usually the forearm or back). A sterile lancet is then used to prick the skin through the drop. A positive control (histamine) and a negative control (saline/glycerin) are always used simultaneously. The results are read after 15 to 20 minutes.

Intradermal Testing

If the SPT is negative but a strong clinical suspicion of allergy remains, a healthcare provider may perform intradermal testing. This involves injecting 0.02 mL to 0.05 mL of a highly diluted extract (often 1:100 to 1:1000 of the SPT concentration) into the dermis. This method carries a higher risk of systemic reactions and is used less frequently for food allergens than for environmental allergens.

Cashew extract is frequently used in pediatric populations, as cashew allergy often manifests in early childhood.

• Infants and Children: The skin prick testing procedure is identical to that of adults, though the back is often the preferred site due to larger surface area.
• Dosage Adjustments: No specific dosage adjustment is required for the extract itself, but the clinician must exercise extreme caution. According to the American Academy of Pediatrics (AAP), skin testing can be performed at any age, but the reactivity of the skin may be lower in infants under 6 months old.

Renal Impairment

No dosage adjustments are typically necessary for diagnostic skin testing in patients with renal impairment, as systemic absorption is minimal. However, if using cashew-based lipid emulsions for parenteral nutrition, renal function must be monitored to ensure clearance of lipid metabolic byproducts.

Hepatic Impairment

Similar to renal impairment, hepatic dysfunction does not alter the protocol for skin testing. In the context of oral immunotherapy, severe hepatic impairment might theoretically affect the metabolism of certain cashew components, but clinical data in this area are limited.

Elderly Patients

Elderly patients may exhibit reduced skin reactivity (smaller wheals) due to age-related changes in skin physiology and mast cell density. Healthcare providers may need to interpret results more conservatively in patients over 65.

Cashew extract is not for self-administration. It must be administered in a clinical setting equipped to handle anaphylaxis.

• Preparation: Ensure the patient has avoided antihistamines for at least 3 to 7 days prior to testing.
• Administration: The skin site should be cleaned with alcohol and allowed to dry. The extract should be stored at 2°C to 8°C (36°F to 46°F) and checked for clarity before use.
• Storage: Do not freeze. Discard if the solution becomes turbid or shows signs of precipitation.

In the context of diagnostic testing, a 'missed dose' is not applicable as it is a one-time procedure. For patients undergoing oral immunotherapy (OIT), a missed dose can be dangerous. If a dose of OIT is missed:

• 1 Dose Missed: Usually, the next dose is taken as scheduled.
• 2 Doses Missed: The dose may need to be reduced.
• 3+ Doses Missed: The patient may need to return to the clinic for a supervised escalation dose.

An 'overdose' of Cashew extract in a diagnostic setting occurs if too much extract is injected intradermally or if the concentration is too high for the patient's sensitivity level.

• Signs: Rapid development of a large wheal (>15mm), generalized itching, hives (urticaria), swelling of the throat (angioedema), wheezing, or a drop in blood pressure.
• Emergency Measures: Immediate administration of intramuscular epinephrine (0.3 mg for adults, 0.15 mg for children), followed by antihistamines, corticosteroids, and emergency room observation.

> Important: Follow your healthcare provider's dosing instructions. Do not adjust your dose without medical guidance.

The most frequent side effects associated with Cashew extracts occur at the site of administration. These are generally expected and indicate the test is working as intended in sensitized individuals.

• Localized Wheal: A raised, itchy bump at the test site. It usually appears within 15 minutes and subsides within a few hours. It may feel like a mosquito bite.
• Localized Erythema (Flare): Redness surrounding the wheal caused by vasodilation. This can range from a faint pink to a deep red circle.
• Pruritus (Itching): Intense itching at the site of the prick or injection. Patients should be advised not to scratch, as this can distort the results and cause skin irritation.

These reactions are more significant but usually remain localized to the limb where the test was performed.

• Large Local Reactions: A wheal or swelling that exceeds 10-15mm in diameter. This may be accompanied by warmth and tenderness at the site.
• Delayed Local Swelling: Some patients may experience a 'late-phase reaction' where the site swells again 4 to 8 hours after the initial test. This is typically managed with oral antihistamines.
• Mild Systemic Urticaria: A few hives appearing on parts of the body distant from the test site.

Rarely, the administration of Cashew extract can lead to more concerning symptoms that require monitoring.

• Lymphangitis: Inflammation of the lymph vessels leading away from the test site, appearing as red streaks.
• Vasovagal Reaction: Fainting or lightheadedness triggered by the needle prick or the sight of the procedure, rather than the extract itself.
• Persistent Granuloma: A small, firm bump at the injection site that may take weeks to resolve.

> Warning: Stop taking Cashew and call your doctor immediately if you experience any of these.

Systemic allergic reactions, including anaphylaxis, are the most serious risks associated with Cashew extracts. Because cashew is a potent allergen, even the small amount used in testing can be life-threatening for highly sensitive individuals.

• Anaphylaxis: A rapid, systemic allergic reaction involving two or more organ systems. Symptoms include a sudden drop in blood pressure, rapid pulse, and loss of consciousness.
• Angioedema: Severe swelling under the skin, particularly around the lips, eyes, tongue, or throat, which can obstruct the airway.
• Bronchospasm: Sudden constriction of the muscles in the walls of the bronchioles, leading to severe difficulty breathing, wheezing, and chest tightness.
• Generalized Urticaria: Widespread hives covering a large portion of the body, often accompanied by intense itching and swelling.
• Gastrointestinal Distress: Sudden onset of severe nausea, vomiting, or abdominal cramping following the administration of the extract.

There are no known long-term side effects from a one-time diagnostic use of Cashew extract. However, for patients undergoing long-term Oral Immunotherapy (OIT) with cashew components, potential long-term issues include:

• Eosinophilic Esophagitis (EoE): A chronic immune system disease where eosinophils (a type of white blood cell) build up in the lining of the esophagus, causing difficulty swallowing or food impaction. This is a known risk of long-term food allergen exposure in OIT.
• Chronic Sensitization: In rare cases, repeated exposure might theoretically worsen the underlying allergy, although the goal of therapy is the opposite.

While non-standardized food extracts do not always carry a specific 'Black Box' on the outer carton in the same way as high-risk pharmaceuticals, the FDA requires a General Warning for Allergenic Extracts regarding the risk of severe systemic reactions. The clinical literature emphasizes that Cashew extracts must only be used by physicians prepared to treat anaphylaxis. The warning states that these products can cause severe life-threatening systemic reactions, including anaphylactic shock and death, and should be administered only in facilities where emergency equipment and medications (like epinephrine) are immediately available.

Report any unusual symptoms to your healthcare provider.

Cashew extracts are potent biological agents. Their use is strictly limited to diagnostic or therapeutic protocols managed by board-certified allergists. Patients must be informed that while skin testing is generally safe, there is an inherent risk of a systemic reaction. Patients should remain in the clinic for at least 30 minutes following any exposure to the extract to ensure that any immediate hypersensitivity reactions can be treated promptly.

No FDA black box warnings for Cashew currently exist in the traditional sense; however, all allergenic extracts carry a prominent warning in their prescribing information regarding the risk of anaphylaxis. Healthcare providers must strictly adhere to the following: "This product should be used only by physicians experienced in the administration of allergenic extracts and the treatment of anaphylaxis. Patients should be observed for at least 30 minutes after administration."

Allergic Reactions / Anaphylaxis Risk

Patients with a history of severe, life-threatening reactions to cashews (anaphylaxis) are at the highest risk. In these patients, skin prick testing should be performed with extreme caution, often using higher dilutions (lower concentrations) than standard protocols. Intradermal testing is generally avoided in patients with a clear history of cashew-induced anaphylaxis due to the high risk of triggering a systemic event.

Asthma Status

Patients with unstable or poorly controlled asthma are at a significantly higher risk for severe or fatal reactions if a systemic allergic response occurs during testing. According to the AAAAI guidelines, a patient's asthma should be stable, and their FEV1 (Forced Expiratory Volume) should ideally be above 70-80% of their predicted value before undergoing allergen provocation or testing.

Beta-Blocker and ACE Inhibitor Use

Patients taking beta-blockers (e.g., metoprolol, propranolol) may be resistant to the effects of epinephrine if an emergency occurs. Similarly, ACE inhibitors (e.g., lisinopril) may exacerbate the severity of anaphylaxis and interfere with the body's compensatory mechanisms. These medications should be discussed thoroughly with the physician before testing.

During and after the administration of Cashew extract, the following must be monitored:

• Vital Signs: Pulse, blood pressure, and respiratory rate should be checked if the patient reports feeling unwell.
• Skin Site: The size of the wheal and flare must be measured accurately (in millimeters) to interpret the test.
• Subjective Symptoms: Patients should be asked about itching of the palms, throat tightness, or a 'sense of impending doom,' which are early signs of systemic reactions.

Diagnostic skin testing does not typically impair the ability to drive or operate machinery. However, if a systemic reaction occurs and the patient is treated with epinephrine or sedating antihistamines (like diphenhydramine), they should not drive or operate machinery until the effects of the medication have completely worn off and they have been cleared by a physician.

Alcohol consumption should be avoided on the day of testing. Alcohol can increase peripheral vasodilation, which may potentially increase the rate of allergen absorption or mask the symptoms of a mild systemic reaction.

If a patient experiences a systemic reaction during a testing or OIT protocol, the procedure must be discontinued immediately. Future testing should only be considered after a thorough risk-benefit analysis and potentially using a different diagnostic modality, such as in vitro IgE testing.

> Important: Discuss all your medical conditions with your healthcare provider before starting Cashew.

There are no drugs that are strictly contraindicated in the sense of a chemical incompatibility, but certain medications make the use of Cashew extract unsafe or uninterpretable:

• Antihistamines (H1 Blockers): Drugs like cetirizine, loratadine, and diphenhydramine must be stopped 3-7 days before testing. They block the histamine receptors in the skin, leading to a 'false negative' result where the patient is allergic but no wheal forms.
• Systemic Corticosteroids: High-dose, long-term steroids may suppress skin reactivity, although short-term or low-dose use is often acceptable. Talk to your doctor about your specific dose.

• Beta-Adrenergic Blockers: As mentioned, these drugs (e.g., atenolol, carvedilol) can block the life-saving effects of epinephrine. If a patient on a beta-blocker goes into anaphylaxis from Cashew extract, standard doses of epinephrine may fail, and they may require glucagon for resuscitation.
• Tricyclic Antidepressants (TCAs): Medications like amitriptyline or nortriptyline can have potent antihistamine properties that last for weeks, potentially interfering with diagnostic results for a prolonged period.

• H2 Antagonists: Drugs like famotidine or ranitidine (used for acid reflux) have a minor effect on skin testing. While not as significant as H1 blockers, they can still slightly reduce the size of the wheal.
• Topical Corticosteroids: If applied directly to the test site (e.g., the forearm), these will suppress the local inflammatory response and lead to inaccurate results.
• MAO Inhibitors: These can interact with the sympathetic nervous system and complicate the management of a systemic reaction if one occurs.

• Cross-Reactive Foods: Patients sensitive to cashew often show cross-reactivity with pistachios (both are in the Anacardiaceae family) and mangoes. Consuming these foods shortly before a skin test might theoretically prime the immune system and increase the risk of a larger reaction.
• High-Fat Meals: If cashew is being used as a lipid emulsion, high-fat meals can interfere with the clearance of the emulsion from the bloodstream.

• St. John's Wort: May affect the metabolism of certain secondary metabolites in the extract, though the clinical significance is low.
• Quercetin: This flavonoid has natural antihistamine properties and may slightly suppress the wheal and flare response if taken in high doses as a supplement.

• Skin Test Interference: The presence of Cashew extract in the skin only interferes with the interpretation of the skin test itself. It does not typically interfere with standard blood chemistry, CBC, or urinalysis.
• IgE Testing: Taking the skin test does not affect the results of a RAST or ImmunoCAP blood test, provided the blood is drawn before or significantly after the skin test.

For each major interaction, the mechanism involves either the pharmacological suppression of the allergic response (antihistamines/steroids) or the interference with emergency treatment (beta-blockers). The clinical consequence is either a diagnostic error (false negative) or increased medical risk. The management strategy is always to discontinue the interfering medication for an appropriate washout period before testing.

> Important: Tell your doctor about ALL medications, supplements, and herbal products you are taking.

Cashew extract must NEVER be used in the following circumstances:

• Recent Systemic Anaphylaxis: If a patient has experienced a systemic allergic reaction to any substance within the last 4 weeks, skin testing should be delayed. The body's mast cells may be 'exhausted' (depleted of histamine), leading to a false negative result, or the immune system may be in a hyper-irritable state, increasing the risk of another systemic reaction.
• Severe, Uncontrolled Asthma: As defined by frequent symptoms, nighttime awakenings, or low FEV1. The risk of a fatal respiratory event during a systemic reaction is too high.
• Dermatographism: A condition where any pressure or scratch on the skin causes a wheal. In these patients, the 'negative control' will be positive, making it impossible to interpret the cashew test.
• Generalized Skin Disease: Severe eczema or psoriasis at the site of testing prevents the clear visualization of a wheal and flare.

• Pregnancy: While not an absolute contraindication, diagnostic skin testing is usually deferred until after delivery to avoid any risk of anaphylaxis-induced fetal hypoxia.
• Beta-Blocker Therapy: Requires a careful risk-benefit analysis. If testing is essential, it may be performed in a hospital setting with glucagon available.
• Very Young Children (<6 months): Skin reactivity may be unreliable, and the clinical need for testing must be weighed against the difficulty of interpretation.

Patients with known severe allergies to the following should be approached with extreme caution due to high rates of cross-sensitivity with Cashew:

• Pistachio: Nearly 100% cross-reactivity is often observed.
• Mango: Specifically the skin of the fruit, which contains urushiol-like compounds similar to those in the cashew shell.
• Poison Ivy/Oak: These contain urushiols that are chemically related to the anacardic acids found in raw cashew extracts.

> Important: Your healthcare provider will evaluate your complete medical history before prescribing Cashew.

Cashew extract is categorized as FDA Pregnancy Category C. There are no adequate and well-controlled studies in pregnant women. The primary concern is not the direct effect of the extract on the fetus, but the risk of systemic anaphylaxis in the mother. Anaphylaxis can lead to maternal hypotension (low blood pressure) and uterine contractions, resulting in fetal hypoxia (lack of oxygen) or preterm labor. According to the AAAAI, skin testing for food allergens should generally be postponed until after pregnancy unless the information is critical for the immediate management of the patient.

It is not known whether the allergenic proteins in Cashew extract are excreted in human milk. However, since the amount used in diagnostic testing is microscopic, the risk to a nursing infant is considered negligible. For mothers undergoing Oral Immunotherapy (OIT), cashew proteins can be detected in breast milk, which may theoretically sensitize or cause a reaction in a highly allergic infant. Consult your doctor if you are breastfeeding and undergoing cashew-based therapies.

Cashew extracts are widely used in children, as tree nut allergies are a major concern in pediatric medicine.

• Safety: Testing is safe when performed by experts.
• Efficacy: Skin prick tests have a high negative predictive value (if the test is negative, the child is likely not allergic) but a lower positive predictive value (a positive test doesn't always mean a reaction will occur upon eating).
• Growth Effects: There are no known effects of diagnostic cashew extract on childhood growth or development.

Clinical studies of allergenic extracts generally do not include sufficient numbers of subjects aged 65 and over to determine whether they respond differently from younger subjects.

• Skin Reactivity: Older patients often have thinner skin and reduced mast cell reactivity, which can lead to smaller wheal sizes.
• Comorbidities: The presence of cardiovascular disease in the elderly increases the risk associated with a systemic reaction or the use of epinephrine.

In patients with chronic kidney disease (CKD), the clearance of systemic inflammatory mediators might be altered, but this does not change the standard protocol for skin testing. If cashew-derived lipid emulsions are used for total parenteral nutrition (TPN) in renal patients, lipid levels and renal markers must be monitored to prevent fat overload syndrome.

No specific dosage adjustments are required for skin testing in patients with hepatic impairment. For OIT, the liver's role in processing absorbed allergens and maintaining immune tolerance is complex, but current guidelines do not mandate dose changes based on Child-Pugh scores for diagnostic extracts.

> Important: Special populations require individualized medical assessment.

Cashew allergenic extract operates via the IgE-mediated Type I Hypersensitivity pathway. The primary allergens in the extract—Ana o 1, Ana o 2, and Ana o 3—are recognized by specific IgE antibodies bound to FceRI receptors on the surface of mast cells. Upon binding, these receptors cluster, leading to an influx of calcium ions and the subsequent degranulation of the mast cell. This releases pre-formed mediators like histamine and newly synthesized mediators like leukotrienes (LTC4, LTD4, LTE4). In its role as an Estrogen Receptor Agonist, cashew's anacardic acids mimic the phenolic structure of estradiol, allowing them to fit into the ligand-binding domain of estrogen receptors, albeit with a binding affinity several orders of magnitude lower than endogenous hormones.

The pharmacodynamic response to Cashew extract is rapid. In skin testing, the onset of the wheal and flare occurs within 5 to 10 minutes, peaking at 15 to 20 minutes. The duration of the visible reaction is typically 2 to 4 hours, though the underlying cellular infiltration (the late-phase reaction) can persist for up to 24 hours. The dose-response relationship is logarithmic; increasing the concentration of the extract leads to a proportional increase in the wheal diameter until a plateau is reached.

| Parameter | Value |

|---|---|

| Bioavailability | <1% (Percutaneous); ~10-20% (Oral/OIT) |

| Protein Binding | High (to specific IgE and albumin) |

| Half-life | 15-30 minutes (systemic proteins) |

| Tmax | 15-20 minutes (local reaction) |

| Metabolism | Proteolysis (enzymatic breakdown) |

| Excretion | Renal (metabolites) |

• Molecular Formula: N/A (Complex biological mixture)
• Major Components: Ana o 1 (7S vicilin), Ana o 2 (11S legumin), Ana o 3 (2S albumin).
• Solubility: Soluble in aqueous buffers and 50% glycerin solutions.
• Structure: The allergens are globular proteins with high thermal stability and resistance to proteolysis, which contributes to their high allergenicity.

Cashew is classified as a Non-Standardized Food Allergenic Extract [EPC]. It is grouped with other tree nut extracts (e.g., Walnut, Almond) and is distinct from 'Standardized' extracts (like Grass Pollen or Cat Dander), for which the FDA has established specific potency units (BAU/AU).