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Dosage for Atriplex Canescens Pollen is highly individualized and must be determined by an allergist or immunologist based on the patient's sensitivity level and clinical response. There is no "standard" dose due to the non-standardized nature of the extract.

Diagnostic Dosing

• Prick/Punch Testing: Usually performed using a 1:10 or 1:20 w/v concentration. A single drop is applied to the skin, and the skin is pricked through the drop.
• Intradermal Testing: If prick tests are negative, a more sensitive intradermal test may be performed using a much more dilute solution, typically 0.02 mL of a 1:1000 or 1:500 w/v concentration.

Therapeutic Dosing (Immunotherapy)

Immunotherapy consists of two distinct phases:

1. 1Build-up (Escalation) Phase: This phase involves weekly or bi-weekly injections. The starting dose is usually very low (e.g., 0.05 mL of a 1:100,000 or 1:10,000 w/v dilution). The dose is gradually increased every 3 to 7 days until the maintenance dose is reached. This typically takes 3 to 6 months.
2. 2Maintenance Phase: Once the "top dose" or maintenance dose is reached (often 0.5 mL of a 1:100 or 1:20 w/v concentration), the interval between injections is increased to every 2 to 4 weeks. Maintenance therapy usually lasts for 3 to 5 years.

Atriplex Canescens Pollen is generally considered safe for use in children, typically starting at age 5. Dosing protocols for children are generally similar to adult protocols, though the starting dose may be even more conservative depending on the child's history of asthma or sensitivity. Children should be closely monitored for systemic reactions, as they may have more difficulty communicating early symptoms of anaphylaxis.

Renal Impairment

No specific dosage adjustments are required for patients with renal impairment, as the extract is not cleared in a manner that would lead to accumulation of toxic metabolites. However, the patient's overall health and ability to tolerate a systemic reaction should be considered.

Hepatic Impairment

No dosage adjustments are necessary for hepatic impairment.

Elderly Patients

Caution is advised in elderly patients (over 65). While the dose remains the same, these patients are more likely to have underlying cardiovascular disease, which increases the risk and severity of a systemic reaction if anaphylaxis occurs. Furthermore, they may be taking medications like beta-blockers that complicate the treatment of anaphylaxis.

Atriplex Canescens Pollen is administered exclusively by subcutaneous injection, usually in the posterior aspect of the upper arm.

• Preparation: The vial should be inspected for particulate matter or discoloration before use. It should be at room temperature or slightly chilled.
• Administration: The injection must be subcutaneous, not intramuscular or intravenous. The clinician must aspirate before injecting to ensure a blood vessel has not been entered.
• Observation: Patients MUST remain in the medical office for at least 30 minutes following every injection. This is the period of highest risk for life-threatening anaphylaxis.
• Storage: Vials must be stored in a refrigerator at 2°C to 8°C (36°F to 46°F). Potency is lost rapidly if the extract is left at room temperature or frozen.

If a dose is missed during the build-up phase, the next dose may need to be reduced to ensure safety.

• 1 week late: Usually, the same dose can be given.
• 2-4 weeks late: The dose may be reduced to the previous level or lower.
• Over 4 weeks late: The entire dilution series may need to be restarted.

An "overdose" in the context of allergenic extracts refers to an injection of a dose higher than the patient's current tolerance level. This most commonly occurs due to a clerical error or a failure to adjust the dose during a high-pollen season.

• Signs: Rapid onset of hives, swelling (angioedema), wheezing, shortness of breath, drop in blood pressure, or loss of consciousness.
• Emergency Measures: Immediate administration of epinephrine (1:1000) intramuscularly, followed by antihistamines, corticosteroids, and oxygen. Emergency medical services (911) should be summoned if a systemic reaction occurs.

> Important: Follow your healthcare provider's dosing instructions. Do not adjust your dose without medical guidance. Always inform your doctor if you have had a reaction to a previous dose.

Local reactions are the most frequent side effect of Atriplex Canescens Pollen injections. These occur in nearly all patients at some point during therapy.

• Local Swelling and Redness: A "lump" or area of redness at the injection site. This typically appears within minutes and may peak several hours later.
• Pruritus (Itching): Intense itching at the site of the injection.
• Induration: A hardening of the skin at the site, which may feel warm to the touch. These reactions are generally considered "normal" unless they exceed the size of a half-dollar (approx. 3 cm), in which case the next dose may need to be adjusted.

• Large Local Reactions: Swelling that extends beyond the immediate injection site, sometimes involving the entire upper arm. These may last for 24 to 48 hours.
• Fatigue: Some patients report feeling unusually tired for a few hours after an injection.
• Mild Nasal Congestion: A slight increase in hay fever symptoms shortly after the injection as the body processes the allergen.

• Generalized Urticaria (Hives): Itching and hives appearing on parts of the body far from the injection site.
• Angioedema: Swelling of the lips, tongue, or eyelids.
• Gastrointestinal Distress: Nausea, abdominal cramping, or diarrhea occurring as part of a systemic allergic response.

> Warning: Stop taking Atriplex Canescens Pollen and call your doctor immediately if you experience any of these symptoms of anaphylaxis.

• Respiratory Distress: Wheezing, chest tightness, or a persistent cough. This indicates the allergen is affecting the lower airways.
• Laryngeal Edema: A feeling of a "lump in the throat," hoarseness, or difficulty swallowing, indicating swelling of the airway.
• Hypotension (Low Blood Pressure): Feeling faint, dizzy, or passing out. This is a sign of anaphylactic shock.
• Cyanosis: A bluish tint to the lips or fingernails, indicating a lack of oxygen.
• Uterine Contractions: In pregnant women, systemic reactions can trigger uterine activity.

There are no known long-term adverse effects associated with the proper use of Atriplex Canescens Pollen. Allergen immunotherapy has been used for over a century, and studies have not shown an increased risk of autoimmune disease, malignancy, or chronic organ damage. The primary "long-term" effect is the desired one: a significant reduction in allergic sensitivity that often persists for years after the treatment is discontinued.

Atriplex Canescens Pollen, like all allergenic extracts, carries a stringent FDA-mandated warning regarding the risk of severe systemic reactions.

WARNING: RISK OF ANAPHYLAXIS

• Allergenic extracts can cause severe life-threatening systemic reactions, including anaphylaxis and death.
• This product should only be administered in a healthcare setting by personnel trained in the emergency treatment of anaphylaxis.
• Patients must be observed for at least 30 minutes after each injection.
• Patients with unstable or severe asthma are at increased risk for fatal reactions.
• Patients taking beta-blockers may be resistant to the effects of epinephrine used to treat anaphylaxis.

Report any unusual symptoms to your healthcare provider. Even if a reaction seems mild, it may be a precursor to a more severe reaction at the next dose.

Atriplex Canescens Pollen is a potent biological product. Its safety depends entirely on correct administration and patient monitoring. It is not a medication that patients can administer to themselves at home. Every injection carries a non-zero risk of a systemic allergic reaction, regardless of how long the patient has been on the therapy.

As noted in the side effects section, the FDA requires a Black Box Warning for Atriplex Canescens Pollen due to the potential for sudden, life-threatening anaphylaxis. This warning emphasizes that the extract is only for use by physicians experienced in respiratory diseases and allergy, and that the facility must have the equipment and medications (including oxygen, IV fluids, and intubation equipment) necessary to manage a full cardiac or respiratory arrest.

Allergic Reactions / Anaphylaxis Risk

The primary risk is an IgE-mediated systemic reaction. Factors that increase this risk include:

• High Pollen Season: During the time of year when Fourwing Saltbush is naturally pollinating, the patient's "allergic load" is higher, making them more sensitive to the injections.
• Exercise: Strenuous exercise shortly after an injection increases blood flow and can cause the allergen to be absorbed too quickly, triggering a reaction.
• Infection/Illness: Patients who are currently ill with a fever or respiratory infection should have their injection deferred.

Asthma Status

Patients with asthma must have their condition well-controlled (e.g., FEV1 > 80% of predicted) before receiving an injection. Uncontrolled asthma is the single greatest risk factor for a fatal reaction to immunotherapy.

Cardiovascular Risks

While the extract itself does not damage the heart, the physiological stress of anaphylaxis (hypoxia and hypotension) can trigger a myocardial infarction (heart attack) or arrhythmia in patients with pre-existing heart disease.

• Pre-Injection Assessment: Before every dose, the clinician must ask the patient about any reactions to the previous dose and assess their current asthma symptoms.
• Peak Flow Monitoring: For asthmatic patients, a peak flow meter may be used to ensure lung function is stable before the injection.
• 30-Minute Wait: This is a mandatory monitoring period. Most fatal reactions occur within 20 minutes of injection.

There is no direct contraindication for driving after an injection, provided the patient has completed their 30-minute wait and feels well. However, if a patient experiences even a mild systemic reaction (like hives or lightheadedness), they should not drive until cleared by a physician.

Alcohol consumption should be avoided on the day of the injection. Alcohol can cause vasodilation, which may increase the rate of allergen absorption and potentially mask the early symptoms of a reaction.

If a patient repeatedly experiences systemic reactions despite dose adjustments, the therapy should be discontinued. Immunotherapy is also typically stopped if the patient fails to show clinical improvement after 12 to 24 months of maintenance-level dosing.

> Important: Discuss all your medical conditions with your healthcare provider before starting Atriplex Canescens Pollen.

There are no absolute drug-drug contraindications that prevent the use of Atriplex Canescens Pollen, but certain combinations significantly increase the risk of a poor outcome.

• Non-Selective Beta-Blockers: (e.g., Propranolol). These drugs are contraindicated in many immunotherapy protocols because they block the receptors that epinephrine acts upon. If a patient on a beta-blocker has anaphylaxis, the standard treatment (epinephrine) may fail, leading to a fatal outcome.

• Selective Beta-Blockers: (e.g., Atenolol, Metoprolol). While less dangerous than non-selective ones, they still pose a significant risk during anaphylaxis treatment.
• ACE Inhibitors: (e.g., Lisinopril). These medications can interfere with the body's natural ability to compensate for a drop in blood pressure and may increase the risk of more severe or frequent systemic reactions to immunotherapy.
• MAO Inhibitors: (e.g., Phenelzine). These can potentiate the effects of epinephrine, leading to a hypertensive crisis if epinephrine must be administered for a reaction.

• Antihistamines: (e.g., Loratadine, Cetirizine). While often used to treat allergies, taking an antihistamine right before an injection can mask the early "warning signs" of a systemic reaction (like itching or mild hives), potentially allowing a more severe reaction to develop unnoticed.
• Tricyclic Antidepressants: Similar to MAOIs, these can affect the body's response to epinephrine.

There are no direct food interactions with Atriplex Canescens Pollen. However, patients with "Oral Allergy Syndrome" (cross-reactivity between pollens and certain raw fruits/vegetables) should be aware that their sensitivity to those foods might fluctuate during the build-up phase of immunotherapy.

There is little clinical data on herbal interactions. However, supplements that have mild anticoagulant effects (like high-dose Vitamin E or Ginkgo Biloba) might theoretically increase the risk of bruising at the injection site.

• Skin Tests: Atriplex Canescens Pollen will interfere with subsequent skin testing for other allergens if the tests are performed too close to the injection site or during the peak of an immunotherapy-induced immune shift.
• Specific IgE (ImmunoCAP): During the first few months of therapy, a patient's serum IgE levels to Fourwing Saltbush may actually increase before they eventually decrease. This is a normal part of the immune response and does not necessarily indicate a failure of treatment.

For each major interaction, the management strategy is usually to either switch the offending medication (e.g., move from a beta-blocker to a calcium channel blocker for blood pressure) or to proceed with extreme caution under the guidance of both the allergist and the prescribing specialist.

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

1. 1Severe, Uncontrolled Asthma: Patients with an FEV1 persistently below 70% of predicted or those who have had a recent life-threatening asthma exacerbation should not receive Atriplex Canescens Pollen. The risk of a fatal bronchospasm during a systemic reaction is too high.
2. 2Recent Myocardial Infarction or Unstable Angina: The physiological stress of a potential allergic reaction could trigger a secondary cardiac event.
3. 3History of Severe Anaphylaxis to this Specific Extract: If a patient has previously had a near-fatal reaction to Atriplex Canescens Pollen despite proper dosing, the risks of continuing outweigh the benefits.

1. 1Beta-Blocker Therapy: As discussed, this makes treating a reaction difficult. This is a relative contraindication; the physician must weigh the necessity of the beta-blocker against the necessity of the allergy treatment.
2. 2Pregnancy (Initiation): Immunotherapy should never be started during pregnancy due to the risk of anaphylaxis-induced fetal hypoxia. However, if a woman is already on a stable maintenance dose and becomes pregnant, the treatment is often continued.
3. 3Autoimmune Diseases: Patients with active, systemic autoimmune disorders (like SLE or Polyarteritis Nodosa) are often excluded from immunotherapy because the immune stimulation could theoretically worsen their underlying condition.
4. 4Severe Psychological Disorders: The patient must be able to understand the risks and comply with the 30-minute waiting period.

Atriplex Canescens is part of the Amaranthaceae family (formerly Chenopodiaceae). Patients sensitive to Fourwing Saltbush may show cross-reactivity with:

• Russian Thistle (Salsola tragus)
• Lamb’s Quarters (Chenopodium album)
• Burning Bush/Kochia (Kochia scoparia)

> Important: Your healthcare provider will evaluate your complete medical history before prescribing Atriplex Canescens Pollen.

Atriplex Canescens Pollen is classified as Pregnancy Category C. There have been no adequate and well-controlled studies in pregnant women.

• Risk Summary: The primary risk to the fetus is maternal anaphylaxis, which can lead to placental hypoperfusion, fetal hypoxia, and miscarriage or preterm labor.
• Clinical Management: Initiation of immunotherapy is contraindicated during pregnancy. However, maintenance therapy is generally considered safe to continue if the patient is tolerating it well, as the risk of a reaction is much lower during the maintenance phase than during the build-up phase. Doses should not be increased during pregnancy.

It is not known whether the allergenic components of Atriplex Canescens Pollen are excreted in human milk. However, because these are large proteins that are degraded in the mother's system, it is highly unlikely that they would be present in breast milk in a form that would affect the nursing infant. Breastfeeding is not a contraindication for receiving allergy injections.

Allergen immunotherapy is widely used and effective in the pediatric population.

• Age Limit: Generally not recommended for children under the age of 5, primarily because younger children may be unable to cooperate with the procedure or articulate the early symptoms of a systemic reaction.
• Benefits: Early intervention with AIT in children has been shown in some studies to reduce the risk of developing asthma later in life (the "allergic march").

Patients over age 65 can receive Atriplex Canescens Pollen, but the risk-benefit ratio must be carefully assessed.

• Cardiovascular Reserve: Older adults have less physiological reserve to survive a severe anaphylactic event.
• Polypharmacy: Increased likelihood of taking beta-blockers or ACE inhibitors.
• Efficacy: Some studies suggest that the immune system's plasticity decreases with age, potentially making immunotherapy slightly less effective in the elderly compared to younger patients.

No dosage adjustments are needed. The proteins are metabolized by proteases and the resulting amino acids are handled by normal metabolic pathways. There is no evidence of increased toxicity in patients with chronic kidney disease.

No dosage adjustments are required. The liver is not the primary site of clearance for these biological proteins.

> Important: Special populations require individualized medical assessment and a cautious approach to dosing.

Atriplex Canescens Pollen acts as an immunomodulator. In the diagnostic phase, it acts as an antigen that cross-links IgE on mast cells. In the therapeutic phase, it induces a state of desensitization. The molecular mechanism involves the induction of T-regulatory (Treg) cells that secrete IL-10 and TGF-beta. These cytokines suppress the Th2 response and induce B-cells to switch production from IgE to IgG4. IgG4 acts as a "blocking antibody," preventing the allergen from reaching the mast-cell-bound IgE.

• Onset of Action: For skin testing, the onset is 15–20 minutes. For immunotherapy, clinical improvement typically takes 6 to 12 months of consistent treatment.
• Duration of Effect: The diagnostic wheal-and-flare resolves within hours. The therapeutic effect of a completed 3-5 year course of AIT can last for many years, sometimes providing a permanent reduction in symptoms.
• Dose-Response: There is a clear dose-response relationship in AIT; higher maintenance doses (within the patient's tolerance) are generally more effective than low-dose "homeopathic" concentrations.

| Parameter | Value |

|---|---|

| Bioavailability | N/A (Subcutaneous injection) |

| Protein Binding | N/A (Biological proteins) |

| Half-life | Variable (Hours for proteins; years for immune memory) |

| Tmax | 30-60 minutes (Systemic absorption of proteins) |

| Metabolism | Proteolysis (by tissue and plasma proteases) |

| Excretion | Renal (as amino acids/small peptides) |

• Composition: A complex aqueous extract containing proteins, glycoproteins, lipids, and carbohydrates. The major allergens are typically proteins in the 10-70 kDa range.
• Solubility: Highly soluble in aqueous buffered solutions or 50% glycerin.
• Source: Collected from the male flowers of Atriplex canescens (Fourwing Saltbush).

Atriplex Canescens Pollen is classified as a Non-Standardized Pollen Allergenic Extract. It is part of the broader category of Allergenic Extracts used for immunotherapy and diagnosis, which also includes standardized extracts (e.g., Cat Hair, Grasses) and other non-standardized extracts (e.g., Molds, Trees).