Lamb's Quarter Allergy Shots: Che a 1, Che a 2, Che a 3 — The Chenopodium Molecular Deep Dive
Lamb's quarter (Chenopodium album) allergy shots target the canonical Amaranthaceae allergen present on every inhabited continent — Che a 1 (Ole e 1-like, 77% sensitization rate), Che a 2 (profilin, 55%), and Che a 3 (polcalcin, 46%) per Barderas 2002 (Clin Exp Allergy).
Lamb's Quarter Allergy Immunotherapy: How It Works
Allergy immunotherapy is the only long-term treatment that re-trains the immune system to stop overreacting to lamb's quarter — rather than just masking symptoms with antihistamines or steroids. By gradually exposing the body to controlled doses of lamb's quarter allergen, immunotherapy shifts the underlying allergic response and produces relief that often outlasts treatment by 7–10 years.
There are two evidence-based forms of lamb's quarter immunotherapy used today, both built on the same desensitization principle but delivered very differently.
of sustained relief after a complete immunotherapy course — the only allergy treatment with proven long-term effect after stopping.
Allergy Shots (SCIT)
Weekly injections of lamb's quarter extract in a clinic, escalating over 3–6 months until a maintenance dose is reached. Continued monthly for 3–5 years. Longest clinical track record for lamb's quarter allergy.
- Strongest evidence base for severe and polysensitized patients
- Covered by most insurance plans
- Requires 50–100+ in-person clinic visits across the full course
Allergy Drops / Tablets (SLIT)
Daily drops or dissolvable tablets containing lamb's quarter extract, held under the tongue at home. Same desensitization principle, delivered without injections. WHO-recognized as an effective form of allergy immunotherapy since 2001.
- Taken at home — no weekly clinic trips, no needles
- Lower systemic reaction rate than allergy shots
- Curex offers prescription lamb's quarter immunotherapy drops with allergist oversight
The rest of this page goes deep on allergen-specific immunotherapy with shots — protocol, efficacy data, side effects, and cost. If you’d rather skip the clinic and treat lamb's quarter allergy with at-home drops, see how Curex sublingual immunotherapy compares below.
What is Lamb's Quarter?
The biology, taxonomy, and clinical fingerprint of Lamb's Quarter — the foundation of how SCIT targets it.
Chenopodium album (lamb's quarter / fat hen) pollen is 20-30 μm, wind-dispersed, and morphologically indistinguishable from Amaranthus under light microscopy — making combined chenopod-amaranth pollen counts standard practice.
- Scientific name
- Chenopodium album
- Family
- Amaranthaceae (includes former Chenopodiaceae per APG IV)Amaranth family (Chenopodioideae subfamily)
- Type
- Annual weed pollen
- Native to
- Eurasia; naturalized worldwide on every inhabited continent
- Allergen proteins
- Che a 1 (Ole e 1-like, major — 77% sensitization)Che a 2 (profilin, pan-allergen — 55% sensitization)Che a 3 (polcalcin, 2-EF-hand calcium-binding protein — 46% sensitization)
- Particle size
- 20-30 μm
- Avoidance difficulty
- Nearly impossible
How Lamb's Quarter Allergy Presents
Symptoms by body system — useful for distinguishing Lamb's Quarter sensitivity from overlapping allergies and infections.
Respiratory
- Seasonal rhinitis peaking August-October across all US regions
- Profuse watery nasal discharge and sneezing during peak lamb's quarter pollen dispersal
- Allergic asthma exacerbation in the late-summer weed season
- Post-nasal drip and chronic throat clearing through October
- Sinusitis and facial pressure overlapping with fall weed pollen
Ocular
- Intense allergic conjunctivitis during August-October
- Watery, itchy, red eyes on high pollen-count days
- Periorbital swelling with prolonged outdoor exposure
- Contact lens intolerance during peak season
Dermal
- Contact urticaria from handling lamb's quarter plants (widespread edible weed)
- Eczema flare in atopic patients during pollen season
- Pruritus of exposed skin on high-count outdoor days
Systemic
- Fatigue and cognitive impairment during prolonged August-October exposure
- Sleep disruption from nasal congestion and pruritus
- Polcalcin (Che a 3) cross-reactivity may contribute to OAS-type symptoms in some patients
- Profilin (Che a 2) may cause mild oral reactions with raw foods in sensitized individuals
One of the most common misconceptions I address in California allergy practice is whether patients who test positive for both lamb's quarter and olive are cross-reactive. Despite the Ole e 1 structural similarity to Che a 1, they do not cross-react clinically at a meaningful level. Barderas et al. confirmed this in 2002 — co-sensitization represents two independent sensitizations, not one shared one. Each allergen needs its own treatment consideration.
When & Where Lamb's Quarter Peaks
Allergen intensity by month and by state. Useful for timing SCIT start dates and travel planning.
12-Month Intensity
Peak: August-September across US; extends into November in mild climates (western Spain sensitization reaches 28-40% of pollen-allergic patients, Barderas 2002)· ~12-16 weeks; Anderegg 2021 (PNAS) documented a 20-day earlier pollen onset in North America 1990-2018
US Exposure Map
10 high-intensity statesWhat Lamb's Quarter Cross-Reacts With
Patients sensitized to one allergen often react to others sharing similar proteins. This map shows the documented molecular overlaps.
Lamb's quarter pollen shares Che a 2 (profilin) and Che a 3 (polcalcin) pan-allergens with the broader Amaranthaceae family, producing extensive extract-level cross-reactivity; the Che a 1 / Ole e 1 structural homology does NOT produce clinically meaningful cross-reactivity with olive pollen, and co-sensitization almost always represents true dual sensitization (Barderas 2002 Clin Exp Allergy; Villalba 2014 Curr Allergy Asthma Rep).
Same species (C. album) — 'common weed' in US clinical panels is the ambiguous label for this allergen
Sal k 4 profilin cross-reacts with Che a 2; Sal k 1 (pectin methylesterase) is structurally distinct from Che a 1
Is SCIT Right for Your Lamb's Quarter Allergy?
Answer 5 questions to determine whether lamb's quarter allergy shots match your fall allergy profile.
How severe are your lamb's quarter / fall weed symptoms (August-October)?
The Lamb's Quarter SCIT Protocol
Lamb's quarter SCIT uses non-standardized Chenopodium album extract (ImmunoCAP w10) and is frequently compounded with Russian thistle, kochia, and pigweed in a single fall-weed vial for polysensitized Plains and Southwest patients.
Incremental dose escalation, with the first dose and every dose change supervised live over Zoom by the prescribing physician and a prescribed epinephrine auto-injector confirmed on hand. Your allergist targets at least 12 weeks of build-up before the August lamb's quarter pollen peak to establish immunological tolerance before peak exposure. The Che a 1 protein is the key immunological target; build-up progressively shifts immune response from IgE-dominant to IgG4-dominant for this allergen.
Monthly injections sustain tolerance through multiple fall seasons; Curex delivers these as an at-home shot with dose changes supervised live over Zoom. Chenopodium album extract is commonly compounded with Russian thistle, kochia, and pigweed mix in Plains and Southwest fall-weed vials. Most patients notice meaningful reduction in rhinitis severity by the second fall pollen season on maintenance. A prescribed epinephrine auto-injector must be confirmed on hand throughout treatment.
After 3-5 years of maintenance therapy, many patients retain significant symptom reduction after stopping injections, consistent with the immunological reprogramming expected from successful immunotherapy. Your allergist will weigh symptom history, ongoing exposure levels, and treatment response.
Extract Concentration Ladder
You progress through each vial during build-up. Concentration increases ~10x per step.
What the Research Shows for Lamb's Quarter SCIT
Lamb's quarter SCIT lacks a species-specific RCT; efficacy is extrapolated from the Salsola SCIT RCT (closest Amaranthaceae family evidence) and weed-pollen SCIT practice parameters.
- Symptom score reduction — Salsola SCIT (closest Amaranthaceae RCT)42%Tabar AI et al. 2014, JACI 134:99-105, N=48 (Spanish multicenter RCT; Amaranthaceae family extrapolation)
- Weed-pollen SCIT medication score reduction50%Cox L et al. 2011, JACI 127:S1-55 (AAAAI Practice Parameter — general weed SCIT)
- Che a 1 sensitization rate in Chenopodium-allergic patients77%Barderas R et al. 2002, Clin Exp Allergy 32:1216-1222 (Che a 1/2/3 characterization study)
No published DBPC-RCT exists for lamb's quarter SCIT specifically. The Tabar 2014 JACI Salsola RCT provides the strongest within-family evidence for Amaranthaceae immunotherapy. The three-allergen Che a 1/2/3 panel is the best-characterized molecular profile in the Chenopodioideae subfamily, providing a strong foundation for allergen-specific testing and immunotherapy decisions.
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Lamb's Quarter SCIT Side Effects
Lamb's quarter SCIT follows the standard inhalant SCIT side-effect profile — local injection-site reactions are common, systemic reactions are uncommon, and anaphylaxis is rare but managed by the mandatory 30-minute at-home observation.
Local reactions
4 documentedSystemic reactions
4 documentedCurex delivers SCIT at home with safeguards built in: a USP <797> serum, a Zoom-supervised first dose and every dose change, a prescribed epinephrine auto-injector confirmed on hand, and gradual allergist-overseen escalation — so systemic reactions are anticipated and managed without a weekly clinic visit.
SCIT vs Alternatives for Lamb's Quarter
Chenopodium-sensitized patients have four main options, with SCIT providing the only long-term disease modification for lamb's quarter allergy.
| Criterion | At-Home SCIT (Curex)Best | SLIT drops/tablets | Avoidance | Medications |
|---|---|---|---|---|
| Effectiveness | High — family RCT support | Moderate — European data | Minimal — ubiquitous plant | Good symptom control |
| 5-yr cost | $3,500-$15,000 | $1,500-$5,000 | Low | $500-$2,000/yr |
| Duration | 3-5 years | 3-5 years | Ongoing | Ongoing daily use |
| Convenience | At-home self-injection; weekly then monthly | Daily home dosing | Very difficult Aug-Oct | Daily pills/sprays |
| Safety | Zoom-supervised dosing + prescribed epi | Lower systemic risk | Safe | Safe long-term |
| Lasting effect | Yes — post-treatment | Emerging evidence | No | No — symptoms return off meds |
At-Home SCIT (Curex)Best
SLIT drops/tablets
Avoidance
Medications
For patients with confirmed Che a 1 sensitization and multi-year fall symptoms, SCIT provides disease-modifying benefit that medications alone cannot achieve. Curex now delivers that SCIT as an at-home allergy shot at $129/month: a lamb's quarter (Chenopodium album) serum compounded under USP <797>, with the first dose and every dose change supervised live over Zoom, a prescribed epinephrine auto-injector confirmed on hand, and allergist-overseen escalation — so eligible patients get the disease-modifying benefit without weekly clinic visits during build-up.
What Lamb's Quarter SCIT Actually Costs
Lamb's quarter SCIT (Chenopodium album, CPT 95115/95117/95165) is typically covered by major US insurers under standard allergy benefits when prescribed by a board-certified allergist. Prior authorization is commonly required. Actual out-of-pocket cost depends on your plan's deductible and co-insurance; request a benefits verification before starting. Curex at-home IgE testing identifies specific lamb's quarter sensitization before allergist consultations, eliminating the need for an initial skin-test visit.
Cost range varies by deductible, co-insurance, and clinic.
Verify these codes with your insurer to confirm coverage.
Flat monthly subscription — includes consult, prescription, and at-home dosing for sublingual immunotherapy.
See if you qualifyStop guessing about your lamb's quarter allergy. Get a plan.
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Lamb's Quarter SCIT — Frequently Asked
Quick answers to the questions patients ask most before starting treatment.
Despite sharing structural homology between Che a 1 (lamb's quarter) and Ole e 1 (olive) — both are Ole e 1-like proteins — their actual immunological cross-reactivity is low and clinically irrelevant per Barderas et al. 2002 (Clin Exp Allergy) and Villalba et al. 2014 (Curr Allergy Asthma Rep). This is an important distinction for California patients, where both olive trees and lamb's quarter are abundant. If you test positive for both, you almost certainly have two independent sensitizations rather than one cross-reactive one — and you likely need immunotherapy coverage for both allergens separately. A board-certified allergist can confirm via specific IgE testing whether your sensitization levels are consistent with true dual sensitization.
This content is for informational purposes only and does not constitute medical advice, diagnosis, or treatment. Always consult a qualified healthcare provider with questions about a medical condition. Content reviewed by board-certified allergists at Curex.