Common Weed Allergy Shots: Decoding the Most Ambiguous Label on US Allergy Panels
In US clinical allergy testing, 'common weed' almost always means Chenopodium album (lamb's quarter) — the globally distributed goosefoot tested under ImmunoCAP code w10. Patients who see 'common weed' on their lab results are reading their Chenopodium album sensitization, driven by the Che a 1 major allergen (77% sensitization rate, Barderas 2002).
About Curex’s SCIT program
Curex’s at-home allergy shots (SCIT) are coming soon and focus on the most common environmental allergens:
- • Pollens — tree, grass, weed & ragweed
- • Pet dander — cat & dog
- • Dust mites
- • Molds — Alternaria & mold mix
Common Weedis covered here for general education and may not be part of Curex’s current treatment set. Join the waitlist and our care team will help confirm your options.
Common Weed Allergy Immunotherapy: How It Works
Allergy immunotherapy is the only long-term treatment that re-trains the immune system to stop overreacting to common weed — rather than just masking symptoms with antihistamines or steroids. By gradually exposing the body to controlled doses of common weed 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 common weed 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 common weed 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 common weed 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
- Or at home with no clinic visits— Curex’s Virtual Shot Room model delivers the same SCIT program with live video supervision by trained Curex clinical staff for the first injection from each new vial or concentration and restarts after gaps or reactions.
Allergy Drops / Tablets (SLIT)
Daily drops or dissolvable tablets containing common weed 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 common weed 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 common weed allergy with at-home drops, see how Curex sublingual immunotherapy compares below.
What is Common Weed?
The biology, taxonomy, and clinical fingerprint of Common Weed — the foundation of how SCIT targets it.
Chenopodium album (common weed / lamb's quarter) is present in all 50 US states. Its pollen is morphologically indistinguishable from Amaranthus under light microscopy, so pollen counts are reported jointly as 'chenopod-amaranth.'
- Scientific name
- Chenopodium album
- Family
- Amaranthaceae (includes former Chenopodiaceae per APG IV)Amaranth family
- Type
- Annual weed pollen
- Native to
- Eurasia; now present on every inhabited continent including all 50 US states
- Allergen proteins
- Che a 1 (Ole e 1-like, major — 77% sensitization)Che a 2 (profilin, pan-allergen — 55% sensitization)Che a 3 (polcalcin — 46% sensitization)
- Particle size
- 20-30 μm
- Avoidance difficulty
- Nearly impossible
How Common Weed Allergy Presents
Symptoms by body system — useful for distinguishing Common Weed sensitivity from overlapping allergies and infections.
Respiratory
- Seasonal rhinitis with nasal congestion and sneezing, peaking August-October
- Profuse watery nasal discharge during high chenopod-amaranth pollen count days
- Allergic asthma exacerbation during late-summer weed pollen peak
- Post-nasal drip and chronic throat clearing throughout fall weed season
- Sinusitis and facial pressure overlapping with peak pollen weeks
Ocular
- Allergic conjunctivitis with itching and tearing during August-October
- Red, watery eyes worsened by outdoor exposure
- Periorbital swelling on high-count days
- Contact lens intolerance during peak season
Dermal
- Contact urticaria from handling Chenopodium album plants
- Eczema flare in atopic patients during high-pollen-count weeks
- Pruritus of skin with prolonged outdoor exposure
Systemic
- Fatigue and reduced productivity during prolonged August-October season
- Sleep disruption from nasal congestion
- Profilin (Che a 2) cross-reactivity may produce mild OAS reactions with some raw foods
- Polcalcin (Che a 3) cross-reactivity with other pollens in susceptible patients
When a patient brings me a lab result saying 'common weed positive,' I immediately clarify: that is Chenopodium album — lamb's quarter. The US allergy testing system uses this ambiguous term on panels because it was the historically common name, but the extract behind the test is always C. album, ImmunoCAP w10. The treatment is the same as for lamb's quarter — same allergen, same protocol, same evidence base.
When & Where Common Weed 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 through October in mild climates· ~12-16 weeks of exposure; pollen season extended ~20 days earlier since 1990 per Anderegg 2021 PNAS
US Exposure Map
10 high-intensity statesExposure intensity by state (text version)
- ME:
- Low
- VT:
- Low
- NH:
- Low
- WA:
- Low
- MT:
- Moderate
- ND:
- Moderate
- MN:
- Moderate
- WI:
- Low
- MI:
- Low
- NY:
- Low
- MA:
- Low
- OR:
- Moderate
- ID:
- Moderate
- WY:
- Moderate
- SD:
- Moderate
- IA:
- Moderate
- IL:
- Moderate
- IN:
- Moderate
- OH:
- Moderate
- PA:
- Low
- NJ:
- Low
- CT:
- Low
- RI:
- Low
- CA:
- High
- NV:
- High
- UT:
- High
- CO:
- High
- NE:
- High
- MO:
- Moderate
- KY:
- Low
- WV:
- Low
- VA:
- Low
- MD:
- Low
- DE:
- Low
- AZ:
- High
- NM:
- High
- KS:
- High
- AR:
- Moderate
- TN:
- Low
- NC:
- Low
- SC:
- Low
- OK:
- High
- LA:
- Moderate
- MS:
- Low
- AL:
- Low
- GA:
- Low
- TX:
- High
- FL:
- Low
- AK:
- Low
- HI:
- Low
What Common Weed Cross-Reacts With
Patients sensitized to one allergen often react to others sharing similar proteins. This map shows the documented molecular overlaps.
Common weed (Chenopodium album) shares Che a 2 (profilin) and Che a 3 (polcalcin) with other Amaranthaceae members, producing extensive extract-level cross-reactivity within the family; Che a 1 (Ole e 1-like) has structural homology with olive Ole e 1 but cross-reactivity is low and clinically irrelevant — co-sensitization with olive represents true dual sensitization (Barderas 2002).
Same species (C. album) — lamb's quarter page covers the molecular deep dive on Che a 1/2/3
Is SCIT Right for Your Common Weed Allergy?
Answer 5 questions to see whether the allergen behind your 'common weed' positive result warrants allergy shots.
How severe are your fall weed symptoms (August-October)?
The Common Weed SCIT Protocol
Common weed SCIT uses Chenopodium album extract (the same extract as lamb's quarter, ImmunoCAP w10) in a non-standardized formulation, frequently compounded with Russian thistle, kochia, and pigweed in a fall-weed vial for polysensitized Plains and Southwest patients.
Incremental dose escalation from dilute starting concentration, with the first injection from each new vial or concentration supervised live in the Virtual Shot Room by trained Curex clinical staff, a prescribed epinephrine auto-injector confirmed on hand, and a brief self-observation afterward. Because common weed = Chenopodium album = lamb's quarter, the build-up protocol is identical to lamb's quarter SCIT. Allergists aim to complete build-up at least 12 weeks before August to establish tolerance before peak pollen season.
Maintenance injections sustain tolerance. Common weed extract is commonly compounded with Russian thistle, kochia, and pigweed for fall-season polysensitized patients across the Plains and Southwest. Epinephrine auto-injector must be available throughout treatment.
After 3-5 years of maintenance, many patients retain significant symptom reduction after stopping injections. Decision to discontinue is made jointly with the allergist based on symptom trajectory and ongoing exposure levels.
Extract Concentration Ladder
You progress through each vial during build-up. Concentration increases ~10x per step.
What the Research Shows for Common Weed SCIT
Common weed (Chenopodium album) SCIT efficacy is extrapolated from the Salsola SCIT RCT (Tabar 2014 JACI — closest Amaranthaceae family evidence) and weed-pollen SCIT practice parameters; no C. album-specific RCT exists.
- Symptom score reduction — Salsola SCIT (closest Amaranthaceae family evidence)42%Tabar AI et al. 2014, JACI 134:99-105, N=48 (Amaranthaceae family extrapolation)
- Weed-pollen SCIT medication score reduction50%Cox L et al. 2011, JACI 127:S1-55 (AAAAI Practice Parameter)
- Che a 1 sensitization rate in Chenopodium-allergic patients77%Barderas R et al. 2002, Clin Exp Allergy 32:1216-1222 (C. album allergen characterization)
No direct RCT exists for Chenopodium album SCIT. Efficacy is extrapolated from the Tabar 2014 JACI Salsola SCIT trial and general weed-pollen immunotherapy data. The well-characterized Che a 1/2/3 allergen panel provides a solid molecular foundation for treatment targeting. Patients should discuss the evidence gap honestly with their allergist.
Ready to skip the surprise bills?
At-home allergy shots (SCIT) are designed by board-certified allergists. See the listed SCIT plan rate in our pricing record and request a quote for eligibility, initiation and total care costs.
- MD-ledBoard-certified allergists
- QuoteTotal care estimate
- 50K+Patients treated
- HSA/FSAEligible
Common Weed SCIT Side Effects
Common weed SCIT (Chenopodium album extract) follows the standard inhalant SCIT side-effect profile — local reactions are common, systemic reactions are uncommon. With Curex's at-home program, a prescribed epinephrine auto-injector is confirmed on hand and the first injection from each new vial or concentration is supervised live in the Virtual Shot Room by trained Curex clinical staff so any systemic event is managed promptly.
Local reactions
4 documented| Reaction | Rate | Severity |
|---|---|---|
Injection-site wheal and flare Resolves within 30-60 minutes; ice and antihistamine reduce discomfort | Rate 30-50% | Mild |
Injection-site itching | Rate 25-40% | Mild |
Large local reaction (>5 cm) Dose adjusted at next visit; resolves within 24 hours | Rate 5-10% | Moderate |
Delayed local swelling | Rate 2-5% | Mild |
Systemic reactions
4 documented| Reaction | Rate | Severity |
|---|---|---|
Nasal or conjunctival flare | Rate 1-3% | Mild |
Urticaria | Rate 0.5-1% | Moderate |
Mild bronchospasm Asthma must be well-controlled before each injection | Rate 0.1-0.5% | Moderate |
Anaphylaxis Managed with a prescribed epinephrine auto-injector confirmed on hand; reactions typically begin within ~30 minutes, so Curex supervises the first injection from each new vial or concentration live in the Virtual Shot Room | Rate <0.1% per injection | Severe |
Traditionally SCIT was given only in a medical setting, but for eligible patients Curex enables safe at-home self-administration: a personalized serum sterile-compounded to USP <797> and lot-tested, a prescribed epinephrine auto-injector confirmed on hand before the first injection, and the first injection from each new vial or concentration supervised live in the Virtual Shot Room by trained Curex clinical staff. Systemic reactions almost always begin within the first 30 minutes, so a brief post-injection self-observation is advised. A large safety study of self-administered allergen immunotherapy (Schaffer et al., 2015) found that across 23,614 patients giving 2,021,600 injections the systemic reaction rate was just 0.16% per patient with no fatalities — lower than the 3%–14% typically seen with office-based shots.
SCIT vs Alternatives for Common Weed
Patients with confirmed Chenopodium album (common weed) sensitization have four main options, with SCIT offering the only disease-modifying strategy for fall weed allergy.
| Criterion | At-Home SCIT (Curex)Best | SLIT | Avoidance | Medications |
|---|---|---|---|---|
| Effectiveness | High — family-level evidence | Moderate — European weed 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 |
| Convenience | Weekly at home during build-up, then monthly — no clinic visits | Daily home dosing | Very difficult Aug-Oct | Daily pills/sprays |
| Safety | Prescribed epi on hand; Virtual Shot Room–supervised first/changed doses (~30-min onset) | Lower systemic risk | Safe | Safe long-term |
| Lasting effect | Yes — post-treatment | Emerging evidence | No | No — returns off meds |
At-Home SCIT (Curex)Best
SLIT
Avoidance
Medications
For patients who have confirmed that 'common weed' = Chenopodium album and have multi-year inadequate symptom control, SCIT is the disease-modifying option. Curex delivers C. album immunotherapy as a weekly shot you give yourself at home with pricing confirmed in a current program quote — a personalized serum sterile-compounded to USP <797>, the first injection from each new vial or concentration supervised live in the Virtual Shot Room by trained Curex clinical staff, with a prescribed epinephrine auto-injector confirmed on hand — removing the weekly clinic visit burden of the traditional 3-6 month build-up phase.
What Common Weed SCIT Actually Costs
Common weed (Chenopodium album) SCIT is covered under standard allergy benefit codes by most major US insurers when prescribed by a board-certified allergist. Prior authorization is routinely required. Out-of-pocket cost depends on your plan's deductible and co-insurance; contact your allergist's billing team for a benefits verification. Curex at-home IgE testing identifies specific common weed 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.
See the listed Environmental Allergy Shots Plan rate, commercial terms dated 2026-10-12; consultations are included without copay. Confirm availability, eligibility, other included services, testing, any in-person care, insurance responsibility and billing cadence in your written quote before enrolling.
Join the waitlistStop guessing about your common weed allergy. Get a plan.
Take Curex’s 3-minute allergy quiz. A board-certified allergist will review your symptoms and recommend the right immunotherapy path for you — shots or drops.
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Common Weed SCIT — Frequently Asked
Quick answers to the questions patients ask most before starting treatment.
In US clinical allergy testing, 'common weed' refers to Chenopodium album — the lamb's quarter plant, a globally distributed goosefoot weed. The standard ImmunoCAP code is w10. Different allergy labs and extract manufacturers use different names for the same species: lamb's quarter, common weed, white goosefoot, and fat hen all refer to Chenopodium album. If your lab report says 'common weed' with a positive specific IgE result, you are sensitized to Che a 1 (the major allergen), and the immunotherapy extract used is identical to what allergists prescribe for 'lamb's quarter.' Contact your allergist's office and confirm the ImmunoCAP code (w10) if you are unclear about which species your test measured.
No — common weed (Chenopodium album, Amaranthaceae family) and ragweed (Ambrosia artemisiifolia, Asteraceae family) are botanically unrelated and have completely different major allergens. Che a 1 (lamb's quarter / common weed) is an Ole e 1-like protein; Amb a 1 (ragweed) is a pectate lyase. There is no meaningful cross-reactivity between the two. However, both peak in August-October across most of the US, so patients who are allergic to both (which is common) experience overlapping fall symptoms from two distinct sensitizations. A specific IgE panel that includes both w10 (common weed) and w1 (short ragweed) will clarify which — or both — are contributing to your fall allergy picture.
Different allergy lab systems and extract manufacturers use different common names for Chenopodium album. Quest Diagnostics, LabCorp, and various hospital-based allergy labs may use 'common weed,' 'lamb's quarter,' 'white goosefoot,' or 'fat hen' interchangeably — all for the same Chenopodium album extract under ImmunoCAP code w10. The inconsistency is a quirk of how different US manufacturers named their products historically. The underlying allergen is identical regardless of which common name appears on your report. When comparing results with others, always compare the ImmunoCAP code (w10) rather than the common name to ensure you are looking at the same allergen.
Because common weed = Chenopodium album = lamb's quarter, treatment is identical. A board-certified allergist confirms sensitization via ImmunoCAP w10 or skin-prick test, then prescribes a non-standardized C. album extract for subcutaneous immunotherapy (SCIT). The standard build-up phase involves weekly injections for 3-6 months from a dilute starting concentration to a therapeutic maintenance dose, followed by ongoing maintenance injections for 3-5 years. For polysensitized fall-weed patients, C. album extract is often compounded with Russian thistle, kochia, and pigweed mix in a single vial. Sublingual immunotherapy (SLIT) drops containing C. album extract are an at-home alternative.
Potentially, through the profilin allergen Che a 2 (55% sensitization in Chenopodium-allergic patients). Profilins cross-react with profilins in many raw fruits and vegetables, potentially causing mild oral allergy syndrome — tingling or itching in the mouth — with foods such as melon, banana, tomato, celery, and kiwi during the fall pollen season. However, profilin sensitization is clinically significant in only about 10-20% of pollen-allergic patients. The polcalcin Che a 3 also cross-reacts at the pan-allergen level with polcalcins in other pollens. If you notice oral symptoms with raw foods during fall weed season, mention this to your allergist — it may indicate profilin sensitization requiring additional evaluation.
Yes, in most cases. Chenopodium album SCIT (ImmunoCAP w10, CPT 95115/95117/95165) is covered under standard allergy benefits by major US insurers when prescribed by a board-certified allergist. Prior authorization is commonly required; your allergist's billing office typically handles this. Out-of-pocket cost depends on your plan's deductible, co-insurance, and in-network status. Request a benefits verification before starting to get an accurate estimate of your specific costs.
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.
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