Rheumatoid Factor (IgG)
An antibody linked to rheumatoid arthritis and related autoimmune joint disease.
Consider this test if:
- Persistent joint pain, swelling, or morning stiffness lasting more than 30 minutes
- Working up suspected rheumatoid arthritis or another autoimmune joint condition
- A prior positive rheumatoid factor that needs isotype-level characterization
- Symmetric small-joint symptoms in the hands, wrists, or feet
Currently unavailable in your state.
This test isn't offered by labs in your state yet.
Pre-test considerations
A routine blood draw. Overnight fasting is preferred but not strictly required, and results are interpreted with your symptoms and related antibody tests rather than in isolation.
Video consult with your Care Team
A 1:1 call to discuss your health.
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What this test is for
Rheumatoid factor is an autoantibody that targets the body's own immunoglobulins, and its presence supports the diagnosis of rheumatoid arthritis when joint pain, morning stiffness, and swelling are present. This test measures the IgG isotype of rheumatoid factor specifically, while the standard rheumatoid factor test captures the more common IgM-dominant total and the RF Titer version reports the same total as a dilution endpoint. A positive result is interpreted alongside symptoms and other markers, since rheumatoid factor also appears in other autoimmune conditions, chronic infections, and in some healthy people, particularly with age. A negative result does not exclude rheumatoid arthritis, which is why anti-CCP antibodies and inflammatory markers like CRP are often checked together.
- Specimen
- Serum
- Measures
- Concentration
What you'll learn
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Insights that connect the dots. A clinician reads your whole picture, not one result in isolation, connecting family history, past results, and lifestyle into clear next steps.
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Your personalized action plan. Nutrition, supplements, and training in one clinician-reviewed protocol, updated as your results change.
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Track your trends. Upload results from any lab and see each biomarker trend over time, so you know what is working.
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Never miss a recheck. Mito tells you what is worth retesting and when, then reminds you so nothing slips.
What to expect
- 1 Book instantly
Click, book, done. Choose a convenient lab location near you. Transparent, up-front pricing.
- 2 Quick lab visit
Testing to fit your busy schedule, usually 15 minutes or less. Walk-in and appointments available.
- 3 Typical results in about 1 week
Your results post straight to your dashboard as soon as the lab completes them.
- 4 Expert guidance
Included with Mito membership. A clinician reviews your results and your personalized action plan follows, with clear next steps.
Everything your health needs,
in one membership
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Every test at our cost
Members pay our cost on every test, with lab fees passed straight through. The full receipt is itemized, never padded.
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Continuous tracking, all in one place
Upload past labs and watch your trends over time. Every marker and visit lives in one longitudinal record, so all your care stays together.
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Year-round clinician support
Text anytime and get clinician-reviewed answers. When you want to go deeper, 1:1 consultations are available at affordable rates.
All for $9/month
Order any test or consult without joining. For $9/month, members unlock member prices, trend tracking, and year-round clinician guidance.
Mito Membership
$9 /mo
cancel anytime
Without membership
$0
pay as you go
At-cost pricing on labs, scans, and more
Priority turnaround on your results
On-demand clinician consults when you need guidance
Personalized action plans across supplements, exercise, nutrition, and sleep
AI health coaching to help you act on your results
Year-round medical support, with in-chat clinician escalation
All your health records in one personal vault, with trends and biological age tracking
Early access to new diagnostics and product releases
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Frequently asked questions
View all FAQsHow does pricing work?
Every test shows the member price next to the standard non-member price, so you can see what membership saves you. The member price is our cost, covering the lab and what it takes to run the service. It is never a profit on the test itself. Mito makes its money on the $9 membership, not on marking up your tests. Membership is $9 per month, and any applicable lab order or draw fee is itemized before you pay.
Where do I get tested?
Choose an available partner lab at checkout. If your cart contains multiple blood tests, Mito helps consolidate the eligible tests at one lab when possible. At-home kits and scans follow the collection or appointment process shown on their product page.
Is this eligible for HSA/FSA?
Yes. Eligible tests can be paid for with an HSA or FSA card at checkout.
When will I get my results?
Your results appear in your Mito dashboard after the laboratory completes processing. A clinician then reviews them before your analysis and personalized action plan are finalized. Timing varies by test, and specialty assays and at-home kits may take longer.
Do I need a doctor's order?
No. Mito provides the laboratory order when one is required, so you do not need to arrange a separate doctor visit before purchasing.
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