--- title: "Which blood tests should you get for restless legs?" type: symptom url: "https://www.test-well.com/symptoms/restless-legs" symptom: Restless legs aliases: - restless legs blood test - restless legs iron test - RLS ferritin level - restless leg syndrome lab work reviewed_at: 2026-09-06 review_status: reviewed date_published: 2026-09-07 lab_fee_usd: 6 --- # Which blood tests should you get for restless legs? > Restless legs syndrome has one lab that changes management: ferritin. Brain iron is low in RLS, and guidelines recommend iron repletion when ferritin is below about 75 ng/mL even if hemoglobin is normal. A CBC, kidney function (metabolic panel), TSH, vitamin B12, folate, vitamin D and magnesium cover the other contributors. Kidney failure, pregnancy and several medications also cause or worsen RLS. ## When should you see a clinician instead of ordering a test? - Leg symptoms with numbness, weakness, or loss of bladder or bowel control — urgent evaluation - Swelling, warmth or pain in one calf (possible clot) - Restless legs that started after a new medication — antihistamines, antidepressants and anti-nausea drugs are common triggers; ask the prescriber before stopping ## Why these tests for restless legs? Iron is central: ferritin below ~75 ng/mL is associated with more severe RLS, and treating it improves symptoms — the transferrin saturation from an iron panel helps guide the decision. A CBC shows whether anemia has developed. Kidney disease is a major secondary cause; a metabolic panel screens kidney function. Hypothyroidism, B12 and folate deficiency, and low vitamin D and magnesium are each associated with RLS or leg discomfort and are correctable. A1c matters because diabetic nerve damage causes leg sensations that are treated differently from RLS. ## Which conditions do these tests help evaluate? - [Anemia](https://www.test-well.com/conditions/anemia) — CBC, iron studies, ferritin, B12 and folate to find the cause of fatigue and low energy. - [Insomnia & Poor Sleep](https://www.test-well.com/conditions/insomnia) — Cortisol, thyroid, vitamin D and metabolic markers tied to disrupted sleep. - [Diabetes & Blood Sugar](https://www.test-well.com/conditions/diabetes-screening) — A1c, fasting glucose and insulin to screen for prediabetes and diabetes. ## Which tests, and what do they cost? | Test or panel | Type | Price | All-in (one item + $6 fee) | Fasting | Results | | --- | --- | --- | --- | --- | --- | | [Baseline Anemia Panel](https://www.test-well.com/tests/anemia-panel) | Panel (5 tests) | $74.99 | $80.99 | Yes | 2–4 business days | | [Sleep Health Panel](https://www.test-well.com/tests/sleep-health-panel) | Panel (8 tests) | $129.99 | $135.99 | Yes | 3–5 business days | | [Vitamin & Mineral Deficiency Panel](https://www.test-well.com/tests/vitamin-mineral-panel) | Panel (9 tests) | $189.99 | $195.99 | No | 3–5 business days | | [Ferritin](https://www.test-well.com/tests/ferritin) | Test | $24.99 | $30.99 | No | 1–3 business days | | [Iron Panel (Iron, TIBC & Ferritin)](https://www.test-well.com/tests/iron-panel-complete) | Test | $32.99 | $38.99 | Yes | 2–5 business days | | [CBC with Differential](https://www.test-well.com/tests/cbc-with-differential) | Test | $21.99 | $27.99 | No | 1–3 business days | | [Comprehensive Metabolic Panel](https://www.test-well.com/tests/comprehensive-metabolic-panel) | Test | $22.99 | $28.99 | Yes | 1–3 business days | | [TSH (Thyroid Stimulating Hormone)](https://www.test-well.com/tests/tsh) | Test | $26.99 | $32.99 | No | 1–3 business days | | [Vitamin B12](https://www.test-well.com/tests/vitamin-b12) | Test | $25.99 | $31.99 | No | 2–4 business days | | [Folate (Vitamin B9)](https://www.test-well.com/tests/folate) | Test | $32.99 | $38.99 | No | 2–4 business days | | [Vitamin D, 25-Hydroxy](https://www.test-well.com/tests/vitamin-d) | Test | $41.99 | $47.99 | No | 1–3 business days | | [Magnesium](https://www.test-well.com/tests/magnesium) | Test | $19.99 | $25.99 | No | 2–4 business days | | [Hemoglobin A1c](https://www.test-well.com/tests/hemoglobin-a1c) | Test | $21.99 | $27.99 | No | 2–4 business days | Prices are cash-pay; every order adds one $6.00 lab processing fee. Physician authorization included. ## Common questions ### What ferritin level is recommended for restless legs? Guidelines suggest treating iron when ferritin is under 75 ng/mL (some use 50) and transferrin saturation is under 20–45%, even without anemia. That is well above the lab's 'normal' cutoff, which is why a normal CBC does not rule out iron as the cause. ### Can a blood test diagnose restless legs syndrome? No — RLS is diagnosed from the symptom pattern: an urge to move the legs, worse at rest and in the evening, relieved by movement. Labs find the reversible contributors, iron above all. ## Related - [What blood tests should you get for fatigue?](https://www.test-well.com/symptoms/fatigue) - [Which blood tests help explain brain fog?](https://www.test-well.com/symptoms/brain-fog) - [What blood tests should you get for hair loss?](https://www.test-well.com/symptoms/hair-loss) - [What blood tests check for causes of unexplained weight gain?](https://www.test-well.com/symptoms/weight-gain) - [All symptoms](https://www.test-well.com/symptoms) - [Browse by condition](https://www.test-well.com/conditions) ## Sources - [American Academy of Sleep Medicine — Treatment of restless legs syndrome (2024 guideline: iron)](https://aasm.org/clinical-resources/practice-standards/practice-guidelines/) - [NINDS — Restless legs syndrome](https://www.ninds.nih.gov/health-information/disorders/restless-legs-syndrome) --- Medically reviewed by Youmna DiStefano, MD (Medical Reviewer, TestWell); last reviewed 2026-09-06. Review policy: https://www.test-well.com/editorial-policy Canonical page: https://www.test-well.com/symptoms/restless-legs Machine-readable catalog: https://www.test-well.com/api/catalog.json · MCP server: https://www.test-well.com/mcp · Overview for agents: https://www.test-well.com/llms.txt Prices are cash-pay, in USD, and include physician authorization; every order adds one flat $6 lab processing fee. Educational content is not a diagnosis — discuss results with a clinician.