---
title: "Which blood tests should you get for itching without a rash?"
type: symptom
url: "https://www.test-well.com/symptoms/itchy-skin"
symptom: Itchy skin without a rash
aliases:
  - itchy skin blood test
  - itching all over no rash blood test
  - pruritus lab work
  - itching liver kidney thyroid test
reviewed_at: 2026-09-06
review_status: reviewed
date_published: 2026-09-07
lab_fee_usd: 6
---

# Which blood tests should you get for itching without a rash?

> Itching all over without a visible rash is the presentation where blood tests earn their keep: liver disease (bile-salt itch), kidney disease, iron deficiency, thyroid disorders, diabetes, and blood conditions such as polycythemia and lymphoma can all cause it. A comprehensive metabolic panel, CBC, ferritin, TSH and A1c cover the common ones. Itching with yellow skin, night sweats or weight loss needs a clinician promptly.


## When should you see a clinician instead of ordering a test?

- Itching with yellow skin or eyes, dark urine or pale stools — see a clinician promptly
- Itching with night sweats, fever, unexplained weight loss or swollen lymph nodes
- Hives with lip or tongue swelling, wheeze or trouble breathing — call 911
- Itching in pregnancy, especially palms and soles, in the third trimester — same-week evaluation (cholestasis of pregnancy)

## Why these tests for itchy skin without a rash?

A comprehensive metabolic panel checks liver enzymes, bilirubin and kidney function — cholestatic liver disease and advanced kidney disease are two well-recognized causes of generalized itch. A GGT or hepatic panel adds detail if liver values are abnormal.

Iron deficiency causes itch even without anemia, so ferritin is checked alongside a CBC; the CBC also screens for polycythemia (itch after warm showers) and abnormal white cells. TSH covers both hypo- and hyperthyroidism, which itch through different mechanisms.

A1c screens for diabetes, which dries and irritates skin; allergy-related itch is usually visible, but total IgE and tryptase are sometimes added when hives come and go.

## Which conditions do these tests help evaluate?

- [Fatty Liver](https://www.test-well.com/conditions/fatty-liver) — Liver enzymes, metabolic and lipid markers to assess fatty liver risk.
- [Anemia](https://www.test-well.com/conditions/anemia) — CBC, iron studies, ferritin, B12 and folate to find the cause of fatigue and low energy.
- [Thyroid Problems](https://www.test-well.com/conditions/thyroid-problems) — TSH, Free T4/T3 and antibodies to evaluate an under- or over-active thyroid.
- [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 |
| --- | --- | --- | --- | --- | --- |
| [General Wellness Panel](https://www.test-well.com/tests/general-wellness-panel) | Panel (4 tests) | $89.99 | $95.99 | Yes | 1–3 business days |
| [Baseline Anemia Panel](https://www.test-well.com/tests/anemia-panel) | Panel (5 tests) | $74.99 | $80.99 | Yes | 2–4 business days |
| [Complete Thyroid Panel](https://www.test-well.com/tests/thyroid-complete-panel) | Panel (4 tests) | $109.99 | $115.99 | No | 3–7 business days |
| [Comprehensive Metabolic Panel](https://www.test-well.com/tests/comprehensive-metabolic-panel) | Test | $22.99 | $28.99 | Yes | 1–3 business days |
| [Liver Function Panel](https://www.test-well.com/tests/hepatic-function-panel) | Test | $19.99 | $25.99 | No | 1–3 business days |
| [CBC with Differential](https://www.test-well.com/tests/cbc-with-differential) | Test | $21.99 | $27.99 | No | 1–3 business days |
| [Ferritin](https://www.test-well.com/tests/ferritin) | Test | $24.99 | $30.99 | No | 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 |
| [Hemoglobin A1c](https://www.test-well.com/tests/hemoglobin-a1c) | Test | $21.99 | $27.99 | No | 2–4 business days |
| [GGT (Gamma-Glutamyl Transferase)](https://www.test-well.com/tests/ggt) | Test | $19.99 | $25.99 | No | 1–3 business days |
| [Tryptase](https://www.test-well.com/tests/tryptase-test) | Test | $71.99 | $77.99 | No | 3–5 business days |

Prices are cash-pay; every order adds one $6.00 lab processing fee. Physician authorization included.

## Common questions

### Why would I itch all over with no rash?

Generalized itch without a rash points inward: liver, kidney, iron, thyroid, diabetes, medications and, less commonly, blood disorders. Dry skin and aging skin are the everyday causes; labs are how the internal ones are excluded.

### Which liver test shows itching?

There isn't one specific test; itch tracks with bile-acid buildup, so alkaline phosphatase, bilirubin and GGT on a hepatic panel are the relevant markers. Serum bile acids can be added by a clinician.

### Can low iron cause itching?

Yes — iron deficiency is an under-recognized cause of generalized itch and can occur with a normal hemoglobin. Ferritin is the test; repletion usually resolves it within weeks.

## 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 Dermatology — Itchy skin: 10 reasons your skin itches](https://www.aad.org/public/everyday-care/itchy-skin/itch-relief/relieve-uncontrollably-itchy-skin)
- [NIDDK — Symptoms and causes of liver disease (cholestasis)](https://www.niddk.nih.gov/health-information/liver-disease)

---

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/itchy-skin
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.