When is a blood test recommended for peripheral neuropathy?

Peripheral neuropathy affects nerves outside the brain and spinal cord. It may cause tingling, numbness, burning pain, sensitivity to touch, balance problems, or weakness, often in the feet or hands. Blood tests cannot measure every nerve problem, but they can identify conditions that may injure nerves or make symptoms worse.

Depending on your symptoms and examination, a clinician may assess blood glucose, vitamin levels, thyroid function, kidney or liver health, and blood counts. The pattern and duration of symptoms guide the choice of tests. Further assessment, such as nerve studies, may be considered when blood tests do not explain the problem.

Write down when symptoms began, where they occur, whether they are spreading, and what makes them better or worse. Bring a list of medicines, supplements, alcohol use, and existing conditions. Follow any instructions about fasting, and do not take extra vitamins to alter a result unless a clinician advises it.

Arrange prompt medical review for new or worsening numbness, burning pain, or weakness. Seek emergency help for sudden one-sided weakness, facial drooping, trouble speaking, severe breathing difficulty, or loss of bladder or bowel control, as these may indicate a different urgent problem.

Which causes are you checking with the blood tests? Do I need to fast? Could a medicine or supplement affect my symptoms? If results are normal, what examination or nerve testing comes next?