Numbness in Hands and Feet — Common Causes and What to Do

That Tingling Isn't Something to Ignore

Numbness, tingling, pins-and-needles, burning — when these sensations show up in your hands and feet and don't go away, your nerves are trying to tell you something. Peripheral neuropathy (nerve damage in the extremities) affects over 20 million Americans, and many cases go undiagnosed for years.

Let's talk about what causes it and when to act.

The Most Common Causes

1. Diabetes and Pre-Diabetes

This is the #1 cause of peripheral neuropathy in the United States. High blood sugar damages small blood vessels that supply nerves, leading to:

• Numbness starting in the toes and gradually moving up
• Burning or tingling, often worse at night
• Loss of sensation (not feeling cuts or injuries on feet)

The missed diagnosis: Many people with neuropathy have pre-diabetes (A1C 5.7–6.4%) or early diabetes they don't know about. Nerve damage can start before blood sugar reaches "diabetic" levels.

What to test: Fasting glucose, hemoglobin A1C, fasting insulin, oral glucose tolerance test

2. Vitamin B12 Deficiency

B12 is essential for nerve health. Deficiency causes:

• Numbness and tingling in both hands and feet (symmetric)
• Balance problems
• Fatigue and brain fog
• Anemia (though neuropathy can occur before anemia develops)

Who's at risk:

• Vegetarians and vegans (B12 comes primarily from animal products)
• People on metformin (depletes B12 over time)
• People on acid-blocking medications (PPIs like omeprazole)
• Adults over 60 (absorption decreases with age)
• Anyone with GI conditions affecting absorption

What to test: Serum B12 (but note: "low-normal" B12 can still cause symptoms), methylmalonic acid (more sensitive test)

3. Carpal Tunnel Syndrome

If numbness is primarily in your hands — especially the thumb, index, and middle fingers — and worsens at night or with repetitive hand use, carpal tunnel is likely.

This is nerve compression, not nerve damage. The median nerve gets squeezed as it passes through the wrist. Common in:

• Desk workers
• Manual laborers
• Pregnant women
• People with thyroid disorders or diabetes

4. Alcohol-Related Neuropathy

Chronic heavy alcohol use directly damages peripheral nerves. The damage is often:

• Symmetric (both sides equally)
• Starts in the feet
• Burning or painful
• Accompanied by nutritional deficiencies (thiamine, folate, B12)

Alcohol-related neuropathy may improve with cessation, but long-standing damage can be permanent.

5. Medication Side Effects

Several common medications cause peripheral neuropathy:

• Chemotherapy drugs (especially platinum-based and taxanes)
• Statins (rare but documented)
• Metformin (via B12 depletion)
• Fluoroquinolone antibiotics (Cipro, Levaquin)
• Some HIV medications
• Excessive B6 supplementation (paradoxically, too much B6 causes neuropathy)

If numbness started after beginning a new medication, report this to your doctor.

6. Thyroid Dysfunction

Both hypothyroidism and hyperthyroidism can cause peripheral neuropathy. Hypothyroidism is more common and causes:

• Tissue swelling that compresses nerves (like carpal tunnel)
• Direct nerve damage from metabolic changes
• Often improves with thyroid treatment

7. Autoimmune Conditions

Several autoimmune diseases attack peripheral nerves:

• Guillain-Barre syndrome — acute, ascending weakness and numbness (medical emergency)
• Chronic inflammatory demyelinating polyneuropathy (CIDP) — chronic version
• Lupus — can cause neuropathy as part of widespread inflammation
• Sjogren's syndrome — commonly causes small-fiber neuropathy
• Celiac disease — gluten-related nerve damage

Red Flags: When Numbness Is an Emergency

Go to the ER if numbness is accompanied by:

• Sudden weakness on one side of the body (possible stroke)
• Rapid onset over hours to days with ascending weakness (possible Guillain-Barre)
• Loss of bladder or bowel control (possible spinal cord compression)
• Numbness after injury to the neck or back
• Severe pain with sudden onset

The Diagnostic Workup

Your doctor should order:

Blood work:

• Fasting glucose and A1C
• B12 and methylmalonic acid
• Complete metabolic panel
• Thyroid panel
• CBC
• Vitamin D
• Inflammatory markers (ESR, CRP)
• ANA (autoimmune screening)
• Folate, thiamine
• Heavy metal panel (if exposure suspected)

Additional testing if indicated:

• Nerve conduction studies/EMG — measures how well nerves are conducting signals
• MRI — if spinal cord compression suspected
• Nerve biopsy — rare, for unusual cases

Treatment Depends on the Cause

Diabetic neuropathy:

• Blood sugar control is priority #1
• Medications for nerve pain (gabapentin, pregabalin, duloxetine)
• Alpha-lipoic acid (some evidence for benefit)
• Medical marijuana (effective for neuropathic pain in many patients)

B12 deficiency:

• B12 supplementation (often injections initially, then oral)
• Symptoms often improve within weeks to months

Carpal tunnel:

• Wrist splints (especially at night)
• Ergonomic modifications
• Steroid injections
• Surgery if conservative treatment fails

Medication-induced:

• Dose reduction or medication change
• Nerve healing can take months after the offending drug is stopped

General nerve pain management:

• Gabapentin or pregabalin
• Duloxetine (Cymbalta)
• Topical capsaicin or lidocaine
• Medical cannabis (particularly effective for neuropathic pain)
• Physical therapy and exercise

Don't Wait

Peripheral neuropathy is progressive in many cases. The earlier you identify the cause and start treatment, the better your chances of preventing permanent nerve damage.

At Coral, we evaluate numbness and tingling through comprehensive telehealth evaluations, including targeted lab work to identify treatable causes. If medical marijuana is appropriate for nerve pain management, we can address that too.

[Book your evaluation](/start) — find the cause before nerve damage becomes permanent.