Diabetic Peripheral Neuropathy
Direct Answer
The numbness and burning pain in your foot is almost certainly caused by diabetic peripheral neuropathy (DPN), a common complication of diabetes that damages the nerves in your feet and legs due to prolonged high blood sugar levels. 1
Why This Happens
Diabetic peripheral neuropathy affects up to 50% of patients with diabetes and results from metabolic damage to peripheral nerves caused by chronic hyperglycemia 1, 2
The burning pain and numbness represent two different types of nerve fiber damage: small fiber dysfunction causes the burning, tingling, and painful sensations, while large fiber dysfunction produces the numbness and loss of protective sensation 1
Symptoms characteristically start in the toes and progress proximally in a "stocking" distribution, which matches your foot symptoms 3, 1
The pain is typically described as burning, stabbing, or excruciating, often worsening at night 3, 4
Critical Diagnostic Considerations
DPN is a diagnosis of exclusion—other causes must be ruled out including vitamin B12 deficiency, hypothyroidism, renal disease, neurotoxic medications, and inherited neuropathies 1
Up to 50% of DPN cases are asymptomatic but still increase risk for foot ulceration and amputation, so even if you don't feel symptoms, nerve damage may be present 1, 5
Your doctor should perform 10-g monofilament testing plus at least one additional test (pinprick, temperature sensation, or vibration with 128-Hz tuning fork) to confirm the diagnosis 1
Treatment Algorithm
Step 1: Optimize Blood Sugar Control
Achieving HbA1c of 6-7% can slow progression in type 2 diabetes but will NOT reverse existing nerve damage or eliminate established pain 1, 5
Glycemic control is more effective at preventing neuropathy than treating established symptoms 5
Step 2: First-Line Medications for Burning Pain
Start with one of these FDA-approved options 1:
Pregabalin: Proven effective in multiple trials for diabetic neuropathic pain, dosed 100-200 mg three times daily 6
Duloxetine: Improves neuropathy-related quality of life 1
- May cause small increase in HbA1c with long-term use 1
Gabapentin: Dosed 300-1,200 mg three times daily 1
Step 3: Alternative Options if First-Line Fails
Tricyclic antidepressants (amitriptyline): Effective but require monitoring for anticholinergic side effects, especially if you're ≥65 years old 1, 2
Topical capsaicin (8% patch or 0.075% cream): FDA-approved for DPN pain 1
Avoid opioids (tramadol, tapentadol) due to addiction risk for chronic neuropathic pain 1, 5
Essential Preventive Measures
Annual foot examinations with 10-g monofilament testing are mandatory to identify feet at risk for ulceration 3, 1
Comprehensive foot self-care education is critical to prevent ulceration and amputation 3
Control blood pressure aggressively—intensive BP management decreased cardiac autonomic neuropathy risk by 25% in the ACCORD trial 5
Address obesity and consider physical activity/weight loss, which have shown positive effects on DPN 5
Common Pitfalls to Avoid
Do not assume good blood sugar control will eliminate your pain—it only slows progression and does not reverse nerve damage already present 5
Do not ignore symptoms thinking they will resolve—12.5% of patients never report symptoms to their doctor and 39% never receive treatment 3
Start medications at lower doses and titrate slowly, especially if older, to minimize adverse effects 1
Monitor for depression and anxiety—over two-thirds of patients with painful DPN have mood disorders that must be treated concurrently for optimal outcomes 5
If taking thiazolidinedione diabetes medications, be aware that combining with pregabalin increases peripheral edema risk from 8% to 19% 6
When to Seek Urgent Evaluation
- Rapid changes in skin color, new ulcers, deterioration of existing ulcers, signs of infection, or severe pain with redness and swelling require referral to specialized units 3