Phase IV Trial to Evaluate Efficacy of Alpha-Lipoic Acid in Treating Symptomatic Diabetic Polyneuropathy in Egypt

Inclusion Criteria: 1. Signed informed consent form. 2. Male or female patients aged ≥ 18 and ≤ 64 years. 3. Type 2 diabetes mellitus (T2DM) patients as defined according to the American Diabetes Association (ADA) criteria with diabetes duration ≥ 1 year. 4. Hemoglobin A1c (HbA1c) ≤10%. 5. Patients with symptomatic distal symmetrical polyneuropathy (DSPN) attributable to diabetes; after a thorough evaluation for other causes of neuropathy, with evidence of polyneuropathy based on abnormal peripheral nerve function according to clinical and electrophysiological examinations. 6. Patients treated with oral antidiabetic drugs and/or insulin. 7. Patients with the treatment regimen, weight, diet, and physical activity level relatively acceptable as judged by the investigator within 1 month prior to study entry. 8. Patients with working telephone numbers. Exclusion Criteria: 1. Female patients with child-bearing potential not using effective birth control methods including oral contraceptives with a stable regimen for at least 2 months, depo-medroxyprogesterone, a barrier method alone (diaphragm, condoms, or contraceptive sponge with spermicidals), or an intrauterine device that has been in place for at least 2 months. 2. Patients with neuropathies other than DSPN; myopathy and other neurologic diseases that might interfere with the assessment of the severity of DSPN. 3. Patients with a recent history of drug or alcohol abuse; within 1 year prior to study entry. 4. Patients with a history of peripheral vascular disease and/or foot ulcers. 5. Patients with a history of organ transplantation. 6. Patients with a history of cardiovascular, pulmonary, gastrointestinal, hematologic, or endocrine disease, or malignancy that cause neuropathic pain. 7. Hospitalization due to hypoglycemia or ketoacidosis within 3 months prior to study entry. 8. Patients with significant hepatic or renal disease \[Serum creatinine \> 1.8 mg/dL for men and \> 1.6 mg/dL for women, Aspartate aminotransferase (AST) or alanine aminotransferase (ALT) ≥ 3 times upper limit of normal (ULN)\]. 9. Use of medications indicated for neuropathic pain relief within 15 days (washout period) prior to study entry. For analgesia, standard doses of salicylates, ibuprofen, indoles, fenamates, oxicams, or pyrazoles are allowed. 10. Use of antioxidants (including but not limited to vitamin E, vitamin C, and β-carotene) or pentoxifylline within 1 month prior to study entry. 11. Use of medications or vitamins known to cause peripheral neuropathy including but not limited to the use of phenytoin or carbamazepine over 15 or more years, or use of pyridoxine \> 100 mg/d within 12 months prior to study entry. 12. Use of ≥ 50 mg ALA or use of alpha-linolenic acid-containing substances within 3 months prior to study entry. 13. Use of an investigational drug within 6 months prior to study entry. 14. Enrollment in any other clinical trial during the time of this trial.