Tariquidar-ondansetron Combination in Neuropathic Pain

Inclusion Criteria: 1. Age 18-65; 2. Documented diagnosis of neuropathic pain due to damage or disease affecting the peripheral nervous system; 3. At least Probable neuropathic pain grading1; 4. Pain duration \>3 months; 5. Average pain intensity ≥4 on 0-10 numerical rating scale (NRS). Exclusion Criteria: 1. Current pregnancy or lactation; 2. Moderate-severe kidney or liver dysfunction; 3. Active cardiac arrhythmias (non-sinus rhythm), Long QT syndrome, or QTc interval \>450msec; 4. Congestive heart failure 5. Abnormal troponin values at screening visit; 6. Current treatment with MAO inhibitors, mirtazapine, SSRI antidepressants, or SNRI medications duloxetine or venlafaxine; 7. Current treatment with tapentadol, tramadol, or fentanyl; 8. Current treatment with P-glycoprotein substrate drugs with narrow therapeutic window, e.g. digoxin; 9. Current treatment with tricyclic antidepressant medications (e.g. amitriptyline, desipramine, imipramine) at a dose \>25mg/day; 10. Ongoing use of any of the following medications with known effects on Pgp function: carbamazepine, phenytoin, phenobarbital, cyclosporine, clarithromycin, erythromycin, ritonavir, verapamil, rifampicin, St. John's wort; 11. Current treatment with QT-prolonging drugs, and drugs known to have a significant interaction with ondansetron or other P-glycoprotein substrates (see section 2.3.3.); 12. Current treatment with anticoagulant drugs;