Table 1.
Herbal medicines and their constituents tested for neuropathic pain in human studies
| Substance | Neuropathic disorders | Study type | Results | References |
|---|---|---|---|---|
| A9-Tetrahydrocannabinol/Cannabidiol (THC/CBD) | HIV-associated distal sensory predominant polyneuropathy | Phase II, double-blind, placebo-controlled, crossover trial | Reduced neuropathic pain intensity | (98) |
| THC/CBD | Central neuropathic pain in patients with multiple sclerosis | Randomized controlled trials | Improvement in neuropathic pain without evidence of tolerance | (97) |
| THC/CBD | Patients with intractable cancer-related pain | Multicenter, double-blind, randomized, placebo-controlled, parallel-group study | Reduced neuropathic pain | (99) |
| THC/CBD | Patients with terminal cancer-related pain refractory to strong opioid analgesics | An open-label extension study | Well tolerated and reduced pain | (100) |
| THC/CBD | Patients with peripheral neuropathic pain | A double-blind, randomized, placebo-controlled, parallel group study | Improvement in neuropathic pain | (101) |
| THC/CBD | Patients with peripheral neuropathic pain | A multicentre, open-label, follow-on study | Improvement in neuropathic pain | (102) |
| Aconitum | Patients with diabetic peripheral neuropathic pain | Controlled clinical trials study | Reduced diabetic peripheral neuropathic pain | (105) |
| Citrullus colocynthis | Painful diabetic polyneuropathy patients | Double-blind randomized placebo-controlled clinical trial | Reduced diabetic polyneuropathy pain | (42) |
| Goshajinkigan | Oxaliplatin-induced neuropathy patients | Phase 2, multicenter, randomized, double-blind, placebo-controlled trial | Delayed the onset of grade 2 or greater oxaliplatin-induced neuropathy | (112) |
NMDA: N-methyl-D-aspartate; CNS: central nervous system; PNS: peripheral nervous system; STZ: streptozotocin; ROS: reactive oxygen species; CIPN: chemotherapy drugs that induce peripheral neuropathy; HAE-AC: hydroalcoholic extract of A. calamus; MPO: myeloperoxidase; TST: tibial and sural nerve transection; CCI: chronic constriction injury; TBARS: thiobarbituric acid reactive substances; GSH: glutathione; PDPN: painful diabetic polyneuropathy; 6-OHDA: 6-Hydroxydopamine; PCPA: p-chlorophenylalanine; COX-2: cyclooxygenase 2; MDA: malondialdehyde; SNL: spinal nerve ligation; NOS: nitric oxide synthase; PSNL: partial sciatic nerve ligation; EEPp: ethanolic extract from P. pubescens fruits; THC/CBD, A9-Tetrahydrocannabinol/Cannabidiol; DRG: dorsal root ganglion; 3α-HSOR: 3α-Hydroxysteroid oxidoreductase; SOD: superoxide dismutase