Table 5.

The different phytochemicals effective in various neurological diseases and their current clinical phase status.

Sr #	Phytochemicals	Source	Family	Disease	Mechanism	Development stage	Trade Name	Reference
1	Cannabidiol	Cannabis sativa	Cannabaceae	Epilepsy	Modulation of intracellular calcium and neuronal inhibition	FDA approved, 2018	Epidiolex as 5- 10 mg/kg/day	[189]
2	Cannabidol	Cannabis sativa L.	Cannabaceae	Chronic Neuropathic pain	CB1 and CB2 receptor activation	FDA approved, 2005	Sativex Spray (CBD 25mg/ml + THC27mg/ml)	[190]
3	Capsaicin	Capsicum annum L.	Solanaceae	Postherpetic neuralgia	TRPV1 activator	FDA approved, 2010	Qutenza as Patch (179mg capsacin)	[190]
4	Curcumin	Curcuma longa	Zingiberaceae	Dementia	Anti-amyloid, AChEI	phase II		[191]
5	Galantamine	Galanthus nivalis	Amaryllidaceae	Alzheimer	AChEI, allosteric modulation of nicotinic ACh receptor	FDA approved, 2004	Razadyne as 8-12 mg BD	[192]
6	Huperzine A	Huperzia serrata	Huperziaceae	Alzheimer	AChEI, inhibits NMDA and glutamate toxicity	approved in China		[193]
7	Ibogaine	Tabernanthe iboga	Apocynaceae	Parkinson	Dopaminergic agonist, NMDA antagonism	preclinical		[193]
8	Psychollatine	Psychotria umbellate	Rubiaceae	Parkinson	MAO inhibitor	preclinical		[193]
9	Resveratrol	Vitis vinifera L.	Vitaceae	Alzheimer	Reduces Aβ formation and promote Aβ decomposition	phase II		[194]
10	Scyllo-Inositol	Cornus florida L.	Cornaceae	Alzheimer	Breakdown of neurotoxic fibrils, allowing amyloid peptides to clear the body rather than form amyloid plaques	phase II		[195]

FDA: food and drug administration; TRPV1: transient receptor potential vanilloid 1; CB1 and CB2: cannabinoid receptor type 1 & type 2; Ach: acetylcholine; AChEI: acetylcholinesterase inhibitor; CBD: cannabidiol; THC: tetrahydrocannabinol; BD: bis in die; NMDA: N-methyl-D-aspartate; MAO: monoamine oxidase; Aβ: amyloid beta.