12379
Presently , little is known about a number issues concerning kava ( Piper methysticum ) , including ( i ) whether kava has any withdrawal or addictive effects ; ( ii ) if genetic polymorphisms of the cytochrome ( CYP ) P450 2D6 liver enzyme moderates any potential adverse effects ; and ( iii ) if medicinal application of kava has any negative or beneficial effect on sexual function and experience .
 None
Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: Chemical 
Text: {0} 
Answer:
 None