"The free acid or base is responsible for the drug's therapeutic effect. Hence, the salt form of a drug has the same mechanism of action as the free acid or base form."^^ . "Used to associate the salt form of a drug with its free acid or free base.NCI" . "Conceptual Entity"^^ . "Has_Free_Acid_Or_Base_Form"^^ . "Has_Free_Acid_Or_Base_Form"^^ . "Has_Free_Acid_Or_Base_FormPTNCI" . "Has Free Acid Or Base Form"^^ . "A6"^^ . . .