Often times whe indoor plants start to drip sticky sap (honeydew) on to the plant and surrounding areas it is due to the presence of and insect most likely scale or mealy bug. Scale looks like hard black raised spots on the leaves, stems etc of the plant and mealy bug looks like cotten tufts on the stems and leaf parts. As the insect feeds they give off a sugary substance. They are difficult to control if numerous. Whit your plant I suggest moving it to a spot where it can be treated and about the only thing you could use for interior plants is either and insecticidal soap or a horticultural oil (not dormant oil) such as Sunspray. You would have to spray entire plant thoroughly and then make repeat applications about every 10-14 days. If badly infested it may be better to replace the plant.