Comvita Propolis Oral Spray High Strength, 20 Ml.PROPOLIS ORAL SPRAY HIGH STRENGTH, 20 ML. Comvita Propolis Oral Spray Extra Strength supports oral health and helps to freshen the breath. Propolis Oral Spray is the original combination of high quality Propolis, Manuka honey, peppermint, clove and myrrh oils formulated to help maintain oral health and hygiene. Comvita Propolis contains a range of bioflavonoids. The bees create propolis from natural resin produced by trees as part of their defence