A composition comprises a polyorganosiloxane and an admixed hindered amine light stabilizer (HALS) wherein the polyorganosiloxane is free from alternating cyclic hydrocarbon residues. A method of stabilizing a polyorganosiloxane composition comprises providing a polyorganosiloxane and admixing a HALS with the polyorganosiloxane. A light bulb comprises an enclosure coated with a polyorganosiloxane composition containing a HALS.