An antimicrobial oral care composition effective against dental plaque, calculus, gingivitis and periodontal disease comprising (a) a cationic antimicrobial agent selected from one or a mixture of quaternary ammonium salts being pyridinium compounds, (b) an anti-stain agent comprising one or more materials from each of at least two of the following chemical groups: (i) Group 1 anionic agents having a molecular weight of 15,000 or less and being selected from a pyrophosphate salt; phytic acid or salt thereof; D-fructose-1-6-biphosphate; D-ribose-5-phosphate; dihydroxyacetone phosphate; D-erythrose-4-phosphate; glycerol phosphate; creatine phosphate; D-ribose-5-phosphate; D-fructose-6-phosphate; D-xylose-5-phosphate; glyceraldehyde-3-phosphate; α-D-glucose-6-phosphate; α-D-glucose-1-phosphate; uridine-5-phosphate; ascorbyl phosphate; carboxymethyl dextran; dextran sulfate; carboxymethyl hydroxypropylcellulose; carboxymethyl methylcellulose or carboxymethyl starch (ii) Group 2 aldehydes, ketones or other reactive carbonyl compounds or (iii) Group 3 nonionic ethoxylated surfactants, wherein the Group 3 anti-stain agents comprise ethoxylated linear alcohols having 18 or more carbons in the alcohol chain, 35 or more ethoxy units and an average molecular weight of about 2,000 to about 15,000, and (c) a pharmaceutically acceptable carrier, wherein the anti-stain agent is present in an amount effective to inhibit dental stain formation caused by the cationic antimicrobial agent. (a) a cationic antimicrobial agent selected from one or a mixture of quaternary ammonium salts being pyridinium compounds, (b) an anti-stain agent comprising one or more materials from each of at least two of the following chemical groups: (i) Group 1 anionic agents having a molecular weight of 15,000 or less and being selected from a pyrophosphate salt; phytic acid or salt thereof; D-fructose-1-6-biphosphate; D-ribose-5-phosphate; dihydroxyacetone phosphate; D-erythrose-4-phosphate; glycerol phosphate; creatine phosphate; D-ribose-5-phosphate; D-fructose-6-phosphate; D-xylose-5-phosphate; glyceraldehyde-3-phosphate; α-D-glucose-6-phosphate; α-D-glucose-1-phosphate; uridine-5-phosphate; ascorbyl phosphate; carboxymethyl dextran; dextran sulfate; carboxymethyl hydroxypropylcellulose; carboxymethyl methylcellulose or carboxymethyl starch (ii) Group 2 aldehydes, ketones or other reactive carbonyl compounds or (iii) Group 3 nonionic ethoxylated surfactants, wherein the Group 3 anti-stain agents comprise ethoxylated linear alcohols having 18 or more carbons in the alcohol chain, 35 or more ethoxy units and an average molecular weight of about 2,000 to about 15,000, and (i) Group 1 anionic agents having a molecular weight of 15,000 or less and being selected from a pyrophosphate salt; phytic acid or salt thereof; D-fructose-1-6-biphosphate; D-ribose-5-phosphate; dihydroxyacetone phosphate; D-erythrose-4-phosphate; glycerol phosphate; creatine phosphate; D-ribose-5-phosphate; D-fructose-6-phosphate; D-xylose-5-phosphate; glyceraldehyde-3-phosphate; α-D-glucose-6-phosphate; α-D-glucose-1-phosphate; uridine-5-phosphate; ascorbyl phosphate; carboxymethyl dextran; dextran sulfate; carboxymethyl hydroxypropylcellulose; carboxymethyl methylcellulose or carboxymethyl starch (ii) Group 2 aldehydes, ketones or other reactive carbonyl compounds or (iii) Group 3 nonionic ethoxylated surfactants, wherein the Group 3 anti-stain agents comprise ethoxylated linear alcohols having 18 or more carbons in the alcohol chain, 35 or more ethoxy units and an average molecular weight of about 2,000 to about 15,000, and (c) a pharmaceutically acceptable carrier,