Multi-purpose contact lens care compositions

A multi-purpose solution for contact lens care comprising:

• an aqueous liquid medium;
• an antimicrobial component in an amount effective to disinfect a contact lens contacted with said solution, said antimicrobial component being selected from the group consisting of biguanides, biguanide polymers, salts thereof and mixtures thereof, and being present in an amount in a range of about 0.1 ppm to about 3 ppm;
• a poly(oxyethylene)-poly(oxypropylene) block copolymer surfactant in an amount effective in cleaning a contact lens contacted with said solution;
• a phosphate buffer component in an amount effective in maintaining the pH of said solution within a physiologically acceptable range;
• hydroxypropylmethylcellulose in an effective viscosity inducing amount in a range of about 0.05% to about 0.5% (w/v);
• a chelating component selected from the group consisting of ethylenediaminetetraacetic acid, alkali metal salts of ethylenediminetetraacetic acid and mixtures thereof in an effective amount of less than 0.05%(w/v);
• and
• a tonicity component, including chloride, in an amount effective in providing the desired tonicity to said solution, said solution having enhanced overall performance ratings relative to another multi-purpose solution containing an aqueous liquid medium, 0.5 ppm polyhexamethylene biguanide, a poly (oxyethylene)-poly(oxypropylene) substituted ethylenediamine surfactant, a borate buffer system, 0.1% w/v disodium EDTA and a sodium chloride tonicity agent in a randomized, double-masked, three-way crossover study.