EVALUATION OF OCULAR DECONGESTANTS IN RABBITS 401 Figure 2. Effect of 5% sodium chloride solution after 1 min. Redness scored three, edema scored one can observe the engorged vessels on the sclera and the involvement of the blood vessels on the lid. This reaction was graded 3 for redness and 1 for edema. ' Other Agonists Histamine PO4, 1:1000, was an unsatisfactory agonist in this assay. How- ever, although some decongestant activity could be demonstratdd, the hyper- enfic condition induced by histamine PO4 was resistant to a significant drug response with any of the preparations tested. The use of water from swimming pools did not consistently produce sufficient hyperemia necessary for drug assays. Ocean water, ho vever, compared favorably with 5% sodium chloride in both the type and severity of irritation induced. Standard Efficacy Test All preparations listed in Table I that contain a vasoconstrictor were effec- tive in eliminating the induced ocular hyperemia within 2 rain of application. These data are presented in Table II. As anticipated, the preparation 'contain- ing a balanced salt solution but no sympathomimetic vas not effective. Also, although effective, the activity of the tetrahydrozoline HC1. preparation was not as complete as the other sympathomimetic formulations. Figure.-3 illus- trates the 2-min effect of 0.1 ml of a preparation containing"1%: hydroxyam-

4O2 JOURNAL OF THE SOCIETY OF COSMETIC CHEMISTS Table II Ocular Decongestant Activity of Commercial Products Effcct Control 15 Sec I Min 9. Min Product A Conjunctival redness 2 I 0 0 Chemosis I 0 0 0 Pupil diameter (mm) 4 4 4 5 Conjunctival redness 2 2 1 0 Chemosis 1 1 0 0 Pupil diatneter (mm) 4 4 4 4 Conjunctival redness 2 2 1 0 Chemosis 1 1 0 0 Pupil diameter (mm) 6 6 6 6 Product B Conjunctival redness 2 2 1 1 Chemosis 0 0 0 0 Pupil diameter (mm) 7 7 7 7 Conjunctival redness 3 3 2 2 Chemosis 1 0 0 0 Pupil diameter (mm) 7 7 7 6 Conjunctival redness 2 1 1 0 Chemosis 1 0 0 0 Pupil diameter (mm) 5 5 5 5 Product C Conjunctival redness 3 2 i 1 Chemosis i 0 0 0 Pupil diameter (ram) 7 7 7 7 Conjunctival redness 2 1 0 0 Chemosis 0 0 0 0 Pupil diameter (mm) 7 7 7 7 Conjunctival redness 2 2 0 0 Chemosis 0 0 0 0 Pupil diameter (mm) 6 6 6 6