Objectives : This research study compared the efficacy of three anti-allergic preparations commonly used in the treatment of allergic conjunctivitis. Materials and Method : A randomized, double-masked, placebo-controlled multicenter study was conducted for four weeks in 4 centers to evaluate the efficacy of topical Antazoline (0.5mg), Sodium Cromoglycate (20mg) and Lodoxamide (1.78mg) for the treatment of active bilateral allergic conjunctivitis. Sixty patients diagnosed with allergic conjunctivitis completed the study; they were divided into four groups of 15 each. Group A was treated with a masked bottle of 0.5mg Antazoline (Spersallerg eyedrop) labelled ‘R’, Group B was treated with a masked bottle of 20mg Sodium Cromoglycate (Ivycrom eyedrop) labelled ‘S’, Group C was treated with a masked bottle of 1.78mg Lodoxamide (Alomide eyedrop) labelled ‘T’ and Group D was treated with a matching placebo (the drug vehicle). Objective clinical signs were graded weekly by the clinicians while patients kept a daily record of the severity of their symptoms. Results : 1.78mg Lodoxamide was found to be more effective than 20mg Sodium Cromoglycate and 0.5mg Antazoline in treating the signs and symptom of allergic conjunctivitis to a statistically significant level (p<0.001). The least effective of these three eyedrops is 0.5mg Antazoline, although it was found to be significantly more effective than the placebo in treating the signs and symptoms of allergic conjunctivitis. Conclusion : It was clear that patients with allergic conjunctivitis responded better to 1.78mg Lodoxamide therefore 1.78mg Lodoxamide has the highest efficacy and it may be a recommended drug in the management of allergic conjunctivitis. Keywords : 0.5mg Antazoline, 20mg Sodium Cromoglycate, 1.78mg Lodoxamide, Allergic conjunctivitis.