Brief Answer: You need to use both the eye drops. Detailed Answer: Hello Welcome to Health Care Magic Iam Dr. Dadapeer K, an Ophthalmologist and I answer health problems related to eye. It seems from the history that you are having eye infection with symptoms of irritation, redness and discharge following sinus infection. These symptoms indicate that you are having conjunctivitis. Conjunctivitis is infection of conjunctiva by microbial organisms. It is common following or with sinus infection because of spread of the infection from the surrounding structures. The treatment is by using antibiotic eye drops. The usual protocol is to use antibiotics which covers gram positive and gram negative organisms. The drops you are prescribed, Fucithamic eye drops contain fusidic acid and it is active against gram positive organisms. Hence it is better that you use one more antibioitc which is active against gram negative organisms. Polymyxin eye drops is active against gram negative and you can use it. Tobramycin is better and safer alternative to polymyxin. You need to the antibiotic eye drops as frequently as once in a hour for the affected eye. Since the infection invariably spreads to the other eye you need to use the eye drops to other eye. The infection may spread to other people at home hence you need to take precautions like Avoiding close contact with others till the infection is reduced Using separate kerchiefs, towels, bed sheets... to prevent spread of infection Hope I have answered your questions and the answer is helpful to you. Thank you

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