Ophthalmic compositions are provided that comprise or consist essentially of (a) ketotifen or a ketotifen salt, (b) a non-ionic tonicity agent, and (c) water. The concentration of ketotifen or the ketotifen salt is preferably from 0.01 % to 0.05 %. The non-ionic tonicity agent is preferably glycerol and the concentration of the glycerol is preferably from 4 % to 7 %. The compositions preferably have an osmolality of from 400 to 875 milliosmoles/Kg. The compositions may also contain an anti-redness agent. Methods of treating allergic conjunctivitis using the ophthalmic compositions and methods of treating dry eye disease using the ophthalmic compositions are also provided.