Hi, Travatan Z is composed of Travoprost , which is an ophthalmic solution and is a topical medication. It is used for controlling the progression of glaucoma or ocular hypertension, by reducing intraocular pressure. It is a synthetic prostaglandin analogue that works by increasing the outflow of aqueous fluid from the eyes. Possible side effects are blurred vision, eyelid redness, permanent darkening of eyelashes and eye discomfort. Eye discomfort and burning sensation during use can cause difficulty in getting sleep. Cosopt is a combination of Dorzolamide and timolol eye drops. They are used to lower intraocular pressure in the eye to normal pressure and as a treatment for glaucoma. Both compounds work by decreasing the production of aqueous humor, which works to lower intraocular pressure. Common adverse effects include temporarily blurred vision, cloudy vision, double vision, temporary burning/stinging/itching of the eye, and watery eyes. More serious adverse effects include dizziness, slow or irregular heartbeat, muscle weakness, mental/mood changes, and coldness/numbness/pain in the hands or feet. Many of these effects could be due to timolol , which is a non-selective beta-adrenergic antagonist. Kindly consult your doctor if these side effects persist and become bothersome. Hope I have answered your query. Let me know if I can assist you further. Take care Regards, Dr Ashakiran S, General & Family Physician