Xalacom is a combination eye drop containing latanoprost and timolol maleate. Latanoprost is a prostaglandin F analogue. Xalacom is a sterile, isotonic solution containing 50 microgram/mL of latanoprost and 5 mg/mL of timolol (6.83 mg timolol maleate) in an aqueous buffer solution of pH 6.0.