Glaucoma is one of the leading causes of blindness , second to cataract. Lowering intraocular pressure is the most effective therapeutic means for this disease, with prostaglandin analogs as the first-line medication. These drugs are efficacious and safe, with well-tolerated local adverse effects. They are also generally regarded to have almost no systemic untoward effect. Nonetheless, with the continuous rise in their popularity, systemic adverse effects caused by topical ocular use of prostaglandins have attracted increasing attention. These adverse effects include digestive, respiratory, and cardiovascular systems, as well as skin and hair. Although the incidence of these adverse effects is low, physicians need to be aware of their occurrence. Research progress of the prostacyclin class lOP-lowering medication side effects are reviewed.