Topical prostaglandin analogs (PGAs) may cause gastrointestinal adverse effects.
Study 1
Cai et al. 2013, performed a molecular genetic analysis on the patient reported by Yu et al., who developed nausea, vomiting and diarrhea after topical application of travoprost and latanoprost, but not bimatoprost, and then speculated that the mechanism underlying the gastro-intestinal distress secondary to PGA topical application should be attributed to their stimulation of smooth muscles of the gastric and intestinal tract via prostanoid receptors. To further verificate the speculation, other three glaucoma patients who exhibited different gastro-intestinal responses to different PGA medications were enrolled.
The results suggested that the relative expression level of FP receptor, versus EP receptors, might be associated with the severity of gastro-intestinal effects incurred by PGAs. Owing to the differed expression levels of FP receptor, the responses of various patients to different PGAs can be variable «Cai S, Zhou X, Yan N ym. Possible mechanism for th...»1.
Study 2 (case report) «Yu M, Chen X, Jia ym. Travoprost and latanoprost, ...»2
Study 3
Three cases with proven gatrointestinal disturbances due to latanoprost have been described. All these three patients had severe gastrointestinal adverse effects after initiating treatment with prostagalndin analogues; fisrt patient developed esophageal spasm, regurgitation, constipation, and generalized malaise. The second patient noted a burning sensation in his stomach, heartburn, and an acid aftertaste. The third patient developed nausea, vomiting, and dizziness. The adverse effects in all 3 patients were confirmed with unmasked challenge-rechallenge tests, and all the patients were given at least 2 additional prostaglandin analogues «Papachristou GC, Ritch R, Liebmann JM. Gastrointes...»3.