**Abstract**

*Chlamydiae* are intracellular, gram-negative, and prokaryotic microorganisms. Capable of causing disease in many mammalian and avian species, there are three types that cause disease in humans: *Chlamydia trachomatis*, *Chlamydia pneumoniae*, and *Chlamydia psittaci*. Among the chlamydia species, *C. trachomatis* is the most studied and encountered type because it is a leading cause of trachoma and sexually transmitted diseases. *C. trachomatis*, a known pathogen of the genital tract, can also be routinely detected in the human gastrointestinal tract. It can infect the enteroendocrine cells of the gastrointestinal tract. The best-known manner for *C. trachomatis* to enter the gastrointestinal tract is through oral and anal sex. Most of them are dormant, without causing any infection in the infected person. Chlamydia proctitis is the most well-known disease caused by *C. trachomatis* in the gastrointestinal tract. In this section, we evaluated the often-overlooked *Chlamydia* and the gastrointestinal system findings within the gastroenterology practice, the diseases it causes, and the treatments for these diseases.

**Keywords:** chlamydia, gastrointestinal system, oropharyngitis, proctitis, Chlamydia trachomatis
