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Medical Author:

Melissa Conrad Stöppler, MD

Melissa Conrad Stöppler, MD

Melissa Conrad Stöppler, MD, is a U.S. board-certified Anatomic Pathologist with subspecialty training in the fields of Experimental and Molecular Pathology. Dr. Stöppler's educational background includes a BA with Highest Distinction from the University of Virginia and an MD from the University of North Carolina. She completed residency training in Anatomic Pathology at Georgetown University followed by subspecialty fellowship training in molecular diagnostics and experimental pathology.

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Medical Editor:

William C. Shiel Jr., MD, FACP, FACR

William C. Shiel Jr., MD, FACP, FACR

Dr. Shiel received a Bachelor of Science degree with honors from the University of Notre Dame. There he was involved in research in radiation biology and received the Huisking Scholarship. After graduating from St. Louis University School of Medicine, he completed his Internal Medicine residency and Rheumatology fellowship at the University of California, Irvine. He is board-certified in Internal Medicine and Rheumatology.

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In this Article

• Sexually transmitted diseases (STDs) in men facts
• What are STDs and how can their spread be prevented?
• Diseases associated with genital lesions
• Chancroid
• Genital herpes
• Lymphogranuloma venereum (LGV)
• Syphilis
• Human papillomavirus (HPV)
• Diseases associated with urethritis
• Urethritis
• Chlamydia
• Gonorrhea
• Systemic STDs
• Human immunodeficiency virus (HIV)
• Hepatitis B
• Hepatitis C
• Human herpes virus 8 (HHV-8)
• Ectoparasitic infections
• Sexually Transmitted Diseases (STDs) FAQs
• Find a local Urologist in your town
• Sexually Transmitted Diseases (STDs in Men) Index

Chlamydia is an infection caused by the bacterium Chlamydia trachomatis that most often occurs in sexually active adolescents and young adults. It can cause urethritis and the resultant complicating infections of epididymitis and orchitis. Recent studies have proven, however, that both infected men and infected women commonly lack symptoms of chlamydia infection. Thus, these individuals can unknowingly spread the infection to others. Consequently, sexually active individuals should be routinely evaluated for chlamydial urethritis. Note that another strain (type) of Chlamydia trachomatis, which can be distinguished in specialized laboratories, causes LGV (see above).

A convenient single dose therapy for chlamydia is oral azithromycin (Zithromax). Alternative treatments are often used, however, because of the high cost of this medication. The most common alternative treatment is doxycycline. Patients should abstain from sex for 7 days after the start of treatment and to notify all of their sexual contacts. People with chlamydia are often infected with other STDs and therefore should undergo testing for other infections that may be present at the same time. Their sexual contacts should also then be evaluated for chlamydial infection.

The most common reason for the recurrence of chlamydia infection is the failure of the partners of infected persons to receive treatment. The originally infected person then becomes reinfected from the untreated partner. Other reasons are the failure to correctly follow one of the 7-day treatment regimens or the use of erythromycin for treatment, which has been shown to be somewhat less effective than azithromycin or doxycycline. Complicated chlamydial infections, epididymitis, and orchitis are generally treated with a standard single-dose therapy as used for Neisseria gonorrhoeae (described below) and 10 days of treatment for Chlamydia trachomatis with doxycycline. In this situation, a single dose therapy for chlamydia is not an option.

What should a person do if exposed to someone with Chlamydia?

Persons who know that they have been exposed to someone with chlamydia should be evaluated for the symptoms of urethritis and tested for evidence of inflammation and infection. If infected, they should be treated appropriately. Many doctors recommend treating all individuals exposed to an infected person if the exposure was within the 60 days preceding the partner's diagnosis.