Chlamydia fact sheet

Chlamydia is a sexually transmissible infection. Many people who are infected do not have symptoms of infection but can still spread the disease. Chlamydia can lead to infertility, and other complications if not treated.​

Last updated: 20 December 2024

​​What is chlamydia?

Chlamydia is a common sexually transmissible infection (STI). It is caused by the bacteria Chlamydia trachomatis. Infection can occur in the throat, urethra (urine passage), cervix (opening of the uterus), rectum and eyes.

How does chlamydia spread?

​Chlamydia is spread by having vaginal, anal or oral sex without a condom or dental dam, and by sharing sex toys with someone who has the infection. Chlamydia can also be spread from mother to baby during childbirth.

Most people with a chlamydia infection have no symptoms and do not realise they have it. Even without symptoms, people can still pass the infection on to others.

Testing for chlamydia is easy, confidential and nothing to be ashamed about. It's important to get tested if you have had unprotected sex with a new or casual sexual partner.​

What are the symptoms of chlamydia?

Chlamydia usually has no signs or symptoms. If you do experience symptoms, they can occur 2 to 14 days after infection.

Symptoms can include:

  • unusual vaginal discharge
  • discharge from the penis
  • vaginal bleeding or spotting after sex or in between regular menstrual periods
  • pain or burning sensation while peeing
  • pain during or after sex 
  • pelvic pain
  • swollen and sore testicles
  • anal pain or discharge.
If left untreated, chlamydia can cause serious complications including:​
  • If you have a uterus (womb):
    • ​pelvic inflammatory disease or PID (when the womb and fallopian tubes become infected
    • pelvic adhesions (scars that cause  tissues within the pelvis to stick together) causing chronic pelvic pain
    • infertility (inability to become pregnant) due to damage to the womb or tubes by scar tissue
    • ectopic pregnancy (when the pregnancy develops in the fallopian tubes instead of in the uterus)
    • passing the infection to your baby during childbirth leading to conjunctivitis (eye inflammation) or pneumonia (lung infections)
  • ​epididymitis (inflammation of the tube from the testes)
  • swelling and tenderness of joints
  • conjunctivitis or eye inflammation
  • proctitis (inflammation of the rectum).​

Who is most at risk of chlamydia?

All sexually active people are at risk of infection. People who are most at risk of chlamydia are:

  • young people
  • people who have unprotected sex with someone who has chlamydia
  • people who have multiple sexual partners
  • anyone who has recently been diagnosed with any STI.

How do I protect myself from chlamydia?

Chlamydia infection can be prevented by:

  • consistently using condoms, dental dams, and water-based lubricant for vaginal, anal and oral sex
  • avoiding any sexual activity with someone diagnosed with chlamydia until 7 days after their treatment is finished and symptoms are fully resolved.

You can protect yourself from chlamydia complications by:

  • getting regular STI check-ups with your doctor
  • if you are pregnant, testing for all STIs during your antenatal check-ups to prevent passing on the infection to your baby during childbirth.

How is chlamydia diagnosed?

Chlamydia is an easily diagnosed and curable STI. Your doctor or nurse will either take a:

  • urine​ sample (peeing into a small jar)
  • swab test taken from the vagina, penis, urethra, anus, rectum or throat. These swabs can usually be self-collected and do not require you to be examined by your healthcare provider.

The urine or swab is then sent to a laboratory for testing. There are currently no reliable self-tests approved for use in Australia.

Even if you don't have symptoms, it is still important to have regular sexual health check-ups. More information about sexual health checks can be found at Sexual Health Check-up.

Call healthdirect​ (1800 022 222) to find a testing service near you.​

How is chlamydia treated?

Chlamydia is easily cured by a course of antibiotics. Treatment is doxycycline 100mg twice a day for 7 days. Another treatment is a single dose of azithromycin 1g. Your doctor will provide you with a prescription for the antibiotic.

It is important to see your healthcare provider to get treated. If your symptoms return or do not get better, go back to your doctor or nurse for help.

Chlamydia re-infection is common. Even after you've been successfully treated, you can still be re-infected if you have unprotected sex with someone who has chlamydia. It is important to have another test 3 months after being treated to make sure you have not been re-infected. 

What should I do if I test positive to chlamydia?

If you have chlamydia you should:

  • get treated right away
  • talk with your doctor or nurse which sexual partners you think may be at risk; your doctor or nurse can help you to contact them either personally or anonymously
  • inform all sexual partners from the last 6 months and don't have sex with these partners until they have been tested and treated if infected.

Further information

  • Sexual Health Infolink (SHIL) for free and confidential sexual health help including a confidential help line available from Monday to Friday 9am to 5:30pm on 1800 451 624.
  • Play Safe for young people to access information about safe sex and STI prevention, testing and treatment.
  • Let them know for advice and help with confidential and anonymous contact tracing for all sexual partners.
  • Better to Know for Aboriginal and Torres Strait Islander people to get information about STIs and where to get tested. The site also offers a way to tell sexual partners without them knowing who you are.
  • International Student Health Hub for international students to get information about safe sex, STIs, contraception and pregnancy.
  • Family Planning NSW Talkline for reproductive and sexual health information and advice. It is free, confidential and available Monday to Friday 8:00am-8:00pm on 1300 658 886.​
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