What you need to know about chlamydia

Chlamydia is a sexually transmitted infection (STI) that is most easily passed on during sex without a condom. It can infect the genitals, rectum, throat and eyes. Chlamydia can be cured with antibiotics, and there are ways to reduce the chances of getting or passing on chlamydia, such as using a new condom correctly each time you have sex.

The words we use hereCATIE is committed to using language that is relevant to everyone. People use different terms to describe their bodies. This text uses medical terms, such as vagina and penis, to describe genitals.

Some people may use other terms, such as private parts or dick or front hole. CATIE acknowledges and respects that people use words that they are most comfortable with.

What is chlamydia?

Chlamydia is a sexually transmitted infection (STI). A person with chlamydia can pass it on to another person during sex. Chlamydia can infect the genitals, rectum, throat and eyes.

Most people with chlamydia have no symptoms, so they don’t know they have an infection. When symptoms do occur, they usually take two to three weeks to appear but it can take as long as six weeks.

Common symptoms vary depending on where the infection is.

Some common symptoms are:

  • Chlamydia in the genitals can cause an unusual fluid (“discharge”) to come out of the vagina or the penis, and pain when urinating (peeing).
  • Chlamydia in the rectum or anus can cause discharge or bleeding from the anus and pain in the anus.
  • Chlamydia in the throat or mouth can cause a sore throat.
  • Chlamydia in the eye can result in eye infections (conjunctivitis) causing itchy, swollen eyelids, bloodshot eyes (“pink eye”), and white, yellow or greenish discharge that may crust over the eye.

If it is not treated, chlamydia may lead to infertility, abdominal pain or pregnancy complications. Untreated infection of the eye can affect vision.

Am I at risk of getting chlamydia?

Anyone who is sexually active, including people who experience sexual violence, can get chlamydia. 

Chlamydia is most easily passed on during condomless, insertive vaginal or anal sex.

Chlamydia can also be passed on through condomless oral-penile contact (mouth on penis) oral-vaginal contact, oral-anal contact (rimming) and sharing of sex toys.

Chlamydia can be passed from a pregnant parent with chlamydia to a newborn during pregnancy or childbirth.

Chlamydia and HIV

Chlamydia can cause the amount of HIV in the genital and rectal fluids of a person with HIV to increase. This can increase the risk of sexual transmission of HIV. However, evidence shows that people living with HIV who are on effective HIV treatment do not pass on HIV sexually, even when they or their partners have an STI, including chlamydia.

What can I do?

Reduce your chances of getting chlamydia

Use a condom during insertive vaginal and anal sex.

Use a condom or oral dam during oral sex.

When sharing a sex toy, wash the sex toy and put a new condom on it between each use.

There is no vaccine to protect against chlamydia.

HIV PrEP does not prevent the transmission of chlamydia.

Get tested

The only way to know for sure whether or not you have chlamydia is to get tested. You should get tested if you experience symptoms of chlamydia or if you have a current or recent sex partner diagnosed with chlamydia.

Consider getting tested if you:

  • have condomless oral, anal or vaginal sex
  • have had multiple sex partners within the last 12 months
  • have had sex with someone from, or who has visited, an area where chlamydia is common
  • have, or have had, another STI
  • are pregnant or planning to become pregnant

A healthcare provider can do the test. The test involves a swab of the genitals, rectum or throat or a urine (pee) sample. Tell the healthcare provider about all the different kinds of sex you are having so they can test all the right parts of your body.

It is a good idea to get tested for other STIs, including HIV, when you get tested for chlamydia. Other STIs can be passed on in the same way as chlamydia. Talk to your healthcare provider about how often you should get tested for chlamydia and other STIs.

If you are diagnosed with chlamydia, a healthcare provider will talk to you about informing your sex partners that they might have been exposed to chlamydia and encouraging them to get tested. If you aren’t comfortable or able to notify your sex partners, a healthcare provider will contact them, and your identity will not be revealed.

Get treated

Chlamydia can be cured with a single dose or a short course of antibiotics. If you are given a single dose to treat the infection, you should wait for seven days after taking it before having sex again. If you are given pills to take for seven days, you should wait until you have taken all the pills before having sex again. If you have a regular partner or partners, they should also be treated before you have sex with them.

After you are cured of one chlamydia infection, you cannot pass it on to someone else. But you can get another chlamydia infection in the future, and pass this on.


This information sheet was developed in partnership with the Sex Information and Education Council of Canada (SIECCAN).


Chlamydia CATIE fact sheet