Chlamydia

What you need to know

Chlamydia is the most common bacterial sexually transmitted infection. Below are some key facts:
  • It affects both men and women.
  • About 1 in 10 sexually active young people who are tested have Chlamydia.
  • You can get Chlamydia by having sex (vaginal, anal, and oral, or by sharing sex toys) with someone who has the infection.
  • An infection can be recent or you could have had it for many months, even years without knowing, as 70% of people with Chlamydia do not know they are infected meaning they have no symptoms
  • Chlamydia can also be passed to the eyes if infected genital body fluid (vaginal discharge or semen) gets into them.

Signs and symptoms

More than two in three women and one in two men with chlamydia won’t have any obvious signs or symptoms, or will have symptoms so mild they’re not noticed.

Signs and symptoms can show up 1–3 weeks after coming into contact with chlamydia, many months later, or not until the infection spreads to other parts of your body.

You might notice:

male symbol

Men

  • A white/cloudy or watery discharge from the tip of the penis
  • Pain and/or burning when passing urine
  • Painful swelling of the testicles
  • Irritation at the tip of the penis
female symbol

Women

  • Bleeding between periods and/or heavier periods (including women who are using hormonal contraception)
  • Bleeding after sex
  • Lower abdominal pain (pelvic pain)
  • An unusual vaginal discharge
male and female

Men and Women

There are rarely any symptoms if the infection is in the rectum (back passage) but it may cause discomfort and discharge. Infection in the eyes can cause pain, swelling, irritation and/or discharge. Infection in the throat is uncommon and usually has no symptoms.

Testing and treatment

Chlamydia tests are carried out by taking swabs from the penis, vagina, anus or throat. A urine sample can also be used with men. The sexual health clinic will recommend the best test for you depending on whether you have any symptoms, what they are and the type of sex you have.

Chlamydia can be treated with antibiotics and it is important that you complete the course. If you are treated for chlamydia, it is really important that your partner also gets treated before you have sex again to prevent reinfection.

If you visit a clinic, staff will explain your treatment and how to avoid further infections in the future. Do tell a member of staff if you think you maybe pregnant as this may affect the type of antibiotic given. Remember, using condoms every time you have vaginal, anal or oral sex will significantly reduce the risk of getting or passing on STIs including chlamydia. Condoms can be used for different types of sex (anal, oral and vaginal).

Find out more about self-testing and order a postal kit

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