Written by Dr Claudia Pastides, 11th March 2019

Chlamydia is a common sexually transmitted infection. Studies have estimated that between 1.5% and 10% of people aged 15-24 will have chlamydia. This easily treated infection often has no symptoms, so it is important to have a sexual health screen if you could be at risk of chlamydia.


Caused by bacteria, chlamydia is spread through vaginal, oral and anal sex.

Risk factors

You are more likely to get chlamydia if you:

  • Are sexually active
  • Have multiple sexual partners
  • Have sexual intercourse without a condom
  • Are of younger age (under 25)
  • You have a history of prior sexually transmitted infections

Typical symptoms

  • Most people with chlamydia do not have symptoms, so it is important to get screened for this infection
  • Increased urination
  • Painful urination
  • Penile discharge
  • Testicular pain or swelling
  • Pain with ejaculation

Common treatment

  • Antibiotics

When to speak to a doctor

Chlamydia is best tested for and treated at a sexual health clinic. It is recommended that you are also tested for other sexually transmitted infections at the same time. To find your local NHS sexual health clinic, go to here

It is important to speak to a doctor if you have:

  • Symptoms that do not resolve despite antibiotic treatment
  • Recurring symptoms
  • Abdominal pain
  • Pelvic pain
  • Fever


  • Always using a condom
  • Getting regular screenings
  • Asking your partner to be tested for sexually transmitted infections
  • Avoiding intercourse until treatment has been completed

More information

British Association for Sexual Health and HIV