Sexual health
Medicines for Chlamydia
The most common bacterial sexually transmitted infection, often with no symptoms — easily treated with antibiotics, but able to cause serious problems if left undiagnosed.
Education and reference only. This explains which medicines are used and why, in plain language — it deliberately contains no doses and is not a substitute for advice from your doctor or pharmacist. Always discuss your own treatment with a qualified clinician, and check the BNF and the product labelling for prescribing detail.
Quick answer
What is Chlamydia?
Chlamydia is the most common bacterial sexually transmitted infection (STI) in the UK, especially in young sexually active people. It is passed on through unprotected vaginal, anal or oral sex, and from mother to baby during birth.
- How it is treated: Chlamydia is diagnosed with a simple test (a urine sample or a swab, which can often be done at home) and is easily treated with a course of antibiotics.
- Self-care: Using condoms, regular STI testing (especially under 25 and when changing partners), and ensuring partners are tested and treated all reduce chlamydia and its complications.
- When to seek help: Get tested at a sexual health clinic or via an online service if you are sexually active (even without symptoms), have symptoms, or a partner has an STI.
What it is
Chlamydia is the most common bacterial sexually transmitted infection (STI) in the UK, especially in young sexually active people. It is passed on through unprotected vaginal, anal or oral sex, and from mother to baby during birth. Most people have no symptoms, which is why it often goes unnoticed and why testing is so important. When symptoms do occur they can include unusual discharge, pain on passing urine, pelvic or testicular pain, and bleeding between periods or after sex. Left untreated, chlamydia can spread and cause complications such as pelvic inflammatory disease, which can affect fertility, and can also cause problems in pregnancy — so finding and treating it matters even without symptoms.
How it is treated
Chlamydia is diagnosed with a simple test (a urine sample or a swab, which can often be done at home) and is easily treated with a course of antibiotics. It is important that recent sexual partners are also tested and treated to prevent reinfection and onward spread, and that sex is avoided until treatment is complete (as advised). A repeat test may be recommended, particularly in younger people or during pregnancy. Testing is free and confidential at sexual health clinics and many other services, and regular testing is advised for sexually active young people and when changing partners. Using condoms reduces the risk of catching or passing it on.
For this condition, these medicines
Medicine classes used for Chlamydia
Each links to a full, dose-free guide — what it is, how it works, who can and cannot use it, side effects, interactions and FAQs.
Beyond medication
Lifestyle and self-care
Using condoms, regular STI testing (especially under 25 and when changing partners), and ensuring partners are tested and treated all reduce chlamydia and its complications. Testing is free and confidential.
When to get help
When to see a doctor
Get tested at a sexual health clinic or via an online service if you are sexually active (even without symptoms), have symptoms, or a partner has an STI. See a doctor for pelvic or testicular pain or fever, which may indicate a spreading infection.
Not sure how urgent it is? It is always OK to call NHS 111 for advice, day or night.
Answers
Chlamydia: frequently asked questions
Can you have chlamydia without symptoms?
Yes — most people with chlamydia have no symptoms, which is why regular testing is important. Untreated, it can still cause complications such as pelvic inflammatory disease and fertility problems.
How is chlamydia treated?
With a course of antibiotics. Recent partners should also be tested and treated to prevent reinfection, and sex avoided until treatment is complete. A repeat test is sometimes advised.
Keep reading
Related articles
Sources
Where this is drawn from
- NHS — Chlamydia
- BASHH — Chlamydia guidance
Related conditions
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