Health Knowledge Hub
Can you have an STI without knowing?
Yes. Several common STIs often cause no noticeable symptoms, which is why testing matters even when you feel well.
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Why some STIs go unnoticed
The NHS notes that many people with chlamydia and gonorrhoea do not notice any symptoms. Syphilis and HIV can also go through stages where there are few or no signs, or where symptoms are mild and easily mistaken for something else.
Feeling well is therefore not a reliable way to know whether you have an infection. An infection can still be passed on to partners, and some untreated infections can cause longer-term health problems.
What symptoms can look like
When symptoms do appear they can include unusual discharge, pain when urinating, sores, rashes, or flu-like illness. These signs are not specific to one infection, so they cannot tell you which STI, if any, you have.
If you have symptoms, the NHS recommends getting checked at a sexual health clinic or by a GP rather than relying on a home screening test alone.
How testing fits in
Testing is the only way to know your status. You can test through NHS sexual health services, and home screening kits can be one convenient option for people without symptoms. Any positive or unclear home result should be confirmed by a healthcare professional.
Related on CareFree Kits
Sources
- NHS – Sexually transmitted infections (STIs) (nhs.uk/conditions/sexually-transmitted-infections)
- NHS – Chlamydia (nhs.uk/conditions/chlamydia)
- NHS – Gonorrhoea (nhs.uk/conditions/gonorrhoea)
Last reviewed 5 November 2026. This guide has not been clinically reviewed by a named professional.