How soon do STI symptoms appear after sex?

Every STI has a different incubation period. The incubation period is the time between the moment of infection and when symptoms first appear. Knowing the incubation period of different STIs is helpful when determining if the symptoms you may be experiencing are due to an STI or not. Many people wonder if symptoms of an STI can occur one or two days after having sex. In this article we will discuss how quickly symptoms of certain STIs can occur, what symptoms to watch out for, and when to get tested.

Table of Contents

• Common symptoms of STIs
• How quickly can STI symptoms appear?
• STI window periods
• STI incubation periods
• Getting tested for STIs
• Key takeaways

Common STI symptoms

Many STIs cause similar symptoms following an infection that signal something isn’t right (NHS, 2022). Common STI symptoms are:

• Itching in the vagina, penis or anus. 
• Blisters and sores
• Discharge that has changed in colour, quantity, or has an unpleasant smell
• Fever
• Burning or redness in the genital or throat area such as the tongue

If you are in doubt whether your symptoms are from an STI, getting tested is always a good idea. Homed-IQ’s STI Test Complete checks for 6 common STIs and can be done from home.

How quickly can symptoms of an STI appear?

Some STIs can cause symptoms in as little as 48 hours after infection. STIs that may cause symptoms within 48 hours of infection are genital herpes and gonorrhea. When you kiss or have sex with someone who has herpes, blisters on the mouth or genitals can appear two or more days after exposure. Similarly, gonorrhea can cause discharge from the penis or vagina within 48 hours of infection. While these STIs can cause symptoms in a minimum of 48 hours, sometimes they take longer, or will not appear at all. However, just because you do not experience symptoms within 48 hours does not mean you are not infected. The only way to be sure that you are uninfected is to wait until the window period is over to get tested. The window period is the time between when you are infected and when the infection will appear on an STI test. The window period for each STI is as follows:

STI Incubation Periods

As mentioned, the incubation period is the time between when you are infected with an STI and when symptoms appear. This is different from the window period, which is the time between when you are infected and when the infection will show up on a test. The incubation periods per STI are summarized in the table below:

Getting tested

Although STIs are nothing to be ashamed of, they still can make you feel anxious, worried, or unsure. If you have recently had unprotected sex or a previous partner advises you they have an STI, it’s a good decision to get tested. There are two different types of home STI tests; laboratory tests and rapid tests. Home STI tests with laboratory analysis have a number of advantages over rapid tests, such as a more reliable test result and the ability to test for a wider range of infections. For this reason, laboratory-certified home STI tests or getting tested at a clinic is advised over rapid tests from the drugstore.

STIs can cause a range of symptoms that take varying amounts of time to appear. While it is possible to experience symptoms of an STI within 48 hours, this is not very common. If you test for an STI before having symptoms or before the window period is over, the test result may not be reliable. That is why it is important to check the incubation and window periods of various STIs if you are experiencing symptoms before getting tested, and to wait until the window period is over if you are not experiencing symptoms yet.