Chlamydia - FAQs

A blog post by Dr. Christian Jessen, posted on the 1st of May.

Chlamydia - Frequently Asked Questions

Having worked as a sexual health doctor for many years I have noticed that people ask certain questions substantially more than others. So I thought I would answer some of them here.

Many people ask, quite sensibly, whether having caught chlamydia once, they are protected from it in the future. Whilst this does happen with certain infections like chicken pox and measles it is sadly not the case with chlamydia. Just because you have been successfully treated in the past does not mean that you are protected from becoming infected with Chlamydia again in the future. With some infections, our body develops a strong immunity if we’ve been exposed to a particular bug, but this does not seem to happen with an infection like chlamydia and people can keep catching it repeatedly if they have unprotected sex with another infected person. In fact, future infections can cause a far greater immune response with more symptoms and more tissue damage than the very first infection. If you have previously been treated for it, it may be a good idea to do a repeat test after three months, just to make sure you have not been re-infected.

Another common question is whether you need to have a test to check that the chlamydia has gone after treatment. Generally speaking if you took the treatment exactly as instructed you would not normally need a follow-up test. However, you ought to repeat the test if you think you may have come into contact with chlamydia again, if you had unprotected sex with a partner before the treatment was finished, if you did not complete the treatment or did not take it according to the instructions, and if the signs and symptoms don’t go away. You may need to have a second dose of antibiotics to clear it up properly.

Many people are keen to know how soon after treatment for chlamydia they can have sex again. I tend to advise them not to have oral, vaginal or anal sex, or use sex toys, until seven days after you and your partner have both finished the treatment and any symptoms that you may have been experiencing have gone. This is to help prevent you being re-infected or passing the infection on to someone else. If you have been given a single does treatment consisting of 1g of an antibiotic called azithromycin, then you will need to avoid sex for seven days after you have taken the tablets.

Remember that in many cases chlamydia causes no symptoms and so you may have no idea that you are infected. You can only be certain you have Chlamydia if you have a Chlamydia test so don’t delay in getting a check-up.


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