Chlamydia is treated with antibiotics, and the standard treatment is doxycycline taken twice a day for seven days. It’s one of the most curable sexually transmitted infections, and most people clear the infection completely with a single course of medication. Here’s what to expect from treatment and what you need to know to make sure it works.
The Standard Treatment
Doxycycline 100 mg twice daily for seven days is the first-line treatment for chlamydia in most adults. You take one pill in the morning and one in the evening, and the full week of treatment is important even if symptoms clear up sooner. Stopping early can leave bacteria behind and allow the infection to come back.
A newer delayed-release formulation of doxycycline lets you take a single 200 mg tablet once a day for seven days instead. It works just as well as the twice-daily version and tends to cause fewer stomach issues, though it costs more.
Azithromycin used to be the go-to option because it was a single dose, making it easy to complete. However, doxycycline has moved ahead as the preferred choice because it’s proven more reliable, particularly for rectal chlamydia infections, which are common and often go undiagnosed. Azithromycin may still be used as an alternative when doxycycline isn’t an option.
If You Can’t Take Doxycycline
Some people have allergies or other reasons they can’t use doxycycline. In those cases, alternatives include azithromycin or levofloxacin, which is taken once daily for seven days. Your provider will choose based on your specific situation, including whether you’re pregnant, breastfeeding, or have drug sensitivities.
Erythromycin, an older antibiotic that was once commonly prescribed for chlamydia, is no longer recommended. It caused frequent stomach problems that made people stop taking it before finishing the course, which defeated the purpose.
Treatment During Pregnancy
Doxycycline is not safe during pregnancy because it can affect fetal bone and tooth development. Pregnant individuals are typically treated with azithromycin or amoxicillin instead. If you’re pregnant and diagnosed with chlamydia, your provider will select an antibiotic that’s safe for both you and the baby, and you’ll likely be retested after treatment to confirm the infection is fully cleared.
Common Side Effects
The most frequent complaint with doxycycline is stomach upset: nausea, cramping, or diarrhea. Taking it with food and a full glass of water helps. Avoid lying down for at least 30 minutes after swallowing the pill, because doxycycline can irritate the esophagus if it doesn’t make it all the way to your stomach. You should also avoid prolonged sun exposure during treatment, as doxycycline can make your skin more sensitive to sunburn.
Dairy products and antacids can interfere with how well your body absorbs doxycycline, so separate those by at least two hours.
What to Do While You’re Being Treated
You need to avoid sex for seven days after starting treatment (or seven days after a single-dose antibiotic, if that’s what you were prescribed). This means all sexual contact, including oral sex, not just intercourse. Having sex too soon risks passing the infection to a partner or getting reinfected yourself.
Your sexual partners need treatment too. Anyone you’ve had sex with in the past 60 days should be tested and treated, even if they have no symptoms. Most people with chlamydia don’t have symptoms, which is exactly how it spreads so easily.
Getting Your Partner Treated
Expedited partner therapy (EPT) is an option in many states that lets your healthcare provider write a prescription for your partner without examining them first. You pick up the medication and bring it to your partner directly. The CDC considers EPT a useful tool, especially for treating male partners of women diagnosed with chlamydia. The legal status of EPT varies by state, so your provider can tell you whether it’s available where you live.
EPT exists because, realistically, not every partner will go to a clinic on their own. Untreated partners are the most common reason people end up with chlamydia again shortly after completing their own treatment.
Follow-Up Testing
For most people, a routine “test of cure” isn’t necessary after completing doxycycline, because the treatment is highly effective. However, retesting is recommended about three months after treatment to check for reinfection, since reinfection rates are high. This isn’t checking whether the antibiotics worked; it’s checking whether you’ve been exposed again.
If you’re pregnant, follow-up testing to confirm the infection is gone is standard, typically about four weeks after finishing treatment. Untreated chlamydia during pregnancy can lead to complications including preterm birth and transmission to the baby during delivery.
What Happens If Chlamydia Goes Untreated
Chlamydia responds well to antibiotics, but left untreated it can cause serious problems. In women, the infection can spread to the uterus and fallopian tubes, causing pelvic inflammatory disease, which can lead to chronic pain and fertility problems. In men, untreated chlamydia can cause painful inflammation of the reproductive tract. For all genders, having chlamydia also increases susceptibility to other STIs, including HIV.
The good news is that treatment is straightforward, inexpensive, and widely available. A week of antibiotics is all it takes to clear the infection completely in the vast majority of cases.