What You Need to Know About Azithromycin for Chlamydia Treatment

By Jenell Decker, MD
Medically reviewed checkmarkMedically reviewed
October 11, 2021

Chlamydia is one of the most common sexually transmitted diseases (STDs) in America.

In fact, in 2018, four million infections occurred in the U.S. However, many cases may go unreported because people with chlamydia are often asymptomatic and therefore don’t know they have an infection. 

Because chlamydia can go undetected, regular testing is extremely important in both fighting the spread of the infection and in treating it.

If you happen to test positive, the good news is, the vast majority of chlamydia cases can be cured easily with antibiotics such as azithromycin.

In this article, I’ll explain if azithromycin (Zithromax) treats chlamydia, who can take this antibiotic, the best dosage to treat chlamydia, and how to take it.

Then I’ll break down how azithromycin compares with another antibiotic, doxycycline, for treating chlamydia.

Finally, I’ll share everything you need to know about being tested for chlamydia.

Does Azithromycin Work for Chlamydia?

Azithromycin works to treat genital chlamydia in both men and women by stopping the bacteria from multiplying.

Studies suggest that a one-gram dosage has 97% efficacy.

That means that for every 100 people who take azithromycin to treat chlamydia, 97 will be cured and three will not be cured.

In order to effectively treat chlamydial infections, azithromycin should be taken as prescribed  and until the dosage is completed.

Ending the medication early increases the chance that the bacteria will not be completely killed off.

Who Can Take Azithromycin?

Adults and adolescents of 10-19 years of age can take azithromycin to treat genital chlamydia.

However, if you are allergic to azithromycin, pregnant, or breastfeeding, your doctor may prescribe different antibiotics, such as amoxicillin or erythromycin.

What Dosage Treats Chlamydia? 

For people with uncomplicated genital chlamydia, the Centers for Disease Control and Prevention (CDC) recommends a single dose of azithromycin (1 gram) taken orally to cure the infection. 

Azithromycin comes in three forms: 

  • Tablet
  • Extended-release (long-acting) powder
  • Regular-release powder

For both powder formulas, either you or a pharmacist mix it with liquid to take. 

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Taking Azithromycin

Always follow the directions from your doctor or pharmacist for taking azithromycin. 

Azithromycin is taken as a single dose, one time.

It should be taken as soon as you receive the prescription. Azithromycin can be taken with or without food, however, the extended-release form is typically taken on an empty stomach. 

If you take the liquid (suspension) form, shake it well before using and use a dosing spoon to measure an accurate dose. If you are prescribed the powder, mix it with water according to directions.

How long does it take?

It takes about one week for azithromycin to completely cure a chlamydial infection, and in some cases it can take up to two weeks for the infection to clear.

If you are sexually active during this time, you can pass the infection to your partner(s), even if you have no symptoms. For these reasons, you should avoid having sex of any kind (intercourse, oral, or anal sex) during treatment. 

Can you drink alcohol while taking it?

While it’s never a good idea to mix any prescription medication with alcohol, there are no known interactions between azithromycin and alcohol.

Moderate consumption of alcohol (one drink for women and two drinks for men per day) should not reduce the effectiveness of the drug or cause any unwanted side effects.

Side effects

While few people experience any issues, most of the well-known side effects of azithromycin are not serious.

These include: 

A 2012 study found that azithromycin could increase the risk for cardiovascular death due to arrhythmias (irregular heart beats).

This prompted the U.S. Food and Drug Administration (FDA) to issue an official safety announcement in 2013.

You should not take azithromycin if any of the following are true:

  • You are a woman experiencing lower belly pain, pain during sex, vomiting, or fever.
  • You are a man experiencing pain or swelling in the testicles or fever.
  • You have had an allergic reaction after taking azithromycin or other antibiotics. 
  • You have a serious long-term illness, such as kidney, heart, or liver disease.
  • You are currently taking another prescription medication, including medicine for diabetes. In this case, consult your pharmacist to discuss possible drug interactions.

While rare, an allergic reaction could also occur. If you experience any of the symptoms below while taking azithromycin, seek medical attention right away: 

  • Difficulty breathing or tightness in the chest
  • Closing of the throat
  • Swelling of the lips or tongue
  • Rash 

Azithromycin vs Doxycycline for Chlamydia

Azithromycin and doxycycline are the most commonly prescribed drugs to treat chlamydia.

While azithromycin is prescribed in a single, one-gram dose taken orally, doxycycline is typically prescribed in a 100-milligram (mg) dose taken orally twice a day for seven days. 

A 2014 meta analysis of 23 studies found that doxycycline had a slightly higher efficacy (up to 3% higher) compared with azithromycin.

However, other research suggests that treatment with a single oral dose of azithromycin appears to be as safe and efficacious as a seven-day course of doxycycline for the treatment of uncomplicated genital chlamydial infection.

Talk to your healthcare provider about which medication is best for you.

Testing Information

Whether or not you were exposed to chlamydia or think you may have been, the CDC recommends annual screenings for:

  • Sexually active women younger than 25
  • Women 25 and older with new or multiple sexual partners
  • Women 25 and older whose sexual partner has a sexually transmitted infection (STI)
  • Sexually active men who have sex with men 
  • People who are HIV positive

Many different providers—including family planning centers, private doctors’ offices, sexual health clinics, hospital clinics, and health departments—typically provide testing for chlamydia and other STDs, so explore your options and pick what is most comfortable and convenient for you.

The actual test is simple. The healthcare provider will perform one of the following:

  • Swab test: They use a cotton round or stick to take a sample of tissue or fluid from the vagina or cervix for women or from the urethra for men.
  • Urine test: You pee in a cup to collect a urine sample that is sent to a lab to be tested.

You can expect results in about 2-5 days depending on the type of test and where it’s done.

How K Health Can Help

Did you know you can access online urgent care with K Health?

Check your symptoms, explore conditions and treatments, and if needed, text with a healthcare provider in minutes. 

K Health’s AI-powered app is based on 20 years of clinical data.

Frequently Asked Questions

Can you get chlamydia more than once?
Yes, even after successful treatment, you can get chlamydia more than once. This happens either through sexual activity with an infected partner or if you do not take your prescribed medication properly, causing the infection to remain in your body.
Can chlamydia go untreated?
Untreated chlamydia can lead to serious health problems with both short- and long-term consequences. These include swelling in the reproductive organs, fertility issues, and, in women, pelvic inflammatory disease (PID).

K Health articles are all written and reviewed by MDs, PhDs, NPs, or PharmDs and are for informational purposes only. This information does not constitute and should not be relied on for professional medical advice. Always talk to your doctor about the risks and benefits of any treatment.

Jenell Decker, MD

Dr. Decker is a family medicine physician who completed her residency at East Carolina University School of Medicine. She graduated medical school from Marshall University School of Medicine.