Examples
| Brand Name | Chemical Name |
| Amoxil, Trimox | amoxicillin |
| Zithromax | azithromycin |
| Doryx, Vibramycin, Vibra-Tabs | doxycycline |
| E-Base, Erythrocin | erythromycin |
| E.E.S. 400, EryPed | erythromycin ethylsuccinate |
| Levaquin | levofloxacin |
| Floxin | ofloxacin |
Why It Is Used
Antibiotics are given to:
- People who have positive chlamydia tests.
- Sex partners within the last 60 days of people diagnosed with chlamydia—even if they do not have symptoms.
- Newborns of women who have chlamydia at the time of delivery.
All of these medicines are prescribed for men and for women who are not pregnant. Pregnant women can take only erythromycin, amoxicillin, and azithromycin. Only erythromycin is given to babies.
How Well It Works
Antibiotic treatment, if taken exactly as directed, normally cures chlamydia infections. If antibiotics are not taken properly, the infection will not be cured.
Antibiotic recommendations1
The U.S. Centers for Disease Control and Prevention recommends the following:
| Medicine dose | Days of treatment |
|---|---|
|
Azithromycin 1 g orally |
1 day |
|
Doxycycline 100 mg orally twice a day |
7 days |
| Alternative medicine dose | Days of treatment |
|---|---|
|
Erythromycin 500 mg orally 4 times a day |
7 days |
|
Erythromycin ethylsuccinate 800 mg orally 4 times a day |
7 days |
|
Ofloxacin 300 mg orally twice a day |
7 days |
|
Levofloxacin 500 mg orally |
7 days |
Azithromycin and doxycycline are both good for treating chlamydia. Some people may not be able to take these medicines but are able to take an alternative. Erythromycin treatments do not work as well as the other recommended antibiotics.
People who are also infected with HIV receive the same medicine as those without HIV.
Antibiotics recommended in pregnant women1
The U.S. Centers for Disease Control and Prevention recommends the following:
| Medicine dose | Days of treatment |
|---|---|
|
Azithromycin 1 g orally |
1 day |
|
Amoxicillin 500 mg orally 3 times a day |
7 days |
Erythromycin and amoxicillin are both used to treat chlamydia, though some pregnant women may have fewer side effects with amoxicillin.2
| Alternative medicine dose | Days of treatment |
|---|---|
|
Erythromycin 250 mg orally 4 times a day |
14 days |
|
Erythromycin ethylsuccinate 800 mg orally 4 times a day |
7 days |
|
Erythromycin ethylsuccinate 400 mg orally 4 times a day |
14 days |
|
Erythromycin 500 mg orally 4 times a day |
7 days |
For pregnant women, testing is recommended 3 weeks after treatment. This is done to prevent complications from an infection that has not been cured.1
Side Effects
The most common side effects of these medicines are nausea and vomiting. Taking azithromycin after eating may reduce nausea.
Doxycycline causes less nausea and vomiting but may cause yeast infections in women.
If side effects occur and cannot be controlled, contact your health professional. Other antibiotics may be prescribed that cause fewer side effects.
A large study indicates that people who take erythromycin along with certain common medicines may increase their risk of sudden cardiac death.3 The study showed that the risk of sudden cardiac death is greater when erythromycin is taken with some medicines that inhibit certain liver enzymes—such as certain calcium channel blockers, certain antifungal medicines, and some antidepressants—than when these medicines are not taken together.
See Drug Reference for a full list of side effects. (Drug Reference is not available in all systems.)
What To Think About
To be effective, antibiotics need to be taken as directed. If doses are missed or treatment is not completed, the chlamydia infection may not be cured.
The advantage of azithromycin is that it is taken in one dose. Because it is easy to take as prescribed, this medicine may help reduce the risk of spreading chlamydia.
Do not have sex while you are being treated for an STD. People taking a single dose of azithromycin should not have sex for 7 days after treatment.
Call your health professional if symptoms continue or new symptoms develop 3 to 4 weeks after treatment.
Repeated chlamydia infections increase the risk of pelvic inflammatory disease (PID). Some health professionals may recommend retesting 3 to 12 months after treatment to reduce the risk of complications from reinfection.1
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References
Citations
Centers for Disease Control and Prevention (2006). Sexually transmitted diseases treatment guidelines 2006. MMWR, 55(RR-11): 38–42.
Brocklehurst P, Rooney G (2006). Interventions for treating genital chlamydia trachomatis infection in pregnancy. Cochrane Database of Systematic Reviews (3). Oxford: Update Software.
Ray WA, et al. (2004). Oral erythromycin and the risk of sudden death from cardiac causes. New England Journal of Medicine, 351(11): 1089–1096.
Credits
| Author | Sabra L. Katz-Wise |
| Author | Ralph Poore |
| Editor | Susan Van Houten, RN, BSN, MBA |
| Associate Editor | Denele Ivins |
| Associate Editor | Pat Truman |
| Primary Medical Reviewer | Renée M. Crichlow, MD - Family Medicine |
| Primary Medical Reviewer | Kathleen Romito, MD - Family Medicine |
| Specialist Medical Reviewer | Jeanne Marrazzo, MD, MPH - Infectious Disease |
| Last Updated | January 18, 2007 |
Ralph Poore
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