Although chlamydial infection is widespread, it can be prevented through proper precautions. Further, most patients with existing infections can be treated effectively.

How Can Infection Be Prevented?

There is a direct relationship between the number of sexual partners you have and your risk of developing chlamydia-or any STD. The most reliable way to prevent chlamydial infection is to:

  • abstain completely from sexual intercourse; or
  • have only one sexual partner who is uninfected and also sexually monogamous (reciprocal monogamy).

If your partner is infected, using a condom is a highly effective way of protecting yourself against infection-although not 100% protective.

How Should Chlamydia Be Treated?

Antibiotic therapy can effectively alleviate the symptoms and cure a chlamydia infection-as long as you take the medication as prescribed. As a general rule, treatment should begin as soon as possible after diagnosis, though there are exceptions. Medication may be started if your doctor suspects an infection that has not been confirmed through testing.

Antibiotic Options

For non-pregnant women, the CDC recommends the following medications:

  • azithromycin (Zithromax), 1 gram (gm) orally in a single dose; or
  • doxycycline (Vibramycin), 100 milligram (mg) orally, twice a day for seven days.

Azithromycin and doxycycline are equally effective. The primary advantage of azithromycin is that it is administered in a single dose. A seven-day course of doxycycline is less expensive than a single dose of azithromycin, but azithromycin's ease of use may outweigh its cost.

Other alternatives for treating chlamydial infection include:

  • erythromycin base (Ery-Tab, PCE), 500 mg, four times a day for seven days;
  • erythromycin ethylsuccinate (EES), 800 mg orally, four times a day for seven days; or
  • ofloxacin (Floxin), 300 mg, twice a day for seven days.

Erythromycin is less effective than azithromycin and doxycycline and may cause gastrointestinal side effects, which in turn leads many patients to stop taking the drug before the benefits have taken effect. Ofloxacin is as effective as azithromycin and doxycycline but is more expensive.

The CDC recommends that health care providers dispense medication for chlamydial infection on site and directly observe the patient taking the first dose. This is done to reduce the number of patients who do not comply with prescription guidelines.

Preventing Further Spread of Infection

To minimize the risk of transmitting chlamydia, you should abstain from sexual intercourse for seven days after beginning antibiotic treatment. You should also encourage your recent (within the past 60 days) sex partners to seek evaluation, testing, and possible treatment. In addition, you should abstain from intercourse until both you and your partner have completed treatment.

Concerns About Side Effects

Like all medications, antibiotics used to treat chlamydia can cause side effects. For example, antibiotic medications can alter the bacteria that normally inhabit the vagina or bowel and make a woman susceptible to vaginal yeast infections. Allergic reactions to the drugs that treat chlamydia have been reported but are relatively rare. In addition, some patients report side effects to specific drugs. Some drugs that can cause side effects are:

  • azithromycin-Although adverse reactions to single-dose azithromycin are rare, some women report gastrointestinal intolerance (diarrhea, nausea, vomiting, abdominal pain) and rash;
  • doxycycline-Side effects of doxycycline are more common and may include gastrointestinal intolerance, liver toxicity, esophageal ulcers, and photosensitive rashes;
  • erythromycin-As noted, gastrointestinal intolerance is a common side effect of erythromycin. Other, less frequently noted, side effects include mouth ulcers and hepatitis; and
  • ofloxacin-Occasional side effects to ofloxacin include gastrointestinal intolerance, headache, malaise, insomnia, restlessness, vertigo (dizziness), and liver toxicity.

Repeating Diagnostic Testing

If you are prescribed erythromycin to treat a chlamydial infection, three weeks after you finish taking the medication you will be re-tested. If your treatment includes azithromycin or doxycycline, re-testing is not necessary.

Is Treatment Different for Pregnant Women?

For treatment of chlamydia during pregnancy, the CDC recommends:

  • erythromycin base, 500 mg orally, four times a day for seven days; or
  • amoxicillin (Amoxil), 500 mg, three times a day for seven days.

Alternatives include:

  • erythromycin base 250 mg, four times a day for 14 days;
  • erythromycin ethylsuccinate 800 mg orally, four times a day for seven days; or
  • erythromycin ethylsuccinate 400 mg orally, four times a day for 14 days.

Because azithromycin is a relatively new drug and its safety and efficacy during pregnancy and lactation (breast-feeding) have not been firmly established, the CDC considers azithromycin to be second-line therapy during pregnancy. Nevertheless, because of its tolerability, high level of effectiveness, and simple dosing regimen, azithromycin is becoming increasingly popular for treatment of chlamydia infection in both pregnant and non-pregnant women.

Doxycycline and ofloxacin should not be used during pregnancy since they may interfere with fetal development. Doxycycline, for example, can discolor a baby's teeth, and fluoroquinolones-which include ofloxacin-inhibit DNA formation and may injure a baby's cartilaginous tissue.