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"If I have chlamydia and took two 500mg Azithromycin tablets three hours apart, will it be effective?"

ZocdocAnswersIf I have chlamydia and took two 500mg Azithromycin tablets three hours apart, will it be effective?


I was prescribed azithromycin before knowing I had tested positive for chlamydia. I was unaware that I should take the two 500mg tablets at the same time, and took one around 9am. My doctor called and told me my results and how to take the medicine and I took the second pill around 11:30am. Will this be effective or will I have to get another dose?


This is an important question to discuss with your primary care doctor. Generally speaking, Azithromycin is a very long acting antibiotic. In other words, when you take it the drug can stay around in your body for longer than a day. Thus, taking the second pill 3 hours later probably had no effect on its efficacy. If you had taken the second one the next day, it might not have reached peak therapeutic doses. However, 3 hours is likely an insignificant amount of time. The one way to make sure is to return to your doctor in a month or so and get re-tested. My other concern in someone that was treated for Chlamydia is whether or not they were also simultaneously treated for gonorrhea. We almost always treated them together because many patients that test positive for one also have the other. The most common treatment for gonorrhea is a single injection of the antibiotic Ceftriaxone. I wonder if you doctor also gave this to you as it is common practice to do so. I suggest that you schedule an appointment with your primary care doctor. The two of you can discuss if re-testing for Chlamydia is necessary. In addition, you should make sure that you were test for and treated for gonorrhea as well. Remember that you can prevent this from occurring again by using condoms every time you have sex. Good luck.

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