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How long will 500mg of zithromax stay in your system?

Customer Question

How long will 500mg of zithromax stay in your system?
Submitted: 1 year ago.
Category: Medical
Expert:  Dr. Thomas, MD replied 1 year ago.

Hello and welcome!

I am Dr. Thomas, board certified in internal medicine and integrative medicine and I can certainly help you with this.

I'll either give you an answer or ask for some information; either way, make sure you use reply/reply to expert as needed until we are done before you rate the interaction.

Zithromax is an antibiotic with a particularly long half life.....which means it stays in your system longer than the average antibiotic.

IN fact, after your last pill, it will clear out in about 150 hours from that point.

This is why it can be used effectively with only 5 days of use, or even 3 days of use [the 3 pak], for certain infections.

The 5 pak is in fact adequate for treating pneumonia because of the long half life.

Let me know if you have further questions.

Please select a 4 or 5 rating as this is how we are paid. Great service is my goal and if you are not yet satisfied please reply to me via the REPLY TO EXPERT button. I will be happy to continue further and do everything I can to provide you with the service you seek.

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Customer: replied 1 year ago.
I only need to know how long 2 pills 250mg each (1st dose) will stay in a persons system
Customer: replied 1 year ago.
Relist: Answer quality.
I only want to know how long the first dose of zithromax 250mg x2 pills will stay in my system.
Customer: replied 1 year ago.
Relist: Inaccurate answer.
I want to know how long the first dose 250mg x2 pills of zithromax will stay in my system.
Customer: replied 1 year ago.
Relist: Inaccurate answer.
I would like my question answered adequately
Expert:  Dr. David replied 1 year ago.
Hello, this is Dr. David. I have read your question and am ready to help.

I would like to disagree with the above expert.

zithromax has a half life if 68 hours.

so after 5 half lives, there is only 3% of the drug left in your system.
after 6 half lives, there is only 1.5% of the drug left in your system

6 half lives would be 408 hours.

so the answer is that it will take more than 400 hours for the zithromax to pretty much be completely out of your system. 408 hours is 17 days.
Customer: replied 1 year ago.
I just want to know how long 500mg of zithromax (2 pills) will stay in a human's system! Not the entire dose just 2 pills. Please explain in hours, how long 2 pills of zithromax equaling 500mg will stay in your system! I highly doubt it is 17 days.
Expert:  Dr. David replied 1 year ago.
the data that I gave you is for two pills.

the primary excretion (or how the body gets rid of azithromycin) from your body is through the bile system.

there is extensive uptake of azithromycin in your tissues and then it is slowly released from your tissues. that is why it takes 68 hours for the amount in your body to be cut in half . and then it takes another 68 hours for amount in your body to be cut in half again.

so after 136 hours, you have a quarter of the dose left in your body.
after 204 hours, you have an eighth (1/8 or 0.125) of the dose left in your body
after 272 hours, you have a 1/16 or 0.0625 of the dose left in your body
after 340 hours, you have 1/32 or 0.03125 of the dose left in your body
after 408 hours, you have 1/64 or 0.015625 of the dose left in your body
Customer: replied 1 year ago.
I was just made aware of a study that zithromax can cause heart issues serious ones and I do have benign PVC's I have taken zpacks many many times in the past but now that I am aware log this study I will never again. That is why I wanted to know how long the first dose can be expected to leave my body or when I am in a safe zone. I took the first dose this morning at 7:30. If something was to happen would it have happened? When us the highest concentration and when r u in the safe zone?
Expert:  Dr. David replied 1 year ago.
you are correct that azithromycin can cause QT prolongation and heart problems.

the dose of azithromycin will be highest right after you take it and continue to decline as time goes on. no one knows exactly when it will be 100% safe for your heart from the azithromycin, but if you haven't had heart QT prolongation in the first day or two after taking, most likely you wont have any heart problems from teh azithromycin since the dose will only get smaller and smaller.
Customer: replied 1 year ago.
I just took the pills this morning. My cardiologist seems to think there is absolutely no worry but I am worried. I don't know what QT prolongation is but I do have PVC's non medicated and I am scared. I have been on z packs many times before finding out about this happening today and would have never taken it if I knew. How many hours after taking this medication are or will a person specifically be in a safe zone? Is there need to worry? My heart is structurally fine it's just the PVC's
Expert:  Dr. David replied 1 year ago.
no, there is no need to worry. worrying does not help your situation. worrying makes your anxiety level go up and this can cause more heart arrythmia problems.

again, there is no 100% safe zone after taking azithromycin.

the fact that you have taken azithromycin before and have not had heart beating problems is a good sign. and you took the whole course before. this time you only took one days worth. each day the amount of azithromycin in your body will be less and less and your chances of having heart problems will be less and less.

try not to stress. stressing only puts more strain on your heart.

Let me know if you have other questions.

If done for now, please click accept and leave positive feedback.

You can always reach me with "a question for Dr. David"

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Dr. David, Board Certified Physician
Category: Medical
Satisfied Customers: 29208
Experience: Experienced Physician trained in New York City. I'm ready to help.
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