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Forum Name: Valvular Heart Diseases

Question: More questions about Long QT!

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 emmylala2003 - Tue Feb 08, 2005 3:12 pm

Hello and thank you for responding. I was wondering, why would you suggest that I ask my doctor to prescribe antibiotics that do not prolong the qt interval, if I have nothing to worry about?

I thought that certain medications, including some antibiotics were contraindicated ONLY in people who have a long qt interval. So, if chances are that I do not have it, would it be ok for me to take any antibiotics prescribed, including those that may cause a prolonged qt interval?

I had bronchitis about two weeks, my doctor prescribed tripack (which I beleive is erythromycin, similar to Zithromax) I was already feeling better when my doctor prescribed it, so I didnt fill the prescription because I knew that erythromicn was an antibiotic that was known to cause prolonged qt interval. Now, I'm beginning to feel sick again, a little cough, slight nasal congestion, sneezing and sore throat. So rather than seeing my doctor again, I wanted to fill my tripack prescription and take that. Is this ok, or should I see my doctor again, just in case its not bronchitis again but something else?

One last question, which types of antibiotics do not prolong the qt interval? are cephalosporins a good alternative? I'd like to know, so that I might educate my doctor, since I'm not sure she knows.
 Dr. Yasser Mokhtar - Thu Feb 10, 2005 4:37 pm

User avatar Dear Emmy,

You don't have to worry because like in erythromycin it is quite rare to see qt prolongation but it happens sometimes, but, it you are still so worried about it to the extent that you are not willing to take antibiotics, then at this point ask your doctor to prescribe antibiotics that do not prolong the qt interval (even if this was a rare side effect of the dryg).

Yes, you can take any antibiotic putting in mind that may be this antibiotic has a rare side effect such as prolongation of the qt interval.

i think you should call your doctor to tell him about this set back in your condition before you refill your erythromycin because she might want to to give another antibiotic.

The antibiotics that can cause long qt interval are macrolide group, erythromycin and zithromax and the like. Some antibiotics belonging to a group called fluroquinolones. But once more it is rare to have this side effect. Penicillins and cephalosporins don't have this side effect.

hank you very much for using our website and i hope that this information helped.

Yasser Mokhtar, M.D.

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