12 doctors weighed in:
I have been on antibiotic for 1 1/2 days for severe uti. How long does it take for antibiotics to work?
12 doctors weighed in

Dr. John Leander Po
Internal Medicine - Infectious Disease
4 doctors agree
In brief: Within a day
Great question. Since uti's are painful, effective therapy can alleviate this symptom within a day.
However, other symptoms, depending on the severity of infection, may take up to a week (fever, malaise) or so to abate (eg.Flank pain).If symptoms smolder, inform your prescriber immedately- antibiotics may need to be adjusted. Hopefully, a urine culture was intially done to guide antibiotic choice.

In brief: Within a day
Great question. Since uti's are painful, effective therapy can alleviate this symptom within a day.
However, other symptoms, depending on the severity of infection, may take up to a week (fever, malaise) or so to abate (eg.Flank pain).If symptoms smolder, inform your prescriber immedately- antibiotics may need to be adjusted. Hopefully, a urine culture was intially done to guide antibiotic choice.
Dr. John Leander Po
Dr. John Leander Po
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Dr. Mary Ann Block
General Practice
4 doctors agree
In brief: Depends
It is important to finish the antibiotic once it is started.

In brief: Depends
It is important to finish the antibiotic once it is started.
Dr. Mary Ann Block
Dr. Mary Ann Block
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1 comment
Dr. George Klauber
Sometimes effective within 24 hours, usually within 3 days provided the bactreium is sensitive to the medication. It is always best to a urine culture and sensitivities before before starting an antibiotic.
Dr. John Leander Po
Internal Medicine - Infectious Disease
3 doctors agree
In brief: Burning pain <1day
Since uti's are painful, effective therapy can alleviate the symptom of pain/burning on urination within a day.
However, other symptoms, depending on the severity of infection, may take up to a week (fever, malaise) or so to abate (eg.Flank pain).If symptoms are gone in a few days, it is important to complete the prescribed course! or else you risk getting a recurrence of the infection.

In brief: Burning pain <1day
Since uti's are painful, effective therapy can alleviate the symptom of pain/burning on urination within a day.
However, other symptoms, depending on the severity of infection, may take up to a week (fever, malaise) or so to abate (eg.Flank pain).If symptoms are gone in a few days, it is important to complete the prescribed course! or else you risk getting a recurrence of the infection.
Dr. John Leander Po
Dr. John Leander Po
Thank
Dr. George Klauber
Pediatrics - Urology
2 doctors agree
In brief: 1 - 3 days
Usually start to have effect by 1 1/2 days.
Did your dr. Get a urine culture which would show whether you are on correct antibiotic. Urine culture result usually available after 24 hours, but sensitivities, indicating to which antibiotics the UTI bacteria are sensitive to takes 48 hours. May need to change antibiotics if ineffective or bacteria are resistant to your antibiotic.

In brief: 1 - 3 days
Usually start to have effect by 1 1/2 days.
Did your dr. Get a urine culture which would show whether you are on correct antibiotic. Urine culture result usually available after 24 hours, but sensitivities, indicating to which antibiotics the UTI bacteria are sensitive to takes 48 hours. May need to change antibiotics if ineffective or bacteria are resistant to your antibiotic.
Dr. George Klauber
Dr. George Klauber
Thank
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