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Is It Possible To Have Delayed Reaction To Bactrim?
Posted on
Sat, 14 Feb 2015
Medically reviewed by
Ask A Doctor - 24x7 Medical Review Team
Sun, 15 Feb 2015
Answered on
Tue, 3 Mar 2015
Last reviewed on
Question : hello. is it possible to have a delayed reaction to Bactrim? I have taken Bactrim for 6-7 days and broke out in hives.
Brief Answer:
Most drug allergies develop after 5 to 7
Detailed Answer:
Hello!
Welcome to Healthcare Magic.
It is very common to experience symptoms of an allergic reaction to a drug after several days of taking the drug. Most drug allergies develop after 5 to 7 days of exposure to the drug.
If a person with a drug allergy has been exposed to the drug or similar drugs earlier,then it is more likely to have an immediate allergic reaction or after some hours to days.
During the earlier exposure, the immune system start to form antibodies against the drug and the symptoms may develop several days after taking the drug.
In the second exposure ,the reaction will be quick and the rash may start quickly, within the first day or two after taking the drug.
Since you have been taking Bactrim for 7 days and then broke out in hives, most likely it is an allergic reaction to Bactrim.An allergic reaction can be delayed and not occur until 8 to 10 days after starting the drug if you haven't been exposed before to this drug.
Hope it helps.
Let me know if you have any other question or doubts to clarify.I will be happy to help you.
Kind regards,
Dr.Rovena Murati
Most drug allergies develop after 5 to 7
Detailed Answer:
Hello!
Welcome to Healthcare Magic.
It is very common to experience symptoms of an allergic reaction to a drug after several days of taking the drug. Most drug allergies develop after 5 to 7 days of exposure to the drug.
If a person with a drug allergy has been exposed to the drug or similar drugs earlier,then it is more likely to have an immediate allergic reaction or after some hours to days.
During the earlier exposure, the immune system start to form antibodies against the drug and the symptoms may develop several days after taking the drug.
In the second exposure ,the reaction will be quick and the rash may start quickly, within the first day or two after taking the drug.
Since you have been taking Bactrim for 7 days and then broke out in hives, most likely it is an allergic reaction to Bactrim.An allergic reaction can be delayed and not occur until 8 to 10 days after starting the drug if you haven't been exposed before to this drug.
Hope it helps.
Let me know if you have any other question or doubts to clarify.I will be happy to help you.
Kind regards,
Dr.Rovena Murati
Above answer was peer-reviewed by :
Dr. Chakravarthy Mazumdar
Answered by
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