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Dr. Andrew Rynne

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Exp 50 years

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At what minimum interval can Keflex be taken for chest infection?

Answered by
Dr. T Chandrakant

General Surgeon

Practicing since :1984

Answered : 16504 Questions

Posted on Mon, 25 Aug 2014 in Infections
Question: I am takingKeflex 500 mg every 6 hours for 7 days for a chest infection.
I woke up late today and took it two hours later than I was supposed to (instead of 10am took at noon)
Do I go back to the original schedule I was on which would have meant I would take 6 hours from 10am which would be 4pm, even though I took at 12pm so would only be 4 hours since my last dose, or do i wait 6 hours from last time I took it now which would be 6pm (6 hours from 12pm)?
Answered by Dr. T Chandrakant 39 minutes later
Brief Answer:
4 PM

Detailed Answer:
Very good question.
You are taking Cefalexin 500 mg every 6 hours. This is a typical drug with a less half life so is the need to take this 6 hourly interval particularly in adults.

You are taking this medicine for the last 7 days for a chest infection- this means that the efficacy is almost completed and missing a single dose will not have any adverse effect as well as taking the next dose at 4 pm or 6 pm.

As I explained , the half life is short so you can very well take the dose at 4 pm and continue the rests at the pre-determined time.
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