Question 1

is it possible for you to take cephalexin if you r allergic to penicillins?

Accepted Answer

Yes: Cross reactivity between the two classes are low so Cephalexin is not contraindicated in penicillin allergy patients. You should have your prescribing physician to follow you for any signs of reactions and get proper treatment.

Question 2

can i take cephalexin if i am highly allergic to penicillin? i have not taken penicillin since i was very young.  reaction of hives convulsions

Accepted Answer

Penicillin allergy: You have what is known as an immediate hypersensitivity reaction to penicillin derivatives and should never be given one, since this is life-threatening. There is said to be cross-hypersensitivity reactions to cephalosporins in 5% of pen allergic persons, and 0.1% of these have a severe reaction. My advice would be not to take a cephalosporin antibiotic unless there was no alternative.

Question 3

i am allergic to penicillin is it safe to take cephalexin for infection in the urine.

Accepted Answer

Probably should not: Cephalexin is related to penicillin and there is a chance of an allergic reaction.  Many people who are allergic to penicillin can take Cephalexin safely, but i would not suggest it.

Question 4

i'm allergic to penicillin, can i take keflex?

Accepted Answer

Maybe: Penicillins (like amoxil) & cephalosporins (like keflex) are both beta-lactam antibiotics named because of their ringed chemical structure. Allergy to penicillins is sometimes directed against this ring, and an allergic reaction may also occur if a similar antibiotic is taken. It is estimated that about 10% of penicillin-allergic patients are also allergic to cephalosporins like keflex.

Question 5

if i'm allergic to penicillin is it safe to take keflex pulvales?

Accepted Answer

No: If you are truly allergic to penicillin, you should avoid all penicillin derivatives and the first generation cephalosporins.  Keflex is a first gen. Cephalosporin and may cross react with penicillin.  See a board certified allergist to help you determine if penicillin is a true allergy for you.

Question 6

is it a bad idea for someone allergic to penicillin safely take keflex, a cephalosporin?

Accepted Answer

Yes: Cephalexin (keflex) is a first generation cephalosporin and a very close cousin to penicillin.  Though it is not 100% true that all penicillin allergic individuals are also allergic to cephalexin, there is a high likelihood of that happening.

Question 7

i took keflex and had hives all over my body, was told not to use penicillin or sporin dugs. hives again from  neosporin, can i take the shingles shot?

Accepted Answer

Shingles shot: reaction to antibiotics should not affect you getting the shingles vaccine.  They are unrelated.  However yes you could be allergic to the shingles vaccine but there is no way to know until you get it.  The good news it is only a one time shot so you won't need boosters.

Question 8

i got allergy from penicillin  45 yrs ago when i was 8 yrs, since then i have not used it. now due to uti i am given keflex. shd i take it. advice plz?

Accepted Answer

Complex question: it depends on the type of reaction when you were exposed to penicillin, what's comforting though is that it took place 45 yrs ago, and possibility of having a reaction with cephalexin is minimal, now 2 options: either ask your doctor for an alternate drug, or, take the cephalexin first dose in your doctor's office under his/her supervision, serious reactions occur within the 1st hr of the 1st dose

Question 9

i m allergic to penicillin keflex azithromiacin my daughter has scarlet fever and i m worried about what i can take if i get it ?

Accepted Answer

Don't panic: Scarlet fever is an acute febrile illness, primarily affecting children, caused by group a beta-hemolytic streptococci.  Clinical manifestations include fever, sore throat, and fine sand-paper like rash caused by a toxin produced by the strep.  Although penicillins are antibiotics of choice, there are other antibiotics that are effective.  Your doctor will know. A throat culture is helpful.

Question 10

if i got an allergic reaction from cephalexin, does that mean i am also allergic to penicillin?

Accepted Answer

No: There is indeed crossreactivity, but:
-if you are allergic to cephalosporins like cephalexin, and have had penicillin with no problem in the past, most patients can continue taking penicillin without problems. 
-if you have not had penicillin since this reaction to cephalexin, you should see a physician who could to test you to penicillin, ideally an allergist.

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Doctor answers about:

Can i take penicillin wuth cephalexin

A member asked:

Is it possible for you to take cephalexin if you r allergic to penicillins?

A member asked:

Can i take cephalexin if i am highly allergic to penicillin? i have not taken penicillin since i was very young. reaction of hives convulsions

A member asked:

I am allergic to penicillin is it safe to take cephalexin for infection in the urine.

A member asked:

I'm allergic to penicillin, can i take keflex?

A member asked:

If i'm allergic to penicillin is it safe to take keflex pulvales?

A member asked:

Is it a bad idea for someone allergic to penicillin safely take keflex, a cephalosporin?

A member asked:

I took keflex and had hives all over my body, was told not to use penicillin or sporin dugs. hives again from neosporin, can i take the shingles shot?

A member asked:

I got allergy from penicillin 45 yrs ago when i was 8 yrs, since then i have not used it. now due to uti i am given keflex. shd i take it. advice plz?

A member asked:

I m allergic to penicillin keflex azithromiacin my daughter has scarlet fever and i m worried about what i can take if i get it ?

A member asked:

If i got an allergic reaction from cephalexin, does that mean i am also allergic to penicillin?

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