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Q: antibiotics and lactose intolerance ( Answered 5 out of 5 stars,   0 Comments )
Subject: antibiotics and lactose intolerance
Category: Health > Conditions and Diseases
Asked by: jadbal-ga
List Price: $30.00
Posted: 19 Apr 2005 10:54 PDT
Expires: 19 May 2005 10:54 PDT
Question ID: 511406
I was prescribed a 5 dose Zithromax Z-pack (a powerful anti-biotic)
more than two months ago for bronchitis.  Ever since that time, I have
lactose intolerant.  I diagnosed this condition myself by noticing a
correlation between dairy and acidic diarrhea.  I am wondering if this
sounds like a proper diagnosis, if this is a common side effect of
Zithromax, how long it might last, and if there is medication to
remedy the problem.  I would ask a doctor but it is cheaper to ask
here first.  I have never been lactose intolerant before.  I am a 20
year old and otherwise healthy male.
Subject: Re: antibiotics and lactose intolerance
Answered By: journalist-ga on 19 Apr 2005 12:12 PDT
Rated:5 out of 5 stars
Greetings Jadbal,

Following is varied information dealing with your query, and diarrhea
appears to sometimes occur when antibiotics are ingested.

"ANTIBIOTICS: Antibiotics kill the good bacteria in your bowel along
with the bad bacteria for which you're taking the antibiotic. Eating
yogurt with live cultures or taking acidophilus tablets during the
course of the medication will help. If diarrhea connected with
antibiotics becomes troublesome, you should consult your doctor."

"Certain antibiotics can trigger temporary lactose intolerance by
interfering with the intestine's ability to produce the lactase

"One of the most common is antibiotic-associated diarrhea (AAD) ? a
potentially serious condition that affects up to 20 percent of people
receiving antibiotic therapy.  AAD occurs when antibiotics disturb the
natural balance of "good" and "bad" bacteria in your intestinal tract,
causing harmful bacteria to proliferate far beyond their normal

"Many antiviral drugs, such as nelfinavir and ddI, list diarrhea as a
common side effect. A number of antibiotics like clarithromycin,
azithromycin, and ciprofloxacin can also cause diarrhea."


"What should I watch for while taking azithromycin? Tell your
prescriber or health care professional if your symptoms do not
improve. Contact your prescriber or health care professional as soon
as you can if you get an allergic reaction to azithromycin, such as
rash, itching, difficulty swallowing, or swelling of the face, lips or
tongue. If you get severe or watery diarrhea, do not treat yourself.
Call your prescriber or health care professional for advice. Antacids
can stop azithromycin from working. Do not take an antacid at the same
time as azithromycin."
"Description: Azithromycin is a semisynthetic antibiotic belonging to
the macrolide subgroup of azalides and is similar in structure to
erythromycin. Although azithromycin is significantly more expensive,
it can be dosed once daily and produces less GI intolerance than does
"What side effects may I notice from taking azithromycin? Side effects
that you should report to your prescriber or health care professional
as soon as possible: Rare or uncommon: -dark yellow or brown urine
-difficulty breathing -severe or watery diarrhea -skin rash, itching
-irregular heartbeat, palpitations, or chest pain -vomiting -yellowing
of the eyes or skin Side effects that usually do not require medical
attention (report to your prescriber or health care professional if
they continue or are bothersome): -diarrhea -dizziness, drowsiness
-hearing loss -headache -increased sensitivity to the sun -nausea
-stomach pain or cramps -tiredness -vaginal irritation, itching or
From drug reference azithromycin at

So azithromycin produces "less" GI intolerance yet doesn't appear to
bypass diarrheal problems.  I recommend you phone and/or visit your
physician concerning this problem, and he/she may inform you that you
are not permanently lactose intolerant but that the milk products you
now ingest are simply not reacting well with you system due to reduced
lactase enzyme.

Until you can get an appointment with or phone your doctor regarding
this, you may consider adding some yogurt to your diet.  It may take a
few days or weeks for your system to rebalance.

I am not a physician and this answer is not meant to reflect diagnosis
or dietary advice.  I suggest you consult a physician for the best
advice on this topic.  However, Internet references are abundant for
this topic.

Should any links not work correctly, please request a clarification
before rating my answer as I am happy to respond further.

Best regards,


antibiotics cause lactose intolerance
antibiotics cause diarrhea
Zithromax side effects lactose intolerance
Zithromax side effects diarrhea
antibiotics acidic diarrhea
azithromycin side effects lactose intolerance [NOTE: Zithromax is a
brand name for azithromycin]
azithromycin lactase enzyme
jadbal-ga rated this answer:5 out of 5 stars

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