Gettysburg Medical News
The Clinical View
by P.E. Hoffsten, M.D.
16 January 2002

HOW TO TAKE CARE OF ITCH

     This January there has been an epidemic of upper respiratory tract infections with sore throat and sniffles, sinus problems and a few pneumonias.  In one office, seven out of seven people working there developed severe sore throats.  It turned out that the infectious agent was an unusual form of streptococcus not sensitive to the Zithromax 3 day antibiotic often used. Several of the infected people that tried this and had not gotten well.  At that point, a throat culture returned identifying the unusual form of streptococcus that would require a different antibiotic.

       One of the individuals who was infected, started the second antibiotic called clindamycin to which this organism was sensitive.  Normally, we would have used Penicillin but she was allergic to that.  After reviewing the sensitivities of the organism and her allergy history, clindamycin seemed the best choice.

       So she starting taking clindamycin 1 pill 3 times a day for a week and the sore throat got better.  But now one of the ugly rules of life rears it’s head: “Nothing is ever easy and nothing is ever simple”.  About two days after her antibiotic was completed, she began to develop itching on her hands, on the abdomen, and on the scalp and later on the same day, she began to itch diffusely all over.  Initially, there was no rash seen but by the end of the day, there were small red spots developing on her skin.  These spots were about a quarter inch in diameter, very irregular in shape and the itching was getting much worse.  This is a classical presentation of a drug reaction.  She was having an allergic reaction to the antibiotic that had been started 10 days before.

      Several points are of interest in answering questions about this problem.  First, she said that she had taken that antibiotic many times before and had never had a problem.  She found it hard to believe that the antibiotic was the cause of the rash.  She was told that allergic reactions are not predictable.  A person may take a drug for a long time and never be allergic to it but then develop an allergy.  Sometimes, the infecting agent can be a helper in creating the allergy with the antibiotic.  Secondly, she was concerned that the rash didn’t happen while she was taking the antibiotic but didn’t occur until it was done.  This is the classical way reactions present.  An allergy takes between 7 and 15 days to develop.  If a person were to take an antibiotic for a week and then stop, the rash and allergy may not develop until 10 days after the antibiotic was started as occurred in this lady.

       Her third concern was what was she going to do now when she needed dental work, or antibiotics for other purposes now that she was allergic to three different classes of antibiotics. Fortunately, our pharmaceutical industry continues to develop new antibiotics and there are still many that will be effective of a different chemical class to which she is not allergic.

      The fourth question and one of most concern was how do we stop the itch.  This rash was intensely distracting.  She was not able to carry on normal activity.  By far the most effective and first step in treating “hives” (the allergic rash) is the antihistamine family of drugs.  There are many products on the market, Benadryl being one that is available over the counter.  While Benadryl has significant side effects of dry mouth and sleepiness, some of the prescription antihistamines were designed to avoid these side effects and still be useful in preventing the itch. The usual prescribed dose of antihistamine is often not enough to completely deal with the rash of a drug reaction.  Sometimes two and three times the normal amount of drug may have to be used to get complete relief.

       The second mainstay of treatment is the use of the cortisone family of steroid drugs.  The antihistamine will stop the itch within a half hour of the time that it started although incompletely.  The cortisone family of drugs won’t work for the first day but by the second day, will definitely tone down the intensity of the reaction and cut short the duration of the reaction. The cortisone family of drugs can be given either as a pill by mouth, or as an injection of a delayed release product.  Sometimes, a single injection of delayed release cortisone can completely arrest the allergic reaction.  The cortisone works by telling the white blood cells to quit getting so excited and leave the person’s skin alone.  The side effects from the use of cortisone on a short term basis is negligible.  There maybe a little bit of an upper effect or a little bit of an increased appetite for a few days but these side effects wear off quickly.  To the people that use these medications, very small side effects seem well worth the trade off of stopping the itch.

       Rarely, drug reactions can be very severe so that the person’s skin blisters and may slough off completely.  These are very dangerous reactions and require hospitalization. Fortunately, they are very rare.

       There are many other forms of itch besides drug reactions which cause about ¾ of all cases of hives.  A few people will get hives simply from emotional upset or from various hereditary conditions.  These are more difficult to deal with.

       There are other causes of itch besides allergic reactions.  Some that are unusual include iron deficiency.  People that have slow blood loss and become anemic can develop severe itching with no rash and no obvious reason for the itch.  Checking a blood count and iron levels can sometimes make a diagnosis.  Alternatively, individuals who have kidney failure develop various hormonal imbalances that result in severe itch.  Considerations in these situations are more complex and are best dealt with by the healthcare professionals at your local clinic.