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Alcoholism
Having a Reaction to Reactions
When is a reaction not really a reaction?
Posted June 5, 2016
Sometimes patients say they had “a reaction” to a treatment, but they don’t always mean what doctors have in mind when they use the word, “reaction.”
Doctors divide reactions into two kinds: 1) Allergy: the body mounts an immune response to something taken by mouth or applied to the skin; and 2) Intolerance: a medicine produces discomfort not related to immunity.
An example of the first is penicillin allergy. Even a tiny amount in an allergic individual can produce hives, or an itchy rash all over the body.
An example of the second, intolerance, is severe heartburn when a patient takes the antibiotic doxycycline. This is caused by irritation of the esophagus during swallowing. The same patient can tolerate doxycycline, even in full dose, if the drug is taken with food, or if a different form of doxycycline that is kinder to the GI tract. That wouldn’t be true if she were actually allergic.
When our patients say they are “having a reaction,” however, it’s often hard for us to tell what they mean, since what they describe doesn’t fit either what we mean by “allergy” or “intolerance.” At times it’s hard for us to tell what our patients actually do mean.
For instance, there’s an acne medicine that comes in the form of a moisture lotion. Steven calls to say he can’t use it because “it dries me out completely.” How does a moisture lotion dry somebody out?
Other acne medicines have alcohol in them and can be drying. But how to make sense of Emily, who says that when she put it on her cheeks, “it dried me out all over,” even where she didn’t apply it.
Another acne drug, minocycline, is deposited in developing bones. We can’t prescribe it to patients under the age of 8, since doing that would discolor visible teeth. (After that age, any discoloration only affects back teeth that no one but the dentist ever sees.)
But the other day Bettina—who is 58--told me, “I can’t take minocycline because it changes the color of my teeth.”
If we look skeptical at reports like these, patients often respond by saying, “My body is prone to strange reactions that no one else gets.”
Maybe so, but that makes it hard for doctors to know what to do with people who don’t react the way other people do.
When a customer in a cosmetic store or pharmacy who returns a skincare cream because it gave her “a reaction,” the store takes it back, no questions asked. This is not just good business practice; in that context both the customer and the salesperson use the word “reaction” the way laymen do, not the way doctors do.
When patients tell me about reactions I am pretty sure are not really allergic, I sometimes suggest they wait a few days for the skin to calm down, then try the cream that bothered them again, but just on one spot in front of the right ear, just to see if whatever happened happens again. A lot of time, nothing happens, he goes on to use the cream, and we never do figure out what happened the first time.
If patients are afraid to try the same medicine again, though, I suggest they us something else—if I have something else to suggest.
But sometimes there is no other useful treatment to try, or else I run out of options. This doesn’t happen very often, but it may. For instance, last month Susan told me that she had to stop taking the antibiotic cefadroxil after two days, because it made her “tired.” We tried minocycline, but that made her “irritable.” (I have prescribed each of these antibiotics a couple of dozen times a week for decades, and can’t recall a single person stopping either drug for those reasons.) “My body is prone to strange reactions that no one else gets,” Susan explained. Then she asked for a third option.
“I honestly don’t know what to suggest,” I apologized. “Since your body reacts in ways that other peoples’ bodies don’t, I just can’t predict what some other treatment will do to you, even if it hasn’t done it to anyone else.”
I teach my students to listen to reports of reactions with patience and respect. First of all, strange reactions do happen. Second, patients who are afraid of taking or using something are hard to convince otherwise, even if we’re sure the “reaction” was not what they thought it was.
Sometimes, I have to confess, my patience wears thin. Just last week Brian, a young man for whom I had prescribed an antibiotic gel for acne, told me he was only using it on his right cheek. “That’s where I still have pimples,” he said. “My left cheek is clear. I can’t use the gel on that side, because it makes pimples come out.”
I tried wrapping my brain around that: Brian was convinced that the same cream that was clearing up acne on one side of his face was making acne come out on the other side.
Thankfully, no harm will come to Brian for putting an acne gel on just one cheek, but not every medical situation allows us such flexibility. At those times, doctors have to insist that not every “reaction” is actually a reaction, and do our best to convince our patients not to be afraid to try what we think will help.
