NOTE: I edited the title of this post on March 29, 2020 to reflect the increasing evidence that HCQ is not useful in the prevention or treatment of COVID19. I also removed a few paragraphs from the Wall Street Journal reporting on a French  study, since the body of research since then runs contrary to its hopeful findings. As this post states, the rheumatologist I asked about this was not stating an opinion about whether HCQ works against COVID19, and is worried that the supply needed by their patients and by people with lupus might be diminished by a pointless run on the market. The information in this post about HCQ as a commonly used drug remains.

A highly reputable rheumatologist responded to my request for comment about a column by  Jeff Colyer and Daniel Hinthorn in the WSJ that holds out hope for using hydroxychloroquine to fight the Coronavirus.

The rheumatologist, who is highly respected, asked me not to use their name because they don’t want to be perceived as giving out medical advice — which this is not — and doesn’t have the time to go through their email message carefully enough to present it as a polished response. But they gave me permission to run it anonymously with those caveats. Here it is:

I give hydroxychloroquine to almost everybody who has rheumatoid arthritis and some of my patients have been on it for 20 years or more.  Of course, if patients have side effects from it I stop it and if they have improved to the point of appearing to be in full remission, I taper it down and may stop it.  There are people for whom it is not helpful by itself and is often used by me and others in conjunction with our other medicines for rheumatoid arthritis.  It is used similarly in psoriatic arthritis. I have a number of patients who have no swelling and no symptoms after treatment with hydroxychloroquine as the only “disease modifying drug.”

It is recommended to be given to virtually every patient with systemic lupus erythematosus as it is been found to improve their course, even when other medications are needed to get better control.  We also use it in other rheumatic diseases, sometimes with less evidence than for RA and SLE.

I have not used chloroquine, which is a closely related compound but one with somewhat more side effects and it is more powerful.

The side effects of hydroxychloroquine in the short term, which is what would be contemplated in treating COVID-19, are minimal to nonexistent, other than nausea and related problems, which I have almost never had patients report.  Ulcers are not caused by this.  There is a fear that people who are deficient in G6PD, an enzyme, will get hemolysis from this medication shortly after starting it;   people deficient in the enzyme G6PD could have a bad reaction to chloroquine but that is not reported now with hydroxychloroquine.  Hemolysis is destruction of red blood cells in the bloodstream and organs which could be a source of illness, however rumors that hydroxychloroquine causes this appear to be unfounded.  Several (5-10 years ago) years ago, I emailed a rheumatologist who is a world’s expert on hydroxychloroquine and asked him this question and he said that he has never seen this happen; most of us do not test for the presence of this enzyme anymore before starting hydroxychloroquine, as we feel it is not an issue.  This may not be true of chloroquine, but I have a feeling it is also not a problem.  Having to test everyone before getting this drug for COVID-19 would be a logistical difficulty given the time constraints and cost of the testing.

The rare side effects of hydroxychloroquine that might occur in the short term in my experience had been so rare as to be negligible. I have had one patient that I recall in recent years who had more vivid dreams while on this and she found that disturbing.

The vision problems that people refer to occur only after long-term use and the dangerous one is exceedingly rare.  The latter is some permanent loss of visual acuity due to retinal damage.  There was a recent study by ophthalmologists that reported that the upper dose level that we used was too high and they found evidence on new and specific testing of retinal damage at doses lower than we recommended, but these only occurred in people taking it for a long period of time, not a few weeks. Most of us in the rheumatology field have never seen damage at the frequency they report and are very disturbed by those findings.  We have been forced to lower our recommended dosages which undoubtedly has worsened some people.  In my recollection, which could be very faulty, I have had two or three people in over forty years who have had permanent visual changes after many years on the medication.  My associates have had similar experiences.

There are two other ocular problems both of which are reversible and rarely occur. One is a change in the eyeglass prescription (or requiring glasses) and the other is sparkling of lights at night. I have rarely seen either one and they are theoretically reversible by stopping the medication.  They also occur only after long term use, not a few weeks.

There is the possibility of skin pigment changing with long-term use but I do not believe I have ever had this happen to a patient.

I am sure when you review the possible side effects you will find many other side effects, however these are not common and are usually typical of any medication given to anybody for any reason.

The question of whether it is useful in COVID-19 is a separate issue about which I claim little or no expertise.  The initial trial was very small in number, but encouraging.  A real trial will be helpful but by the time it is completed, analyzed and available, we may be well past the pandemic phase, but still useful for the future.

An important study that I have thought of probably will not be done for logistical reasons.  That would be to study our patients with rheumatoid arthritis and systemic lupus who are on hydroxychloroquine to see their incidence of COVID-19 compared to a similar group of patients who are not on hydroxychloroquine.  The logistics are timing, finding a large enough sample size of patients on the drug and off the drug who are comparable, being sure the doses used are appropriate and knowing the exposures of the patient populations.

There is some concern that overuse of hydroxychloroquine by people who do not need it will deplete the supply of this important drug for our patients who are already on it and depending on it.  In fact, today I had a call from a patient who has been taking it for years and could not get it as her pharmacy was out of it.

Another medicine that rheumatologists use to treat rheumatoid arthritis and other conditions has been found in a small study to be successful in treating COVID-19.  That medicine is tocilizumab with the brand name of Actemra.  It interferes with IL-6.

The study the rheumatologist is proposing sounds ultra-interesting and possibly consequential.

Categories: science dw