| Drug-induced Lupus
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from the lupus foundation. For information about lupus or to locate the chapter nearest you, visit their
website at www.lupus.org or call our information
request line toll-free at 1-800-558-0121 (en Espaņol, 800-558-0231).
Drug-Induced Lupus Erythematosus
Robert L. Rubin, Ph.D.
Associate Member,
Department of Molecular & Experimental Medicine
The Scripps Research Institute
La Jolla, California
Drug-Induced Lupus Erythematosus (DILE or DIL)
Drug-induced lupus erythematosus is a side-effect of long-term use of certain medications.
Specific criteria for diagnosing drug-induced lupus have not been formally established.
However, some symptoms overlap with those of SLE. These include:
- Muscle and joint pain and swelling
- Flu-like symptoms of fatigue and fever
- Serositis (inflammation around the lungs or heart that causes pain or discomfort)
- Certain laboratory test abnormalities.
Once the suspected medication is stopped, symptoms should decline within days. Usually
symptoms disappear within one or two weeks. Drug-induced lupus can be diagnosed with
certainty only by resolution of symptoms and their failure to recur after stopping the
medication.
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What Medicines Cause Drug-Induced Lupus?
Lupus-inducing drugs are typically those used to treat chronic diseases. No obvious common
denominator links the drugs that are likely to cause lupus. The list includes medicines
used to treat:
- Heart disease
- Thyroid disease
- Hypertension
- Neuropsychiatric disorders
- Certain anti-inflammatory agents and antibiotics.
At least 38 drugs currently in use can cause DILE. However, most cases have been
associated with these three:
- procainamide (Pronestyl)
- hydralazine (Apresoline)
- quinidine (Quinaglute).
The risk for developing lupus-like disease from any of the other 35 drugs is low or
very low; with some drugs only one or two cases have been reported.
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What Is The Likelihood of Developing DILE or Drug-Induced Lupus Erythematosus
- It usually takes several months or even years of continuous therapy with the medication
before symptoms appear.
- For the high-risk drugs such as procainamide and hydralazine, only 5-20 percent of
people treated for one to two years at currently used doses will develop drug-induced
lupus.
- With most of the other drugs, the risk is less than 1 percent that those taking the
medication will develop DILE.
Who Is Most At Risk for Drug-Induced Lupus Erythematosus
- There is no evidence that people with SLE are more likely to develop drug-induced lupus.
- The use of procainamide, hydralazine, isoniazid, or various anticonvulsants has not been
associated with an increase in SLE disease activity or onset of flares.
- The major risk factor for developing drug-induced lupus is chronic, long-term use of a
drug known to cause this problem.
- Usually DILE occurs in males over 50 years old, because they have a higher chance of
developing chronic diseases that require this type of continuous medication: procainamide
or quinidine is prescribed for cardiac arrhythmias, and hydralazine is prescribed for
hypertension.
- The high female-to-male ratio associated with SLE is not a distinguishing feature of
drug-induced lupus.
- Some evidence suggests that whites are more likely than blacks to develop DILE.
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Is Heredity A Factor In DILE or Drug-Induced
Lupus Erythematosus
The only well-defined genetic risk factor in DILE is the slow drug acetylation
phenotype. Many medications change biochemically as they pass through the liver, and
people who are "fast acetylators" more efficiently metabolize procainamide and
hydralazine to a form that does not induce lupus. Therefore, people who are "slow
acetylators" are at higher risk for developing lupus-like disease from these two
drugs. This is a characteristic of approximately 50 percent of the North American white
and black populations.
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Why Does Drug-Induced Lupus Occur?
Considerable controversy and disagreement exists about the processes that lead to
drug-induced autoimmunity. Drug-induced lupus was first identified almost 50 years ago and
has been the subject of many research studies. However, the causes of this disorder are
only beginning to be understood.
- One view is that the offending drugs interfere with enzymes that would otherwise
suppress certain genes. The result is a non-specific hyperimmune condition.
- Considerable circumstantial evidence suggests that it is not the drug itself but the
metabolic change the drug undergoes in the body that makes it able to react with the
immune system.
- One possibility is that when these drug metabolites bind to certain proteins,
drug-protein complexes are produced. These then activate drug-specific lymphocytes, which
damage surrounding tissue or stimulate neighboring lymphocytes.
- In one mouse study, a drug metabolite was placed in the thymus (one of the main lymphoid
organs that forms T lymphocytes). The result was production of the type of autoantibodies
that are seen in drug-induced lupus. These findings point to the human thymus as the place
where the DILE process begins.
- It is possible that more than one process causes drug-induced lupus. Although most cases
of SLE probably arise spontaneously, the similarities in the signs and symptoms between
SLE and DILE suggest that similar immune problems are involved in both diseases.
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Symptoms Of DILE or Drug-Induced Lupus
Erythematosus
- People with drug-induced lupus most often complain of flu-like symptoms, especially
muscle and joint pain.
- Sometimes the symptoms appear gradually and worsen when the person is treated with the
implicated drug for many months.
- In other people, the onset of symptoms is rapid.
- Features of drug-induced lupus are essentially the same regardless of the implicated
medication. (However, there is some suggestion that certain symptoms are more common with
particular drugs.)
- Symptoms are mild in most people, but can become debilitating if the individual
continues to take the offending medication.
- By the time a diagnosis is made, most people will have one or more of these symptoms:
DILE Should Not Be Confused With Medication Side Effects
Drug-induced lupus should not be confused with the drug side-effects that often occur
after short-term therapy for gastrointestinal, neurologic, or allergic symptoms. These
problems usually occur within a few hours to days of taking the medication.
Drug-induced lupus typically comes after many months or years of continuous therapy
with the causative drug.
Laboratory Testing For DILE or Drug-Induced
Lupus Erythematosus
As with SLE, most people with drug-induced lupus develop antinuclear antibodies, or
ANAs, although those with a form of drug-induced lupus related to quinidine
often are ANA-negative. The ANAs in drug-induced lupus are primarily autoantibodies that
are able to react with a histone-DNA complex, which is the major component of the nucleus
of all cells.
A special laboratory test to detect certain antibodies to this histone-DNA complex is a
sensitive marker for lupus-like disease brought on by many drugs. Hydralazine
is the exception, as only about one-third of people with DILE have this type of
anti-histone antibody.
- Although the ANA or anti-histone test can help to confirm a diagnosis of DILE, it is not
useful to periodically test people who have no symptoms.
- Most medications with a tendency to induce lupus-like disease also produce (at a much
higher frequency) a mild type of anti-histone antibody not associated with symptoms.
- There is no evidence that people who develop only ANA without symptoms are at increased
risk for future development of DILE symptoms.
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The Process Of DILE or Drug-Induced Lupus
Erythematosus
In most people who develop drug-induced lupus, the symptoms and ANA appear at about the
same time. After discontinuing the offending medication, drug-induced ANA should gradually
disappear. If the ANA is truly drug-induced, its gradual decline after the medication is
discontinued can confirm that the diagnosis was correct. A return to normal can take many
months and sometimes years.
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How Is Drug-Induced Lupus Different From SLE?
- Acute onset SLE, especially in young women, is usually not confused with drug-induced
lupus, due to the general lack of skin disease, kidney disease, and the milder symptoms.
- Oral ulcers, photosensitivity, hair loss, and central nervous system disease are also
very rare in DILE.
- However, the onset of SLE in elderly people often fails to show the disease's classical
features:
- Sometimes the symptoms can be just like the symptoms of drug-induced lupus.
- However, many elderly people take several medications.
- Therefore, knowing that one of these drugs has a risk for producing lupus-like
side-effects should raise suspicion.
Laboratory tests can also be used to distinguish these two diseases. People with SLE
usually have more abnormal immunological features (although both people with SLE and
people with DILE have ANA and anti-histone-DNA antibodies).
If possible, the suspected medication should be discontinued or replaced with one that
is similar. Symptoms that go away within a week or two without additional treatment are
likely to be from drug-induced lupus, rather than due to SLE.
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Treatment Of DILE
The most important aspect of treating drug-induced lupus is to recognize the medication
that is likely to be causing the problems. Its use can then be discontinued. This step is
often sufficient to improve the symptoms within a few days, which will indicate that
symptoms were drug-induced.
Individuals will probably improve more quickly if non-steroidal anti-inflammatory drugs
(NSAIDs) are then used.
- These medications can also reduce symptoms of other rheumatic diseases and therefore may
confuse diagnosis.
Corticosteroids may be appropriate for individuals with severe symptoms of drug-induced
lupus, which would include:
- severe inflammation of several joints
- inflammation of the sac around the heart
- in rare cases, kidney disease.
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Prognosis
By definition, drug-induced lupus is "cured" merely be stopping the offending
medication. However, the complete disappearance of symptoms can sometimes take months, and
the disappearance of abnormal autoantibodies may take a few years.
After recovering from DILE, some people may develop this syndrome again if not enough
time has passed before they again begin to take the same medication. It would be best to
avoid a medicine that has previously caused drug-induced lupus.
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DILE With SLE?
There is often the desire to attribute a spontaneous disease to environmental factors.
In cases of SLE it seems especially justified to implicate drugs shown to induce
lupus-like disease. The medical literature mentions that selected cases of true SLE might
have been "triggered" by a lupus-inducing drug. It is not possible to prove or
disprove this idea.
Researchers continue to search for environmental factors that might cause and sustain
systemic lupus and other autoimmune diseases, based on the phenomenon of drug-induced
lupus. However, the vast majority of people with DIL are fully cured simply by
discontinuing use of the responsible medicine.
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Drugs Reported to Induce Lupus-Like Disease
Agent |
Risk |
|
Agent |
Risk |
Antiarrhythmics |
|
|
Antithyroidals |
|
Procainamide (Pronestyl)
|
high |
|
Propylthiouracil
(Propyl-thyracil) |
low |
Quinidine (Quinaglute) |
moderate |
|
|
|
Disopyramide (Norpace) |
very low |
|
|
|
Propafenone (Rythmol) |
very low |
|
|
|
| |
|
|
Antibiotics |
|
Antihypertensives |
|
|
Isoniazid (INH) |
low |
Hydralazine (Apresoline) |
high |
|
Nitrofurantoin (Macrodantin) |
very low |
Methyldopa (Aldomet) |
low |
|
Minocycline (Minocin) |
low |
Captopril (Capoten) |
low |
|
|
|
Acebutolol (Sectral) |
low |
|
|
|
Enalapril (Vasotec) |
very low |
|
Anti-Inflammatories |
|
Clonidine (Catapres) |
very low |
|
D-Penicillamine (Cuprimine) |
low |
Atenolol (Tenormin) |
very low |
|
Sulfasalazine (Azulfidine) |
low |
Labetalol (Normodyne, Trandate) |
very low |
|
Phenylbutazone (Butazolidin) |
very low |
Pindolol (Visken) |
very low |
|
|
|
Minoxidil (Loniten) |
very low |
|
Diuretics |
|
Prazosin (Minipress) |
very low |
|
Chlorthalidone (Hygroton) |
very low |
| |
|
|
Hydrochlorothiazide (Diuchlor h) |
very low |
Agent |
Risk |
|
Agent |
Risk |
Antipsychotics |
|
|
Miscellaneous |
|
Chlorpromazine (Thorazine) |
low |
|
Lovastatin (Mevacor) |
very low |
Perphenazine (Trilafon) |
very low |
|
Levodopa (Dopar) |
very low |
Phenelzine (Nardil) |
very low |
|
Aminoglutethimide (Cytadren) |
very low |
Chlorprothixene (Taractan) |
very low |
|
Alpha-interferon (Wellferon) |
very low |
Lithium carbonate (Eskalith) |
very low |
|
Timolol eye drops (Timoptic) |
very low |
| |
|
|
|
|
Anticonvulsants |
|
|
|
|
Phenytoin (Dilantin) |
very low |
|
|
|
Carbamazepine (Tegretol) |
low |
|
|
|
Trimethadione (Tridone) |
very low |
|
|
|
Primidone (Mysoline) |
very low |
|
|
|
Ethosuximide (Zarontin) |
very low |
|
|
|
| |
|
|
|
|
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The Lupus Foundation of America
The Lupus Foundation of America (LFA) was established in 1977 to educate and support those
affected by lupus and find the cure. The LFA supports research, education, awareness,
patient services, and advocacy. The Lupus Foundation of America is the only nationwide
organization exclusively serving individuals, families and friends affected by lupus. The
LFA has hundreds of local chapters and support groups throughout the United States, as
well as international affiliates around the world.
The LFA is a grassroots, volunteer-driven organization. Contact the LFA or the chapter that serves your area to
find out how you can become involved in our mission.
Become a Lupus E-Advocate and help pass federal legislation that will benefit people with
lupus. Send an e-mail message to advocacy@lupus.org
and enter SUBSCRIBE in the subject line. You'll receive periodic advocacy updates and
other breaking lupus news and information.
For information about lupus or to
locate the chapter nearest you,
visit our website at www.lupus.org or call our
information request line toll-free at 1-800-558-0121 (en Espaņol, 800-558-0231).
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