- analgesic-induced nephropathy
Analgesic nephropathy refers to kidney damage caused by regular, long-term use of
pain medicines. Short-term, occasional use of these medicines does not seem to cause kidney damage.
What is going on in the body?
These medicines cause kidney damage in two different ways. The first way is called
chronic interstitial nephritis. In this disorder, inflammatory cells cause scarring and result in damaged, shrunken kidneys.
The second way is called papillary necrosis. In this case, the inner kidney dies and sloughs off, leaving a damaged kidney.
The damage due to these
pain medicines occurs slowly, over many years. It is usually not diagnosed until severe damage has occurred.
What are the causes and risks of the disease?
Analgesic nephropathy is caused by long-term, regular use of pain medicines. These medicines include acetaminophen (i.e., Tylenol), aspirin, and nonsteroidal anti-inflammatory drugs, or NSAIDs. Ibuprofen (i.e., Advil, Motrin) and naproxen (i.e., Aleve, Anaprox, Naprosyn) are examples of NSAIDs.
chronic pain are more likely to use these medicines in a way that causes kidney damage. Medicines that combine two or more analgesics together with caffeine or codeine are most likely to cause damage. These medicines are often sold as powders containing acetaminophen and aspirin with caffeine.
What can be done to prevent the disease?
Analgesic nephropathy can be prevented by limiting the use of
How is the disease diagnosed?
Diagnosis of analgesic nephropathy begins with a history and physical exam.
Kidney function tests will be ordered.
A test of blood electrolytes can help diagnose kidney damage or failure. A urinalysis can also help detect problems with kidney function.
Imaging tests, such as an ultrasound, CT scan, or a special kidney x-ray called an IVP may be ordered. These tests check the size of the kidneys and detect some problems.
biopsy of the kidney may be done as well. This involves inserting a special needle through a person's back and into the kidney. A small piece of the kidney is removed with the needle. This sample is sent to the lab for examination and testing.
Long Term Effects
What are the long-term effects of the disease?
Kidney function may improve if this condition is caught early and the person stops taking the pain medicines. However, kidney failure is often present by the time the diagnosis is made. This type of kidney damage is not usually reversible.
What are the risks to others?
Analgesic nephropathy is not contagious and poses no risks to others.
What are the treatments for the disease?
A person with analgesic nephropathy is advised to stop using
pain medicines. If the condition is caught early, this may be the only treatment that is needed. If kidney failure is present, the person will need either dialysis or a kidney transplant.
Dialysis is a procedure requires that the patient be connected to a machine that functions like an artificial kidney and "filters" the blood. This treatment is continued for life or until a kidney transplant.
The person may also need treatment for
high blood pressure.
What are the side effects of the treatments?
kidney transplant, a person must take powerful medicines to prevent the body from rejecting the new kidney. These medicines increase the person's risk of infections. They may damage the new kidney and cause other side effects. Blood pressure medicines may cause fatigue, lightheadedness, and erectile dysfunction.
What happens after treatment for the disease?
Those with only mild kidney damage who stop using
pain medicines may be able to lead a normal life. Those with kidney failure usually need treatment for the rest of their lives.
How is the disease monitored?
Kidney function is usually monitored with regular blood and urine tests. Any new or worsening symptoms should be reported to the healthcare professional.
Harrison's Principles of Internal Medicine, 1998, Fauci et al.