One very common and distressing symptom that affects individuals with chronic kidney disease is itching (pruritus). The itching can be so severe that it can lead to a poor quality of life. The exact number of patients who develop itching with chronic kidney disease is not known but the numbers are grossly underestimated, as many clinicians never ask their patients about this problem. Sadly, many kidney patients with itching have no idea that the condition can be managed effectively. Hence, it is vital that patients with kidney disease who develop itching ask their healthcare providers about potential treatments.
Why does one develop itching during kidney disease?
Although the exact pathophysiology of itching in kidney disease has not been clarified, researchers indicate that in kidney disease, the receptors or nerves that play a role in itching become hypersensitive.
Further, in patients with kidney disease the body accumulates all types of toxins that make these itching receptors extra sensitive. Also, the process of kidney failure causes profound changes in several hormonal systems that deal with the bones which alter the activation of the itching fibers.
Furthermore, kidney disease itself also causes structural changes in the skin due to dehydration and induces immune disregulation- all of which lead to the firing of the nerves associated with the sensation of itching.
Finally, it is believed that patients with kidney disease also develop changes in perception of pain and/or itching in the brain so that even minor irritation leads to an intense desire to scratch.
How common is itching in patients with kidney disease?
Itching is very common in patients with kidney disease. Itching affects people of all races and ethnicities. In about 40% of patients with kidney disease, the itching is classified as severe. As the kidney disease progresses, the intensity of itching also increases. The itching persists even in patients who are on dialysis.
However, among individual patients the intensity of itching is variable and it is difficult to predict who may develop severe itching. For unknown reasons, some patients develop continuous intense itching and others develop mild intermittent itching episodes.
Over the past 2 decades, the incidence of itching among patients undergoing dialysis has dropped, chiefly due to improvements in dialysis access and frequency.
The itching in kidney patients does vary among the different populations and geographical areas. Data indicate that kidney patients in France have a low risk of itching but those living in the UK have higher reported rates of itching. Similar variability in itching has been reported among Asian countries.
Overall, itching in kidney patients living in less developed countries is low; this could be due to the fact that either the diagnosis has not been made or the number of patients with kidney disease may be less.
There is no difference in the itching rates among patients who are on hemodialysis or those who undergo peritoneal dialysis.
How does the itching in kidney disease present?
Itching in kidney failure patients has a varied presentation. In some kidney patients, the itching may occur soon after the diagnosis and in others, it may occur much later.
The majority of patients, however, will complain of itching daily and in many cases, the itching will occur at night and ruin sleep. The itching in most cases is generalized; meaning it occurs on almost every part of the body. Overall, the intensity of itching is worse at night compared to the day time. The itching in kidney disease can also be aggravated by the following factors:
- Excess heat
- Physical activity
- Exposure to very cold weather
- Taking a warm or hot shower
- Use of certain medications like opiates and water pills
Once itching has started in patients with kidney disease, it does not stop right away. In most cases, it may persist for many months or even years.
How is the diagnosis of itching associated with kidney disease made?
Because there are many causes of itching, the diagnosis of kidney disease-related itching is not always easy to make. Many of these patients are also on medications that can cause itching.
So the first step is to ensure that the patient has evidence of kidney failure and then try to eliminate other causes like eczema, stress, fungal infections, and skin disorders like dermatitis.
In all cases, once the individual has been diagnosed with itching associated with kidney disease, the healthcare provider will classify the degree of the problem and then recommend a treatment. Today, there are itching questionnaires available that can be used to assess the response to treatment and quality of life.
How does itching affect the quality of life in patients with kidney disease?
Itching is a symptom that significantly affects the quality of life. The constant itching leads to poor sleep and marked loss of energy. The constant scratching leads to excoriation marks and sometimes skin breakdown.
In fact, the itching is also known to cause depression and anxiety in many patients with kidney disease. Patients typically feel drained from the constant scratching and this can also affect relationships.
Itching in kidney failure patients seldom occurs alone; most patients also report fatigue, lack of energy, and aversion to the cold at the same time. Finally, patients who undergo a kidney transplant tend to have very low or no episodes of itching.
What is the treatment of itching in kidney disease?
In general, most patients require some type of treatment for symptom relief otherwise the itching leads to severe disability. There are two basic treatments for itching:
1) Topical- the local application of a medication at the site of itching
2) Systemic drug that you take by mouth to relieve the itching.
The topical treatments
- All patients with itching should understand that the key to treatment is to hydrate the skin. Thus the majority of topical treatments like moisturizers, emollients, and creams are designed to replenish the water under the skin. This usually leads to quick relief of itching. The key is to apply an oil-based moisturizer as the results are sustained. Also, the oil or moisturizer has to be applied at least 2-4 times a day. Baby oil is as good a moisturizer as any product on the market.
- For those patients whose itching is moderate, then additional topical agents may include the use of capsaicin 0.03% ointment, which is available over the counter. While capsaicin may produce an initial burning sensation, it will provide good relief from itching. Another option is 1% pramoxine hydroxide lotion (requires a prescription) which can provide quick relief of itching.
- There are several systemic medications that can be used to manage itching that isn’t controlled with topical medications. These include gabapentin (need a prescription) which can be used in patients both on dialysis or without dialysis. The drug is relatively safe and quickly provides itching relief. However, the drug needs to be taken regularly or the itching will return. Pregabalin is an alternative for patients who cannot tolerate gabapentin. Other treatments include the use of the novel antidepressants (Sertraline, prozac) which lower the urge to itch and also enhance the mood.
- A third class of drugs includes the use of antihistamines. These drugs have been around for decades and while large scale studies are lacking, anecdotal reports indicate that antihistamines can provide relief from itching. However, the major downside to the use of antihistamines is that they can cause lethargy, sedation and confusion, which can be marked in patients with kidney disease. Thus, antihistamines are not the first-choice treatment for itching in kidney disease.
- Over the past few years several other medications have been used to manage itching and they include naltrexone and nalfurafine. Both these work on the opiate receptors and do work well but they are very expensive. These drugs are of last resort.
Phototherapy was once widely used to treat itching in kidney patients before the availability of the above medications. Ultraviolet light (UVB) can provide good symptom relief but is only effective for mild cases; the treatment can be done at home and is cost-effective. However, users should be aware that the long term effects of UVB remain unknown and it’s important to speak to your healthcare provider before embarking on this therapy
Changes in lifestyle
There are no universal guidelines to manage itching in patients with kidney disease but all experts agree that the patient should make changes in the lifestyle to reduce the intensity and frequency of teaching. These changes include the following:
- Avoid prolonged hot showers as they can wash the body oils and make the itching worse. Instead, use slightly warm or tepid water for a short time. You can have a bath in lukewarm water and supplement the water with oatmeal or baking soda.
- Moisturize the skin with baby oil at least 3-4 times a day. Apply the moisturizer liberally, particularly before bedtime and after a bath. Use fragrance-free products like Eucerin and Cetaphil, which are readily available over the counter
- Keep a list of triggers or situations that make your itching worse and avoid them. This may include excess heat, rough clothing, too much sun or cleaning products used in the home.
- If your skin is inflamed or red from the constant scratching, you may want to use a non-prescription drug over the counter (hydrocortisone cream). Or you can try calamine lotion, menthol or capsaicin- all of which produce a cooling effect on the skin.
- Humidity: Keep the home on the cool side and ensure that the humidifier is on. Itching usually is worse in hot and dry conditions.
- Some people may find application of plant or leaf gels soothing. There are reports indicating that use of tea tree oil, aloe vera or cooling menthol can provide fast relief from itching.
- If you are constantly scratching, this can damage your skin and even lead to infections. Hence, keep your nails trimmed and wear gloves at night.
- Reduce stress in your life as it is known to promote itching. If you are stressed seek counseling, acupuncture, behavior modification, yoga, mediation or deep breathing.
- If the itching prevents you from getting adequate sleep, try and use an antihistamine just before bedtime. Not only will it reduce the itch, the medication will promote good sleep.
- Wear appropriate clothing: To reduce itching wear light fabric garments made of cotton. Avoid nylon and polyester; cotton is known to keep the skin cool and decrease the sensation of itching
- Avoid the use of fragrances, perfumes, aftershaves, hairsprays and skincare cosmetics- all these products contain a plethora of chemicals that are known to cause dryness and itching
Natural Options To Support Healthy Skin
- Activated Charcoal: Activated charcoal binds to toxins, drugs and most importantly kidney toxins. This helps rid the body of all these substances.
- Charcoal is made from coal, wood, or other substances. It becomes “activated charcoal” when high temperatures combine with a gas or activating agent to expand its surface area.
Speak to your provider: before you decide to take a new supplement, herb or an over the counter medication, speak to your healthcare provider to ensure that there will be no interactions between these products and your prescribed medications. In most cases, the present-day treatments with changes in lifestyle can reduce itching and significantly improve the quality of life in kidney disease.