Allergy & Asthma Disease Management Center: Ask the Expert: Pruritis

- Pruritis -

12/5/05 re: Cause and treatment of generalized itching

I am an RN. My husband has had chronic severe itching for 2 years. It is worse at night. There is no initial rash, but he gets hives from scratching. I can scratch his arm without causing any marks, but when he scratches welts appear immediately. He is a behaviorist and cannot find any antecedents. We have changed detergent, bedding, etc. It doesn't matter if we are at home or not. He gets limited relief from loratidine, and will occasionally use atarax, but hates how it makes him feel. It is almost a daily problem. Any suggestions would be appreciated.

Generalized pruritis (itching) without any rash is often a very difficult diagnostic and therapeutic problem. I have enclosed below a portion of my response to another Ask the Expert question dealing with generalized itching with out a rash. I also suggest that you read the review of such itching written by Prof Malcolm Greaves. I have also enclosed at the bottom below my review of Greaves' article. From your description, it sounds as if your husband may have a neurogenic type of itch with secondary dermographism leading to the welts when he scratches his skin. I doubt that the itch is caused by a contact allergy (detergent, sheets, etc) since such cases almost always present with a rash as well as itching. You did not mention whether any lab studies were done in your husband's case. I think that some studies looking for a systemic condition that might be causing the itching would be worthwhile. There would include:

1) CBC with diff looking for leukocyte alterations, including eosinophilia
2) Liver function test profile- looking for evidence of biliary obstruction
3) BUN, creatinine. Fasting blood glucose (sometimes renal insufficiency and/or diabetes may be the cause)
4) serum IgE level-very high levels raise possibility of certain parasitic infections
5) generalized itching can sometimes occur with certain lymphomas.

However, the absence of other manifestations while itch has been present for two years is against the presence of lymphomas.

With regard to therapy, I would suggest a trial of cetirizine 10 mg (Zyrtec) daily. Cetirizine is a derivative of Atarax but with a lower incidence of cognitive adverse effects. A trial of doxepin at bedtime is also worth considering. Doxepin is a very potent antihistamine and also has other actions that may help control itching. However, it can be quite sedating. A dose of 50 mg (going to 100 mg if needed) at bedtime may control itch well during sleep. Other agents such as naltrexone can be considered if the above treatment is not successful.

Previous response:

In my experience, the clinical picture you describe, generalized pruritis (itching) without obvious skin lesions, is both puzzling and distressing to both patient and those trying to successfully treat the problem. I have enclosed below my review for the Current Literature section of this AADMC website of a recent review article about pruritis by Prof Malcolm Greaves, one of the leading investigative dermatologists in the world. I suggest that you read the whole article which may considerably enhance your understanding of the problem. You should be able to obtain the article through the medical library of your local hospital.

From the comments discussed in the review below, I suspect that your itching may be of the neurogenic type. Therefore, it is not surprising that the itching was not reduced significantly by treatment with the usual anti-histamines. You did not mention the dose of doxepin tried by you. In my experience, one has to build up the doxepin dose to 50-100 mg to obtain the suppressive effects on itching mentioned by Dr. Greaves. However, such doxepin doses frequently sedate. Therefore, I would try them first at bedtime where they may allow you better sleep. You may also want to try agents such as naltrexone, mentioned below

Itch and its treatment

Summary
Background - Chronic itch is a common and sometimes quite distressing symptoms that may impact significantly on the quality of life. There has been recent increasing investigation of the pathophysiology of itching and approaches to control it.

Findings - The subject of itch and its management was reviewed by Greaves and Khalife of the St. Thomas Hospital in London, UK. They stressed that itch is a complex manifestation which can be of several types: 1) Pruritogenic - itch stimulus in inflammatory skin lesions; 2) Neuropathic - due to certain diseases of neural pathways (e.g., some neuropathies); 3) Neurogenic - on a central basis due to altered balance of activation/inhibitory pathways or release of pruritogenic chemicals (e.g., opioid peptides in cholestasis); 4) Psychogenic. In some conditions (e.g., atopic dermatitis) more than one type of itching mechanism may be present.

The efficacy of treatment of itch depends on the cause of the itch.

1) In urticaria, H1 antihistamines are often effective since histamine is the major pruritogenic factor; 2) in atopic dermatitis topical corticosteroid therapy often suppresses that itch; 3) in neurogenic or neuropathic itch, H1 antihistamines and topical steroids are generally not effective. One can try broad-based ultraviolet B treatment. If this is not sufficient, try doxepin, a tricyclic compound with potent antihistamine, anti depressant actions. Doxepin appear to suppress itch by non-specific suppression of itch perception. It is best used h.s. in doses of 10-50 mg starting at the low dose and increasing as needed and tolerated. Sedation, dry mouth, and p450 enzyme pathway drug interactions must be watched for. Withdrawal of doxepin should be gradual.

Opioid mu receptor antagonists such as naltrexone (25-50 mg once daily in adults) often suppress the itch of cholestasis conditions and chronic renal insufficiency. They should not be used in patients requiring opioid treatment and/or have chronic liver disease. Nalbuphine (a combination K-receptor agonist and mu receptor antagonist) may be more effective than naltrexone alone.

Paroxetine, a selective serotonin uptake inhibitor, can be effective in suppressing itch associated with malignancies. If nausea occurs use with cisapride.

Reference
Internat Archives Allergy & Immunol 2004;135:166-72

Editor's Comments
Over the years, I have found chronic itch a frequently difficult management problem. In a few individuals, the itch was so severe and poorly controlled that it almost drove individuals to thoughts of suicide.

These thoughtful comments by leading investigators of pruritic skin diseases are well worth consideration as a basis for more effective treatment of itching. Remember, not all itching is helped by antihistamine therapy

3/14/05 re: Pruritis during hemodialysis

Any advice regarding severe pruritis in a hemodyalasis patient. I think that in this patient it is to the dialyzer membrane or the solution, because when the patient was recently admitted to the hospital for an unrelated pneumonia and she received her dialysis at the hospital she did not have the pruritis, but upon return to her ususal outpatient dialysis center the pruritis returnes.

Please pardon the delay in responding to your question. I have tried to obtain input from two experts in the adverse reactions to hemodialysis. However, I have not received a response from either individual, despite two attempts, - an unusual situation in my experience. Therefore, I will give you my thoughts as a non-expert in this field.

Pruritis is a common and often challenging adverse effect of hemodialysis, often occurring in patients who already have uremia-associated pruritis to be begin with. Opinions vary as to the mechanisms involved in hemodialysis-associate pruritis (HAP), with some, but not other, studies, finding increased plasma levels of histamine and/or serotonin. However, antihistamine are only sometimes helpful in reducing the itching. Some, but not other, studies have found that pre-treatment with antagonists of the 5-HT3 (serotonin) receptor such as tropisetron or ondansetron may significantly reduce HAP. A more encouraging report described significant reduction of HAP by topical application of 0.025% capsaicin cream to the affected skin areas 4 times daily (Nephron 1996;72:617-22). The patient should be warned that there may be some stinging at application sites during initial application of the capsaicin cream.

Your description suggests that there may be a hemodialysis-associated extrinsic factor involved in the pruritis. It is possible that no pruritis was felt during the in- patient hemodialysis because: 1) a different type of dialyzing membrane was used in the hospital or 2) some medication or other pneumonia-related factor blunted the itching sensation during that hospitalization. Therefore, I suggest that it be arranged for the patient to have another dialysis performed in the hospital in-patient unit at a time when the patient is otherwise stable. If no itching occurs again, then inquiries should be made about the types of dialysis membranes used in the two different facilities. If there is a difference, perhaps some arrangements can be made for all the dialyses to be done in the in-patient facility.

3/6/05 re: Treatment of idiopathic pruritis (itching)

I am a pharmacist, 50 & female & have had an itch of unknown etiology for two years. The itching is mostly on arms/legs with no rash. Contact with water (post bathing) really exacerbates the condition, changing my clothes brings on the itch & also I am unable to lay flat at night in a bed, having instead to lay on a Lazy Boy chair so that I am slightly elevated. Antihistamines do not work, lorazepam & alprazolam being the only meds that provide some relief. I have had 2 bone marrow biopsies in the past 4 years-the most recent this past fall-the result neutropenia, thrombocytopenia & no iron stores but the bone marrow itself is producing fine-the conclusion that something peripherally is affecting the cell counts (which they say are low-normal). I have been tested for thyroid, diabetes, liver function etc & all normal.

The itch is not temperature sensitive. I was sent to an allergist-his conclusion was that the itch is caused by stress which I don't agree with-it may be exacerbated by stress, but I don't believe it is the cause.

I have tried hormone replacement therapy (Premarin), citalopram, doxepin, prednisone (which makes the itch worsen), clonidine & dapsone all to no avail.

Do you have any suggestions for me? I am at my wit's end with this condition which is worsening every day.

In my experience, the clinical picture you describe, generalized pruritis (itching) without obvious skin lesions, is both puzzling and distressing to both patient and those trying to successfully treat the problem. I have enclosed below my review for the Current Literature section of this AADMC website of a recent review article about pruritis by Prof Malcolm Greaves, one of the leading investigative dermatologists in the world. I suggest that you read the whole article which may considerably enhance your understanding of the problem. You should be able to obtain the article through the medical library of your local hospital.

From the comments discussed in the review below, I suspect that your itching may be of the neurogenic type. Therefore, it is not surprising that the itching was not reduced significantly by treatment with the usual anti-histamines. You did not mention the dose of doxepin tried by you. In my experience, one has to build up the doxepin dose to 50-100 mg to obtain the suppressive effects on itching mentioned by Dr. Greaves. However, such doxepin doses frequently sedate. Therefore, I would try them first at bedtime where they may allow you better sleep. You may also want to try agents such as naltrexone, mentioned below.

Your limited description of the hematologic findings does not permit me to speculate about any possible relation of these to your itching. As you may have been told, certain lymphomatous malignancies can have pronounced itching, sometimes early in the course. If indicated, CT or other imaging studies may detect evidence of lymph node enlargement suggesting a lymphoma. Absence of iron stores in the bone marrow is unusual if the diet is adequate, raising the possibility of iron depletion secondary to slow, steady blood loss. A check of serum iron/ferritin levels would help explore this further. I assume that a complete blood chemistry profile was obtained in your case with normal results. Of particular interest would be tests for evidence of biliary obstruction and renal insufficiency, both of which can lead to prominent itching.

I wish you success in controlling this distressing problem.

Itch and its treatment

Summary
Background � Chronic itch is a common and sometimes quite distressing symptoms that may impact significantly on the quality of life. There has been recent increasing investigation of the pathophysiology of itching and approaches to control it.

Findings � The subject of itch and its management was reviewed by Greaves and Khalife of the St. Thomas Hospital in London, UK. They stressed that itch is a complex manifestation which can be of several types: 1) Pruritogenic � itch stimulus in inflammatory skin lesions; 2) Neuropathic � due to certain diseases of neural pathways (e.g., some neuropathies); 3) Neurogenic � on a central basis due to altered balance of activation/inhibitory pathways or release of pruritogenic chemicals (e.g., opioid peptides in cholestasis); 4) Psychogenic. In some conditions (e.g., atopic dermatitis) more than one type of itching mechanism may be present.

The efficacy of treatment of itch depends on the cause of the itch. 1) In urticaria, H1 antihistamines are often effective since histamine is the major pruritogenic factor; 2) in atopic dermatitis topical corticosteroid therapy often suppresses that itch; 3) in neurogenic or neuropathic itch, H1 antihistamines and topical steroids are generally not effective. One can try broad-based ultraviolet B treatment. If this is not sufficient, try doxepin, a tricyclic compound with potent antihistamine, anti depressant actions. Doxepin appear to suppress itch by non-specific suppression of itch perception. It is best used h.s. in doses of 10-50 mg starting at the low dose and increasing as needed and tolerated. Sedation, dry mouth, and p450 enzyme pathway drug interactions must be watched for. Withdrawal of doxepin should be gradual.

Opioid mu receptor antagonists such as naltrexone (25-50 mg once daily in adults) often suppress the itch of cholestasis conditions and chronic renal insufficiency. They should not be used in patients requiring opioid treatment and/or have chronic liver disease. Nalbuphine (a combination K-receptor agonist and mu receptor antagonist) may be more effective than naltrexone alone.

Paroxetine, a selective serotonin uptake inhibitor, can be effective in suppressing itch associated with malignancies. If nausea occurs use with cisapride.

Reference
Internat Archives Allergy & Immunol 2004;135:166-72

Editor's Comments
Over the years, I have found chronic itch a frequently difficult management problem. In a few individuals, the itch was so severe and poorly controlled that it almost drove individuals to thoughts of suicide.

These thoughtful comments by leading investigators of pruritic skin diseases are well worth consideration as a basis for more effective treatment of itching. Remember, not all itching is helped by antihistamine therapy!

9/20/04 re: Pruritis during bathing

My sister (37) has a pruritis exacerbated w after bathing since she was a teenager. There is no rash, and the pruritis is limited only to the legs and arms (especially extensor areas). The condition was not present for the last 5 years-since she had her first child. Now she is pregnant again and experiencing pruritis after each bath. Our mother had the same complaint during her younger years; she says it stopped after she had delivered her first child. Avoiding use of very hot water in bath and the use of moisturizers before and after bath seems to work a little but not always. Antihistamines (she was using them before her first pregnancy) did not work. She has no known allergies, and the blood tests are normal. Is there a disease to fulfill these criteria?

Your message did not make it clear whether the patient had pruritis all the time, aggravated w after the bath or only at times right after the bath. I am assuming that there has been no evidence that bath oils or other agents used in or after the bath is suspect in causing the pruritis. There is a condition called cholinergic pruritis by some clinicians that is triggered by hot water and other stimuli for over heating the body (e.g.-exercise). This appears analogous to cholinergic urticaria except that no wheals occur. A methacholine skin test may elicit a positive response in such cases. I cannot explain why the condition abated during the first, but not the current, pregnancy. I assume that there has been no difference in the medications used in the two pregnancies.

6/7/04 re: Cause of pruritis without rash

My brother in law is experiencing nonstop pruritis without a rash which is non-responsive to antihistamine rx. This initially occurred several weeks after epidural lumbar steroid infusion for chronic pain related to a knee injury and surgery. Pain management doctor does not believe it is related to steroid rx. He has had a bx ( x2) which showed mast cells. He has been off his pain medications (oral and a duragesic patch) for 5 weeks with no relief in itching. Itching exacerbated by sun and water but constant. Claratin and Benedryl are of no help. No rash present. No malignancy on CT scan, lab work within normal range. Etiology?

Chronic generalized pruritis without a rash is often a puzzling, frustrating situation for both patient and treating physician. I have listed below some of the conditions I have looked for in such cases. Some may have already been ruled out by studies you mentioned. I suppose that it is conceivable that the patient may be exhibiting a neurogenic based pruritis in response to some stimulatory event in the spinal cord/nerve roots following the epidural injection. However, I have not seen or heard of such an event. The presence of mast cells in the skin could be a normal finding. In systemic mastocytosis (SM) one finds: 1) clusters of mast cells in affected areas, 2) urticarial reaction when the itchy areas are rubbed (Darier's sign); 3) Increased serum tryptase levels (over 20 in 80% of SM cases); 4) increased mast cells in a bone marrow biopsy, generally in clumps.

Thoughts about idiopathic pruritis without a primary rash:

Is this a systemic condition manifest as pruritis with secondary skin manifestations? It is not unusual for the scratching of the skin in someone with prominent chronic pruritis to lead to secondary occurrence of skin lesions, including papules and scaling. Some of the systemic conditions to be considered are:

Diabetes - although fasting blood sugars may be normal, obtain 2 hour post-prandial blood sugar.

Thyroid disease - obtain Thyroxin, TSH levels

Biliary obstruction - (e.g.- idiopathic biliary cirrhosis)- obtain liver function tests, particularly directed to obstructive diseases. If abnormal, obtain anti-mitochondrial antibody tests, ultrasound studies for extrahepatic obstruction.

Chronic renal insufficiency - Should have other manifestations as well. However, check serum creatinine.

Systemic dyshidrosis - This can be checked by the response to an injection pf pilocarpine to see if normal sweat gland response. Also check whether excess dryness in the oral cavity, eyes. If these mucosal surfaces also very dry, suggests an anti-cholinergic effect, drug-induced or otherwise.

Paraneoplastic manifestation - with certain endocrine tumors (see enclosed abstract), lymphoma

HIV infection - see enclosed abstract

With regard to therapeutic trials for the pruritis, one can try topical doxepin cream (Zonalon) on affected areas. If this is not helpful, consider use of a moisturizing cream containing a local anesthetic such as lidocaine for skin areas of severe pruritis (Neutrogena makes such an over the counter product in their 'Norwegian. Formula' group, called Anti-itch Moisturizer. Make sure that the product chosen contains lidocaine since there are other products in the 'Norwegian. Formula' group.) The patient should be told that occasionally individuals develop contact sensitivity to the lidocaine with prolonged use. Systemic therapy - Doxepin is frequently more helpful for itch than standard antihistamines. Start with lower dose (25 mg) in AM, 100 mg hs if trouble sleeping. Consider adding Periactin 4 mg which sometimes helps

If all else fails, consider hypnosis therapy (see enclosed abstract)

Scand J Gastroenterol. 2003 Jun;38(6):678-80. Related Articles, Links
Intractable pruritus associated with insulinoma in the absence of multiple endocrine neoplasia: a novel paraneoplastic phenomenon.
King NK, Siriwardana HP, Coyne JD, Siriwardena AK.
Dept. of Histopathology, University Hospital of South Manchester, Withington, Manchester, UK.

Insulinoma is a rare tumor, the main symptoms of which are related to hypoglycaemia. Generalized pruritus has been described in association with the multiple endocrine neoplasia syndrome (MEN II or Sipple's syndrome) as a paraneoplastic phenomenon. Further, pruritus is known to be part of the paraneoplastic syndrome in other solid tumors. This case describes a patient presenting with symptoms of Whipple's triad (hypoglycaemic symptoms during fasting, low fasting blood sugar levels and symptoms relieved by intravenous dextrose). Magnetic resonance scanning and selective mesenteric angiography demonstrated a probable pancreatic neuroendocrine tumor. Pituitary fossa imaging and endocrine profile excluded the MEN I syndrome. Symptoms resolved after surgical removal of the tumor. Histology confirmed a pancreatic neuroendocrine tumor. The association between pruritus and insulinoma appears to be a novel paraneoplastic phenomenon.

Int J Clin Exp Hypn. 2002 Apr;50(2):149-69. Related Articles, Links
The efficacy of hypnosis in the treatment of pruritus in people with HIV/AIDS: a time-series analysis.
Rucklidge JJ, Saunders D. The Toronto Hospital, Canada.

Pruritus, or generalized itch, is a source of serious discomfort and distress in a significant minority of people living with AIDS. Anecdotal reports suggest hypnosis might be a useful treatment, leading to reductions in distress and improvements in the condition. But empirical examination of the question is notably lacking. This time-series study reports results of a 6-session self-hypnosis treatment (relaxation, deepening, imagery, and home practice) for 3 HIV-positive men suffering from pruritus, related to disease progression and/or HIV medications. Post treatment, all 3 patients reported significant reductions in daily itch severity and extent of sleep disturbance due to itch. One patient also evidenced significantly less itch distress. Another also experienced significantly less time bothered by itch. For the 2 patients on which 4-month follow-up data were available, treatment benefit across variables was stable or further improved.

2/23/04 re: Cause of pruritis with exercise

I have a 33 y/o WF patient that c/o severe pruritis and erythema (from toes to waist) that occurs when she walks over a mile or runs more than 100 yards and is greatly worsened if doing these activities in cold temperatures. Is this a type of allergic reaction or a vascular insufficiency of some sort?

I assume from your lack of mentioning it that your patient has not had the symptoms of pruritis and/or erythema at rest in or not in cold environments. If that is the case, the picture you describe sounds to me most like a relatively mild expression of exercise-induced anaphylaxis (EIA). This disorder is characterized by generalized pruritis, sometimes urticaria and (in severe cases) anaphylactic shock. Of interest, asthmatic symptoms are unusual in EIA. Thus, EIA has to be contrasted with another exercise-triggered disorder exercise-induced bronchoconstriction, in which asthmatic symptoms occur during exercise without the symptoms commonly seen in EIA.

When EIA is present, symptoms occur at the end of vigorous exercise, generally involving walking/running activities, or shortly thereafter. Although a major theory of the cause of EIA involves overheating of the involved person, there have been occasional cases in which EIA occurs particularly in cold environments. This could explain why your patient may have more symptoms when exercising in cold environments.

Some investigators feel that the diagnosis of EIA can be confirmed by obtaining serum tryptase levels before exercise and during EIA. The serum specimens obtained at those times should be frozen immediately and sent frozen to a lab that carries out tryptase levels reliably. I prefer the lab associated with Dr. Lawrence Schwartz of the Medical College of Virginia in Richmond, because they assay for both total and beta-type tryptase (most commercial labs test for only total tryptase levels). Dr. Schwartz and his colleagues have shown convincingly that it is predominantly the beta-tryptase sub-type of total tryptase that is released into the blood during anaphylactic reactions.

One puzzling aspect you described is the limitation of symptoms to areas below the waist. From what I know of EIA, this would be an unusual finding. It does not sound as if the cause is a primary vascular problem Prominent pruritis is not seen in usual vascular insufficiency disorders such as Raynaud�s Syndrome. There is an unusual vascular disorder called erythromelalgia in which regional skin redness and swelling occur in response to cold temperature exposures. Mild itching may occur, but a burning sensation is more common. This disorder is not usually related to exercise.

2/12/04 re: Chronic itching

I am a pharmacist. My brother has been having severe itching now for 7 years now he is an African from Nigeria. He always experiences deep itching all day long. Please what is the possible cause and treatment to this ailment? We have used histamines that subsides it only for it to start all over again.

Chronic itching is frequently a difficult diagnostic problem. I have enclosed below my response to a recent Ask the Expert question about itching that was similar to yours except that there is an intermittent rash. Your brother's physician may find my suggestions helpful.

Since your brother lives in Nigeria, perhaps special attention should be made to rule out a non-obvious parasitic infection. I would have blood specimens assessed for eosinophilia at least twice. If this is present, the serum IgE levels should be determined and appropriate testing for parasitic infections carried out.
_______________________________

My previous response:

When I have seen prominent itching in an adult, I have approached the diagnostic possibilities divided into two categories:

1. Is this a primary skin problem with secondary itching?

One condition which must be considered is mycosis fungoides, a type of skin lymphoma. This can present at times with an eczematous rash, often quite pruritic. A biopsy of a skin lesion, processed and examined by an experienced dermatopathologist is essential to consider this diagnosis.

The prominence of itching and rash in the folds, public area and hands raises the possibility of a parasitic infestation, particularly scabies or pediculosis pubis. Such parasitic infestations are not always limited to those in the lower socio-economic strata.Appropriate scraping/biopsy studies will explore this possibility. Also, I assume from your comments that a differential leukocyte count was done and was normal. If not done (and maybe repeat even if done) looking for peripheral blood eosinophila (elevated levels suggest m. fungoides or parasitic infestation). Candida infection is less likely, in my opinion, but can be investigated by special stains of a skin biopsy.

2. Is this a systemic condition manifest as pruritis with secondary skin manifestations?

It is not unusual for the scratching of the skin in someone with prominent chronic pruritis ti lead to secondary occurrence of skin lesions, including papules and scaling. Some of the systemic conditions to be considered are:

Diabetes- although fasting blood sugars may be normal, obtain 2 hour post-prandial blood sugar.

Biliary obstruction - (e.g.- idiopathic biliary cirrhosis)- obtain liver function tests, particularly directed to obstructive diseases. If abnormal, obtain anti-mitochondrial antibody tests, ultrasound studies for extrahepatic obstruction.

Chronic renal insufficiency - Should have other manifestations as well. However, check serum creatinine.

Systemic dyshidrosis - This can be checked by the response to an injection pf pilocarpine to see if normal sweat gland response. Also check whether excess dryness in the oral cavity, eyes. If these mucosal surfaces also very dry, suggests an anti-cholinergic effect, drug-induced or otherwise.

I am not aware of evidence that prominent pruritis is a common manifestation of idiopathic or (postulated) EBV- related chronic fatigue syndromes (CFS). As you likely know, some groups have reported an autonomic nervous system abnormality in some individuals meeting the CDC diagnostic criteria for CFS. It is conceivable that a result of such an abnormality could be excessive skin dryness.

With regard to therapeutic trials for the pruritis, one can try topical doxepin cream (Zonalon) on affected areas. If this is not helpful, consider use of a moisturizing cream containing a local anesthetic such as lidocaine for skin areas of severe pruritis (Neutrogena makes such an over the counter product in their 'Norwegian. Formula' group, called Anti-itch Moisturizer. Make sure that the product chosen contains lidocaine since there are other products in the 'Norwegian. Formula' group.) The patient should be told that occasionally individuals develop contact sensitivity to the lidocaine with prolonged use.

7/6/01 re: Pruritis in a young child

I am licensed pharmacist. My 3 year old daughter developed generalized pruritis a month and a half ago. She experiences severe itchiness at ~ 2-3 am every night, she itches less during the day. She does not have any rash. She has a history of eczema as a baby and she also has mild asthma. Allergy tests show that she's allergic to grass and tree pollens, molds, dust, dust mites, egg and peanuts. Antihistamines (Atarax 2 tsp. at night) do not relieve her itchiness. What is your recommendation for her treatment?

I have not been involved in the care of very young children for a number of years. Therefore, I referred your question to Dr. Susan Schuval, a highly experienced Pediatric Allergist and a member of the Medical Advisory Committee for this AADMC program. Her response is enclosed below.

Nocturnal pruritus is a common symptom of atopic dermatitis. Usually, itching results in the typical eczematous lesions primarily involving the flexural surfaces of the upper and lower extremities in a school-aged child. Treatment is directed at relieving pruritus (topical corticosteroids, the new tacrolimus ointment, antihistamines), reducing exposure to skin irritants (mild soaps, tepid water for bathing, light cotton clothing) and moisturizing the skin (frequent use of topical emollients).

You didn't mention whether she is avoiding eggs and peanut in her diet but this is probably advisable at the present time. In addition, she may benefit from dust mite avoidance measures (encasing the mattress and pillows in impermeable vinyl covers, washing the bedding in hot water weekly, getting rid of the stuffed animals, etc).

It sounds as though your daughter would benefit from a visit with a pediatric allergist in view of her asthma, eczema, food and environmental allergies. Over time, the eczema will most likely improve even without treatment.

6/1/00 re: Pruritis evaluation and treatment

What do you consider to be a reasonable work-up for generalized pruritis of unknown etiology in a 35-40 y.o. black man (who I believe was born in Africa). No rash or other symptoms. Pruritis seems to respond well to antihistamines but recurs when off them.
Kindly advise me of your thoughts on differential diagnosis, and work-up to rule-out or rule-in each diagnosis.

Pruritus is frequently a difficult problem both in establishing a cause and treating effectively. However, several characteristics you describe narrow down the etiologic possibilities somewhat:

The absence of rash generally rules out a primary skin problem, although occasionally itching precedes certain rashes by weeks to months. For example, T cell lymphomas of skin may not be apparent on gross examination for awhile but are detected by biopsies.

The good response to antihistamines rules against a primary "central" neurologic problem causing the itch.

Other historical factors are helpful - itching that lasts more than several weeks and is extensive (on many regions of the body) is more suggestive of a systemic process causing the itch than a localized itch. Once systemic conditions are considered, they can be divided into these categories with diagnostic approaches:

Chronic renal failure - check BUN, creatinine

Hepatic cholestasis, check bilirubin, LFT

Hemopoietic disorders - P. vera, paraproteinemia - Check CBC, SPEP

Endocrine disorders, hyperthyroid, diabetes mellitus, carcinoid - Check TSH, T3, T4, glucose, 5HIAA

Drug reaction - check history carefully. There is not always a rash. For example, some drug reactions cause cholestasis

Systemic parasitosis-particularly important in this case of a man originally from Africa.Possibilitity increases if there is blood eosinophilia.Most likely possibilities in severe itch- ascaris scabies, trichinella, onchocerciasis, Check stools, look for burrows under skin, particularly on hands

Certain malignancies - lymphoma, myeloma, M. fungoidies more than typical epidermoid tumors

Psychogenic - neurotic excoriations, delusions of parasitosis

Miscellaneous - mastocytosis, hemochromatosis, AIDS

REFERENCES
1) Seminars in Dermatol 1995;14:290-7
2) Intl J Dermatol 996;35:162-66

2/21/00 re: Treatment for chronic pruritis

I would like to know which is the most effective therapy for a patient who has a chronic pruritis. He was treated with corticosteroideal creams and IM, antihistaminics, (sedative and non sedatives); with non good results. He began with his disease three years ago. He has topics manifestations, eczema, all over his body, specially in his legs, inguinal and abdominal zone (intertrigus). He is 35 years old, he works outdoor building houses and anything else. The lab results are quietly normal and the level of Ig E is also normal. Would you mind if you could send me any suggestions about that?

Before considering therapy of chronic pruritis it is important to determine whether this is secondary to a systemic disease (cholestasis, uremia, particularly in dialysis, certain parasite infestations, and certain malignancies) since the most appropriate treatment will vary with each
condition (see enclosed abstract about opiate antagonists). Therefore, a thoroughly systemic evaluation should be carried out first.
The presence of eczematous rash in you patient suggests a primary skin problem but may also be secondary to excessive scratching/rubbing of pruritic areas (itch/scratch cycle) in what used to be called �neurodermatitis.� Therefore, a biopsy of a recent involved area may be very helpful in distinguishing atopic dermatitis (lymphocytes, eosinophil proteins though not always intact eosinophils), from irritative/neurodermatitis (variety of inflammatory cells including PMN) and mycosis fungoides (abnormal lymphocytes).

If the condition is a primary skin disorder, not responding to usual antihistamines, I suggest trials of:

Higher dose of the antihistamine, fexofenadine (120 mg q12h) recently shown to be more effective for urticaria. If not effective

Doxipen - start with 50 mg hs, increasing gradually to 150 mg hs as tolerated (can be sedative). Also, consider propofol (see enclosed abstract)

If not effective and pathology suggests atopic dermatitis, consider

Topical tracrolimus (see enclosed abstract).

Ann Pharmacother 1998 Nov;32(11):1228-30
Opioid antagonists in the treatment of pruritus from cholestatic liver disease.
Terra SG, Tsunoda SM
Duke University Medical Center, Durham, NC, USA.
The theory that pruritis from cholestasis is due to increased opiate tone appears to have merit, based on the results of the clinical trials presented above. However, although opioid antagonists relieve itching to a large extent, the itching usually is not abolished completely. Several factors may explain this lack of complete relief. The doses used in the clinical trials may have been insufficient, or duration of therapy may have been short. It is also possible that nonopioid mechanisms contribute to pruritis from cholestasis. Although effective, naloxone therapy has several limitations for long-term use, including a short half-life and large first-pass metabolism, which necessitates parenteral administration. Intravenous administration is clearly not practical for a chronic disease. Nalmefene treatment has several advantages over naloxone, with both prolonged duration of action and increased potency at the opioid receptor level. However, nalmefene is available only as a parenteral product in the US. The nalmefene studies are limited by their small sample size and short follow-up periods. Additionally, two of the studies are available in abstract form only. Based on two clinical studies, naltrexone therapy appears promising. Gradual dose titration from 25 mg/d up to a maximum of 50 mg/d may minimize withdrawal reactions. Further long-term clinical trials using objective measures that compare opioid antagonists with other therapies are needed to clearly establish the role of these agents. Potential tachyphylaxis from long-term use of opioid antagonists requires further investigation. Combination therapy may also be required, since monotherapy with either opioid antagonists or other therapies have failed to completely relieve the pruritus caused by cholestasis. Given the potential for severe withdrawal reactions, opioid antagonists should be reserved for patients refractory to other treatments.

Pruritus -- itching for a cause and relief?
Kam PC, Tan KH
Department of Anaesthesia, Royal Prince Alfred Hospital, Camperdown, N.S.W., Australia.
The mechanisms of pruritus, an unpleasant irritation on the skin that provokes an urge to scratch, are reviewed. Whilst symptomatic treatment is only partially effective, antihistamines remain the first choice of treatment. However, recent novel treatment using opiate antagonists, propofol (subhypnotic doses) and serotonin antagonists offer attractive alternatives.

J Allergy Clin Immunol 1999 Sep;104(3 Pt 2):S126-30
Treatment of atopic dermatitis: role of tacrolimus ointment as a topical noncorticosteroidal therapy.
Fleischer AB Jr Department of Dermatology, Wake Forest University School of Medicine,
Winston-Salem, NC 27157-1071, USA.
afleisch@wfubmc.edu
Atopic dermatitis is a chronic, relapsing form of eczema characterized by scaling, itchy, inflamed skin that can be triggered by an interplay of genetic, immunologic, and environmental factors. Immune dysregulation appears to play an important role in the cause of atopic dermatitis. Topical corticosteroid agents have been the mainstay of therapy for atopic dermatitis because of their broad immunomodulatory effects. However, topical corticosteroid agents are not ideal agents because when used over the long term, they may cause cutaneous atrophy and immunosuppression. Systemic corticosteroidal agents, certain antihistiminic agents, systemic cyclosporin, and phototherapy have proven value in treating patients with atopic dermatitis. In the search for a noncorticosteroidal topical agent, tacrolimus stands out as being uniquely suited for this condition. Tacrolimus affects a broad spectrum of inflammatory mediators and processes known to be relevant to atopic dermatitis pathogenesis. Tacrolimus demonstrates good percutaneous penetration and appears to have no potential to cause cutaneous atrophy. There are multiple double-blind, controlled studies demonstrating the safety and efficacy of this agent in treating atopic dermatitis. The agent may be of particular benefit in children, among whom an alternative to the chronic use of corticosteroid agents, either topically or systemically, is highly desirable.

3/10/98 re: corticosteroids and non-typical allergies

I have a patient with non typical allergies that started 1 year ago when she took a trip to Mexico (Puerto Vallarta). Since then, about every two months she presents skin reaction with rash, erythema and pruritus. It is not a typical allergic reaction and it is worsening with corticosteroids. Do you have and idea whas happening?

It is very difficult to propose possible causes of the clinical picture on the basis of the brief information you provided. Based upon the travels to Mexico and the symptoms mentioned, I wonder whether the patient may be exhibiting an immune reaction to either parasitic infestations or previous/persistent insect bites. I suggest these approaches:

Blood studies - (a) total and differential wbc (looking for eosinophils); (b) sed rate and (c) serum IgE level.

Skin biopsy of fresh rash lesion - look for eosinophils, insect parts.

Stool for ova and parasites.

Therapies you may consider:

Day time - doxipen cream applied to affected areas, non-sedating antihistamines (e.g. - Allegra).

Bedtime (if nocturnal itching is a problem) - doxipen 50-100 mg hs as tolerated by the patient (may sedate with early morning residual grogginess).

Please tell us what you think of this site.

© Copyright 1997-2009 American Academy of Allergy, Asthma & Immunology
All rights reserved