Healthpoint advice re treating uraemic pruritus Diagnosis: Treatment:

Healthpoint advice re treating uraemic pruritus
Diagnosis:
•
•
•
Occurs in stage 5 chronic kidney disease (eGFR <15 or on dialysis) or late stage 4
chronic kidney disease.
Is not associated with a rash per se but there may be significant secondary
manifestations from excoriation.
Always consider the differential diagnoses of allergic reaction, scabies and other
pruritic skin conditions.
Treatment:
No one treatment works for all sufferers of uraemic pruritus. From the available evidence
the below treatments are most likely to be helpful:
1. "Lifestyle" advice - itch is worse when the sufferer is hot so wearing loose cool
clothing and taking tepid showers and baths to avoid overheating may be helpful.
Keeping fingernails short will help reduce skin trauma from scratching. I
2. Dry skin may cause and contribute to itch so if the skin is dry prescribe liberal use
of emollients, avoiding any perfumes or other potential irritants (including sodium
lauryl sulfate which is often found in aqueous cream). I 2 Suitable emollients
.include Health E fatty cream, cetamacrogol cream (also known as non-ionic
cream) and 10% glycerine in the cetamacrogol cream. Other over the counter
products which may have additional benefits in terms of restoring the skin's
barrier function include Cetaphil Restoraderm, A veeno and Dermosoft.
3. Uraemic pruritus is not histamine mediated so oral anti-histamines are only useful
for their sedating properties to aid sleep at night. I
4. Gabapentin is the treatment with the most evidence of benefit (three randomized
controlled trials) in uraemic pruritus.' 4 5 It probably interrupts glutamate
mediated transmission of pruritus in the dorsal horn of the spinal cord." 7
Gabapentin is entirely renally cleared so dose adjustment is mandatory for
uraemic pruritus. Starting dose for haemodialysis patients is 100mg three times
per week post dialysis but this can be increased as tolerated to around 400mg post
dialysis. I Peritoneal dialysis patients and those not receiving dialysis with eGFR
<15 should start with 1OOmg on alternate days and the dose can be titrated uf as
tolerated.f 9 When eGFR is > 15 a starting dose of 100mg nocte can be used. See
below for additional guidance on using gabapentin.
5. For those who are unable to tolerate gabapentin there is also evidence that
Evening Primrose oil, which contains gamma-linolenic acid (GLA), may be
helpful. Blackrnores Evening Primrose Oil contains 1OOmg GLA per capsule and
1 capsule twice to three times daily delivers the dose of GLA used in the
randomized controlled trial that demonstrated efficacy in uraemic pruritus. 10
Blackrnores Evening Primose oil is available over the counter from pharmacies
and supermarkets for around $40 for 190 capsules.
6. Broadband UV therapy has been found to be effective. I I 12 This can be accessed
by referral to a dermatologist.
Further information on gabapentin prescribing
Gabapentin prescribing is limited under special authority criteria in New Zealand.
The pathogenesis of uraemic pruritus is poorly understood but it intimately involves
c-fibre nerve endings in the skin and has similarities with neuropathic pain including
peripheral and central sensitization phenomena. I Special authority criteria for
gabapentin in New Zealand require the patient to have had a trial of a tricyclic
antidepressant prior to gabapentin for the treatment of neuropathic pain. There is no
evidence that tricyclic anti-depressants are effective for uraemic pruritus. 13 Tricyclic
anti-depressants may be contraindicated in some patients with chronic kidney disease.
Tricyclic anti-depressants are not recommended in individuals with cardiovascular
disease which is highly prevalent in those with renal failure. 14 Dry mouth, an anticholinergic side effect oftricyclic antidepressants, may make it difficult for
individuals on a fluid restriction (all dialysis patients) to adhere to this. When using
gabapentin, side effects to watch for include somnolence, dizziness, fatigue, ataxia
and nausea and vomiting. Hypersensitivity reactions can occur. Patients should be
advised to avoid driving if they feel sleepy on gabapentin and they should not drive
during dose titration. Gabapentin is also reported to increase the incidence of
depression and suicidal ideation. IS This needs to be weighed against the evidence that
uraemic pruritus is not only distressing and adversely effects quality of life but it has
been associated with increased mortality in dialysis patients. 16 It is possible to
administer dose increments ofless than lOOmg, which is the smallest capsule size, but
this should be discussed with a pharmacist to determine if it is feasible for the
individual patient. In those not having dialysis with deteriorating renal function it is
necessary to watch for side effects and consider dose reduction as renal function
declines.
References
I Murtagh F, Weisbord SD. Symptoms in renal disease; their epidemiology, assessment, and management.
In: Chambers EJ, Brown EA, Germain MJ (eds). Supportive care for the renal patient. Second edition.
Oxford: Oxford University Press, 2010; 103-38.
2 Okada K, Matsumoto K. Effect of skin care with an emollient containing a high water content on mild
uremic pruritus. Ther Apher Dial 2004; 8(5): 419-422.
3 Gunal AI, Ozalp G, Yoldas TK, et al. Gabapentin therapy for pruritus in haemodialysis patients: a
randomized, placebo-controlled, double-blind trial. Nephrol Dial Transplant 2004; 19: 3137-3139.
4 Naini AE, Harandi AA, Khanbabapour S, et al. Gabapentin: a promising drug for the treatment ofuremic
pruritus. Saudi J Kidney Dis Transplant 2007; 18(3): 378-381.
5 Razeghi E, Eskandari D, Ganji MR, et al. Gabapentin and uremic pruritus in hemodialysis patients. Renal
failure 2009; 31: 85-90.
6 Koga K, Chen T, Li X-Y, et al. Glutamate acts as a neurotransmitter for gastrin releasing peptide-sensitive
and insensitive itch-related synaptic transmission in mammalian spinal cord. Molecular pain 2007; 7:47.
7 Rose MA, Kam PCA. Gabapentin: pharmacology and its use in pain management. Anaesthesia 2002; 57:
451-462.
8 Ashley C, Currie A (eds). The renal drug handbook. Third edition. Adingdon (Oxon): Radcliffe Medical
Press, 2009.
9 Brennan F, Siva B, Crail S. Appropriate assessment of symptom burden and provision of patient
information. In: ANZSN renal supportive care guidelines. Nephrology 2013; 18: 401-454.
10 Yoshimoto-Furuie
K, Yoshimoto K, Tanaka T, et al. Effects of oral supplementation with evening
primrose oil for six weeks on plasma essential fatty acids and uremic skin symptoms in hemodialysis
patients. Nephron 1999; 81: 151-159.
11 Gilchrest BA, Rowe JW, Brown RS, et al. Ultraviolet phototherapy for uremic pruritus: long-term results
and possible mechanism of action. Annals of internal medicine 1979; 91: 17-21.
12 Gilchrest BA, Rowe JW, Brown RS, et al. Reliefofuremic
pruritus with ultraviolet phototherapy.
Engl
J Med 1977; 297: 136-138.
13 Yosipovitch G, Bernhard JD. Chronic pruritus. N Engl J Med 2013; 368: 1625-1634.
14 Medsafe Data Sheets for amitriptyline and nortriptyline (January and February 2013).
15 Medsafe Data Sheet for Neurontin February 2013.
16 Pisoni RL, Wikstrom B, Elder SJ, et al. Pruritus in haemodialysis patients: international results from the
dialysis outcomes and practice patterns study (DOPPS). Nephrol Dial Transplant 2006; 21: 3495-3505.