Comparison of Gabapentin With Doxepin in the Management of Uremic Pruritus

Comparison of Gabapentin With Doxepin in the Management of Uremic Pruritus: Pilot Study

This is a single blind randomized trial to compare efficacy and side effects of Gabapentin with Doxepin. Hemodialysis patients with uremic pruritus at one dialysis center of Saint George Hospital University Medical Centre were included in this study. Patients were divided into 2 groups to receive either 10 mg Doxepin daily or Gabapentin at a dose of 100mg after each hemodialysis session (increased as tolerated) for 4 weeks, after which patients were treated reversley. Pruritus severity and its effect on quality of life will be assessed by using visual analog scale (VAS), 5-D pruritus scale and dermatology life quality index (DLQI). Include patients will have to fill these forms at baseline and at end of week1, week2 and week4

Pruritus is one of the frustrating skin manifestations of advanced renal failure. Many options have been used for the management of uremic pruritus (UP) such as Pregabalin, Gabapentin, Doxepine and Desloratidine. Gabapentin, a GABAergic drug, has been found to be effective in the treatment of uremic pruritus. Doxepin, a potent antihistamine drug, is used orally or topically in many pruritic conditions such as UP, idiopathic pruritus, atopic dermatitis, neurogenic, or psychogenic pruritus and, in the management of the UP in hemodialysis patients.

No comparative head to head study between Gabapentin and Doxepine has been conducted to date. The aim of this study was to compare Gabapentin and Doxepin in treatment of uremic pruritus in hemodialysis patients.

Inclusion Criteria:

• prevalent patients undergoing HD with UP for at least three months
• any medications with antipruritic effects to be discontinued one week before the study
• Hemodialysis performed for 3-4 h thrice weekly via a low flux polysulphonedialyser [1.3-1.6 m2 surface areas] using bicarbonate and/or acetate dialysis fluid
• well controlled Calcium, Phosphorus and iPTH levels

Exclusion Criteria:

• patients labeled high risk of fall (Having a score more than 16/20 using part 1 from Falls Risk Assessment Tool (FRAT)
• patients taking drugs that interact with doxepin or gabapentin
• patients with hepatic failure
• patients with hyperthyroidism
• patients with narrow angle glaucoma
• patients with heart block or decompensated heart failure or hypotension (defined as systolic blood pressure less than 90 mmHg) or myocardial infarction in the past three months
• history of allergy to gabapentin or doxepin
• uncontrolled psychiatric diseases
• pregnant patients
• patients with psoriasis, atopic dermatitis or any other condition that can justify the pruritus