In this study, researchers from Argentina assessed the efficacy and safety of naltrexone for the short- and long-term treatment of pruritus of cholestasis.
The research team studied 20 patients with pruritus and cholestasis.
The team obtained a baseline pruritus score over a 1 week period.
They then randomized patients to receive 50 mg per day of naltrexone, or placebo, for 2 weeks.
After a 1-week washout period, patients were crossed-over to the other therapy for a further 2 weeks.
The team assessed pruritus daily using a visual analogue scale (VAS).
|In 45% of the patients receiving naltrexone, pruritus decreased by more than 50%, compared to basal value.|
|Journal of Hepatology|
Any patients whose pruritus decreased more than 50% of basal following naltrexone treatment, received a further 50 mg per day for 2 months.
The research team found the mean basal VAS to be similar in both groups.
However, the VAS showed greater and more significant changes with naltrexone treatment, than with placebo (p<0.0003).
They found that in 45% of the patients receiving naltrexone, pruritus decreased by more than 50%, compared to basal value.
In 5 patients pruritus disappeared completely.
They team observed no significant changes in serum biochemistry.
The majority of adverse events due to treatment occurred during the first 48 hours of naltrexone therapy. These were consistent with opioid withdrawal-like phenomena; they spontaneously disappeared 2 days after starting treatment.
Dr Rubén Terg's team concluded, "Naltrexone can be considered as an alternative option to treat pruritus of cholestasis".
"In the current study, side effects were transient and did not require specific medication."
In a related editorial in the same publication Dr Anthony Jones from the Academic Medical Center, Amsterdam, The Netherlands, also discusses the use of opiate antagonists for pruritus of cholestasis.
He concludes, "The observation that the oral administration of an opiate antagonist to cholestatic patients (who had not received an opiate) often precipitates a transient opioid withdrawal-like reactions".
Furthermore, "Supports the hypothesis that opioidergic tone in the central nervous system is increased in cholestasis, and strengthens the rationale for treating the pruritus of cholestasis with an opiate antagonist".