Intensity of Withdrawal Symptoms During Opioid Taper in Patients with Chronic Pain-Individualized or Fixed Starting Dosage?

Objective. Controlled opioid withdrawal is recommended for patients with chronic noncancer pain (CNCP) with insufficient pain reduction or intolerable side effects while on opioid treatment. Few studies have investigated the management of opioid withdrawal (OW). Most common are protocols with an individualized starting dosage (ISD), calculated from the last opioid intake. After two cases of overdose, we introduced a novel withdrawal protocol using a low fixed starting dosage (FSD) for safety reasons. The present study compares the intensity of withdrawal symptoms using the Subjective Opioid Withdrawal Scale (SOWS) and incidences of serious adverse events (SAE) and dropouts in each taper schedule in 195 CNCP patients with OW in an inpatient facility. Methods. Two protocols were compared: FSD (2014-2016): N = 68, starting dose: 90mg morphine/d; and ISD (2010-2014): N = 127, starting dose: 70% of the patient's daily morphine equivalent dose (MED). Outcome criteria: primary: mean daily SOWS score during the first 10 days (16 questions, daily score 0-64); secondary: change in pain intensity on a numeric rating scale (0-10), rate of dropouts and SAEs. Statistics: Student test, Mann-Whitney U test, chi-square test, analysis of variance, P<0.05. Results. The mean daily SOWS score was lower in the FSD group (14.969.4 vs 16.1610, P<0.05) due to a lower rate of high-intensity withdrawal symptoms (12.4% vs 17.6%, P<0.01), particularly in patients on >180 mg MED (9.7% vs 18.4%, P<0.01). Pain intensity decreased after withdrawal, and the incidence of SAEs and dropouts was low in both groups. Conclusions. The FSD protocol provides a lesser burden of withdrawal symptoms and equal patient safety. It can be recommended for OW in CNCP patients.