Delayed crises following benzodiazepine withdrawal: deficient adaptive mechanisms or simple pharmacokinetics? Detoxification assisted by serum-benzodiazepine elimination tracking

OBJECTIVE: Rapid relapses after successful withdrawal occur even in apparently motivated benzodiazepine (BZD)-dependent patients. Regardless of known personality or biological (re-adaptation) issues, the aim of this open-label, single-arm, seminaturalistic study was to search for any detoxification errors contributing to failures. METHODS: The data came from 350 inpatients. Based on serum-BZD evolution criteria, the procedure was divided into four stages: substitution, accumulation, elimination and post-elimination observation. After switching the patients to a long-acting substitute (diazepam), to prevent data falsification due to unwanted overaccumulation, the doses were expeditiously reduced under laboratory feedback until accumulation stopped. With the start of effective elimination, the tapering rate slowed and was individually adjusted to the patient’s current clinical state. The tracking of both serum-BZD concentration and the corresponding intensity of withdrawal symptoms was continued throughout the entire elimination phase, also following successful drug withdrawal. Detoxification was concluded only after the patient's post-elimination stabilization. RESULTS: Regardless of various initial serum-BZD concentration levels and the customized dose-reduction rate, and despite the novel lab-driven actions preventing initial overaccumulation, elimination was systematically proven to be protracted and varied within the 2- to 95-day range after the final dose. Within this period, withdrawal syndrome culminated several times, with varying combinations of symptoms. The last crisis occurrence (typically 2–3 weeks after withdrawal) correlated with the final serum-BZD elimination. The factors that prolonged elimination and delayed the final crisis were patient age, duration of addiction, adjunct valproate medication and elimination stage start parameters growing with former overaccumulation. CONCLUSIONS: The low-concentration detoxification stage is critical for patients’ confrontations with recurring withdrawal symptoms. Underestimated elimination time following drug withdrawal and premature conclusions of detoxification expose patients to unassisted withdrawal crises. Concentration tracking defines proper limits for medical assistance, preventing early relapses. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s00228-021-03205-x.