Background/Objectives. Chronic benzodiazepine (BDZ) use is frequently maintained beyond recommended durations due to neuroadaptation, psychological dependence, and withdrawal-related issues. Passiflora incarnata L., herba (P. incarnata) has shown anxiolytic and GABAergic activity that may mitigate withdrawal symptoms, while cognitive-behavioural therapy (CBT) targets maladaptive beliefs and behaviours sustaining BDZ misuse. This study investigates the independent and interactive effects of P. incarnata and CBT on BDZ dose reduction during a three-month tapering program. Methods. This retrospective observational study included 186 outpatients with anxiety or depressive disorders in clinical remission undergoing BDZ tapering, of whom 93 received a dry extract of P. incarnata as adjunctive treatment and 93, matched for diagnosis, age and sex, followed a standard tapering protocol. BDZ doses were assessed at baseline and three months. CBT was recorded as a binary variable based on the information documented in the medical records. An ANCOVA was performed to assess the impact of CBT and P. incarnata on BDZ reduction (change in mg diazepam equivalents), adjusting for sex, age, education, baseline anxiety and depression scores, initial BDZ and antidepressant dosage. A subgroup analysis was conducted to investigate the role of P. incarnata dosage in BDZ reduction. Results. Both CBT and P. incarnata were associated with significantly greater reductions in BDZ dosage at three months (CBT: p = 0.005, effect size: 0.032; P. incarnata: p < 0.001, effect size: 0.128). A significant interaction between CBT and P. incarnata was also observed (p = 0.037, effect size: 0.018), indicating a synergistic effect when both interventions were combined. Baseline sociodemographic characteristics, BDZ and antidepressant dosage and symptom severity did not differ significantly between groups. Patients taking 400–600 mg of P. incarnata dry extract showed a higher BDZ reduction compared to those taking 200 mg. Conclusions. These findings suggest that P. incarnata and CBT exert independent yet complementary effects in supporting BDZ tapering. Their combination appears to enhance dose reduction beyond either intervention alone, supporting a multimodal approach that addresses both neurobiological and psychological components of BDZ addiction. Prospective controlled studies are needed to confirm these results and to clarify their impact on long-term discontinuation outcomes.
Carminati et al. (Wed,) studied this question.