Adverse drug events associated with nortriptyline compared with paroxetine and alternative medications in an older adult population: a retrospective cohort study in Southern California.

OBJECTIVE: Investigate risk for falls, fractures and syncope in older adult patients treated with nortriptyline compared with paroxetine and alternative medications. DESIGN: Retrospective cohort study. SETTING: The electronic medical record and prescription drug database of a large integrated healthcare system in Southern California. PARTICIPANTS: Ambulatory patients, age ≥65 years diagnosed with depression, anxiety disorder or peripheral neuropathy, dispensed one or more of ten study medications between 1 January 2008 and 31 December 2018. MAIN OUTCOME MEASURES: HR for falls, fractures and syncope with exposure to study medications adjusted for patient demographic variables and comorbidities. RESULTS: Among 195 207 subjects, 19 305 falls, 15 088 fractures and 11 313 episodes of syncope were observed during the study period. Compared with the reference medication, nortriptyline, the adjusted HRs (aHRs) for falls were statistically significantly greater for: paroxetine (aHR 1.48, 95% CI 1.39 to 1.57), amitriptyline (1.20, 95% CI 1.08 to 1.33), venlafaxine (1.44, 95% CI 1.34 to 1.56), duloxetine (1.25, 95% CI 1.12 to 1.40), fluoxetine (1.51, 95% CI 1.44 to 1.59), sertraline (1.53, 95% CI 1.44 to 1.62), citalopram (1.61, 95% CI 1.52 to 1.71) and escitalopram (1.37, 95% CI 1.21 to 1.54), but not gabapentin (0.95, 95% CI 0.89 to 1.02). For fractures, compared with nortriptyline, aHRs were significantly greater for: paroxetine, venlafaxine, duloxetine, fluoxetine, sertraline, citalopram, escitalopram and gabapentin, with aHRs ranging from 1.30 for gabapentin to 1.82 for escitalopram; risk was statistically similar for amitriptyline. For syncope, the aHRs were significantly greater for: paroxetine, venlafaxine, fluoxetine, sertraline and citalopram, with aHRs ranging from 1.19 for fluoxetine and paroxetine up to 1.30 for citalopram and sertraline; risk was similar for amitriptyline, duloxetine, escitalopram and gabapentin. CONCLUSIONS: Compared with therapeutic alternatives, nortriptyline was found to represent a lower risk for falls, fractures and syncope, versus comparator medications, except for a few instances that had equivalent risk. The risk for these adverse events from paroxetine was comparable to the alternative medications.

Effects of Zuojin Pill (Rhizoma Coptidis and Fructus Evodiae preparation) on the pharmacokinetics and side effects of venlafaxine in humans.

Venlafaxine (VEN), a first-line antidepressant, and Zuojin Pill (ZJP), a common herbal medicine consisting of Rhizoma Coptidis and Fructus Evodiae, are high likely co-administered in China. ZJP could significantly inhibit VEN pharmacokinetics in vitro and in rats through suppression of CYP2D6 activity. To date, however, no clinical study has demonstrated the clinical relevance. Here, the VEN pharmacokinetics at a single dose of VEN with or without co-administration of ZJP was compared. ZJP had a weak herb-drug interactions (HDI) on the pharmacokinetics of VEN. The geometric means of Cmax and AUC0-∞ of VEN increased by 36.7% and 34.6%, respectively, and the corresponding 90% confidence intervals (CIs) of geometric mean ratios (GMRs) exceed outside bioequivalent range of 0.80-1.25. However, the corresponding 90% CIs of GMRs of these parameters for ODV were within the range. Since ODV exposure (AUC), approximately 3.4-fold higher than that of VEN, hardly changed, the systemic exposure of VEN active moiety (VEN + ODV) with ZJP increased slightly (≤8.5%) compared with that of VEN alone. In addition, the incidence of VEN-related side effects, especially gastrointestinal relevance, was significantly reduced with ZJP. Therefore, rational concomitant use of VEN and ZJP might have low risk of HDI and be promising in clinical practice.

Venlafaxine-induced damage to seminiferous epithelium, spermiation, and sperm parameters in rats: A correlation with high estrogen levels.

BACKGROUND: Venlafaxine (selective serotonin and norepinephrine reuptake inhibitor) use has increased worldwide. However, the impact of venlafaxine on testes and sperm parameters has not been investigated. OBJECTIVES: We evaluated venlafaxine impact on testicular and sperm parameters and verified whether the changes are reversible. METHODS: Animals from venlafaxine-35 days and venlafaxine-65 days groups received 30 mg/kg of venlafaxine for 35 days. Control-35 days and control-65 days received distilled water. In control-65 days and venlafaxine-65 days, the treatment was interrupted for 30 days. Sperm concentration, morphology, motility, and mitochondrial activity were analyzed. Number of step 19 spermatids (NLS), frequency of tubules with spermiation failure, Sertoli cells number, and TUNEL-positive germ cells were quantified. Testicular aromatase, connexin 43 (Cx43) immunoexpression, Cx43 protein levels, and Cx43 expression were evaluated. Either intratesticular testosterone or estrogen levels were measured. RESULTS: Venlafaxine impaired sperm morphology, reduced sperm concentration, mitochondrial activity, and sperm motility. The frequency of tubules with spermiation failure and NLS increased in parallel to increased Cx43 immunoexpression; mRNA and protein levels; and aromatase, testosterone, and estrogen levels. An increase in germ cell death and decreased Sertoli cells number were observed. In venlafaxine-65 days, except for sperm motility, mitochondrial activity, Sertoli cells number, and germ cell death, all other parameters were partially or totally recovered. CONCLUSION: Venlafaxine increases testosterone aromatization and Cx43. This drug, via high estrogen levels, disturbs Sertoli cells, induces germ cell death, and impairs spermiation and sperm parameters. The restoration of spermiation associated with the decreased Cx43 and hormonal levels in venlafaxine-65 days reinforces that high estrogen levels are related to venlafaxine-induced changes. The presence of damaged Sertoli cells, germ cell death, and low sperm motility in venlafaxine-65 days indicates that interruption of treatment for 30 days was insufficient for testicular recovery and points to a long-term estrogen impact on the seminiferous epithelium.