Pharmacological interventions for antipsychotic-related sialorrhea: a systematic review and network meta-analysis of randomized trials.

Antipsychotic-induced sialorrhea carries a significant burden, but evidence-based treatment guidance is incomplete, warranting network meta-analysis (NMA) of pharmacological interventions for antipsychotic-related sialorrhea. PubMed Central/PsycInfo/Cochrane Central database/Clinicaltrials.gov/WHO-ICTRP and the Chinese Electronic Journal Database (Qikan.cqvip.com) were searched for published/unpublished RCTs of antipsychotic-induced sialorrhea (any definition) in adults, up to 06/12/2023. We assessed global/local inconsistencies, publication bias, risk of bias (RoB2), and confidence in the evidence, conducting subgroup/sensitivity analyses. Co-primary efficacy outcomes were changes in saliva production (standardized mean difference/SMD) and study-defined response (risk ratios/RRs). The acceptability outcome was all-cause discontinuation (RR). Primary nodes were molecules; the mechanism of action (MoA) was secondary. Thirty-four RCTs entered a systematic review, 33 NMA (n = 1958). All interventions were for clozapine-induced sialorrhea in subjects with mental disorders. Regarding individual agents and response, metoclopramide (RR = 3.11, 95% C.I. = 1.39-6.98), cyproheptadine, (RR = 2.76, 95% C.I. = 2.00-3.82), sulpiride (RR = 2.49, 95% C.I. = 1.65-3.77), propantheline (RR = 2.39, 95% C.I. = 1.97-2.90), diphenhydramine (RR = 2.32, 95% C.I. = 1.88-2.86), benzhexol (RR = 2.32, 95% C.I. = 1.59-3.38), doxepin (RR = 2.30, 95% C.I. = 1.85-2.88), amisulpride (RR = 2.23, 95% C.I. = 1.30-3.81), chlorpheniramine (RR = 2.20, 95% C.I. = 1.67-2.89), amitriptyline (RR = 2.09, 95% C.I. = 1.34-3.26), atropine, (RR = 2.03, 95% C.I. = 1.22-3.38), and astemizole, (RR = 1.70, 95% C.I. = 1.28-2.26) outperformed placebo, but not glycopyrrolate or ipratropium. Across secondary nodes (k = 28, n = 1821), antimuscarinics (RR = 2.26, 95% C.I. = 1.91-2.68), benzamides (RR = 2.23, 95% C.I. = 1.75-3.10), TCAs (RR = 2.23, 95% C.I. = 1.83-2.72), and antihistamines (RR = 2.18, 95% C.I. = 1.83-2.59) outperformed placebo. In head-to-head comparisons, astemizole and ipratropium were outperformed by several interventions. All secondary nodes, except benzamides, outperformed the placebo on the continuous efficacy outcome. For nocturnal sialorrhea, neither benzamides nor atropine outperformed the placebo. Active interventions did not differ significantly from placebo regarding constipation or sleepiness/drowsiness. Low-confidence findings prompt caution in the interpretation of the results. Considering primary nodes' co-primary efficacy outcomes and head-to-head comparisons, efficacy for sialorrhea is most consistent for the following agents, decreasing from metoclopramide through cyproheptadine, sulpiride, propantheline, diphenhydramine, benzhexol, doxepin, amisulpride, chlorpheniramine, to amitriptyline, and atropine (the latter not for nocturnal sialorrhea). Shared decision-making with the patient should guide treatment decisions regarding clozapine-related sialorrhea.

Comparison of gabapentin and doxepin in the management of uremic pruritus: A randomized crossover clinical trial.

Gabapentin and doxepin are well-known treatments of uremic pruritus in hemodialysis patients but no head-to-head studies were conducted to date. The aim of this trial is to compare the efficacy and the tolerability of gabapentin and doxepin in the treatment of uremic pruritus in hemodialysis patients. A single-blind crossover randomized trial was conducted that included hemodialysis patients with uremic pruritus. Patients were randomized to receive 10 mg doxepin daily or 100 mg gabapentin for 4 weeks and the two groups were treated conversely for another 4 weeks after a 4-week washout period. Eighty-five patients were screened for eligibility. Thirty-one met the inclusion criteria and four were excluded. Sixteen patients agreed and signed the consent and two withdrew from the study. VAS scores at baseline were 6.71 and 6.14, and dropped to 0.57 and 2.35 at week 4 in the gabapentin and doxepin groups, respectively. Mean scores of the 5-Domain Itch Scale (5-D) at baseline were 14.71 and 14.64, and dropped to 5.78 and 7.57 at week 4 in the gabapentin and doxepin groups, respectively. Mean scores of the Dermatology Life Quality Index (DLQI) at baseline were 9.6429 and 8.7857, and dropped to 0.71 and 3.35 at week 4 in the gabapentin and doxepin groups, respectively. Reductions in Visual Analog Scale (VAS), 5-D and DLQI were statistically significant (P < .05). No serious side effects were recorded. Limitations of this study include single-blind design, small number of included cases and lack of placebo control. Gabapentin was more effective than doxepin in decreasing uremic pruritus severity and improving quality of life of these patients.

Nortriptyline serum concentration as a predictor for cardiac risk in amitriptyline-treated patients.

PURPOSE: Tricyclic antidepressants have been shown to affect electrocardiogram (ECG) parameters, but there is limited evidence in relation to the serum concentrations. Therefore, we aimed to evaluate a prediction of cardiac risk in amitriptyline- and doxepin-treated patients by serum concentrations. PATIENTS AND METHODS: The association between serum concentrations of amitriptyline (n = 100) and doxepin (n = 71) and ECG parameters was retrospectively examined using linear regression analysis. Mann-Whitney U tests were applied to evaluate differences in QTc intervals in patients with serum concentrations above and below the upper limit of the therapeutic reference range, as well as the alert level of each target drug. RESULTS: The sum serum concentration of amitriptyline and the nortriptyline serum concentration were significantly associated with an increased PQ interval (p = 0.020, p = 0.007), as well as with increased QTcB (p = 0.012, p < 0.001) and QTcF intervals (p = 0.025, p < 0.001). The nortriptyline concentration was significantly associated with the QRS interval (p = 0.003). In patients with active moiety concentrations above the alert level (300 ng/ml) and nortriptyline concentrations above the reference range (170 ng/ml), the QTcB interval was significantly prolonged (p = 0.032, p = 0.007). No significant association with any ECG parameter was detected for doxepin serum concentrations. CONCLUSION: The effect of amitriptyline on ECG parameters may be explained by nortriptyline alone. Accordingly, with increasing nortriptyline concentrations, the potential risk for an atrioventricular block, a bundle branch block, and prolongation of QTc interval may increase significantly.

Doxepin in difficult-to-treat chronic urticaria: A retrospective, cross-sectional study from Turkey.

Doxepin is an old tricyclic antidepressant, whose efficacy in chronic urticaria had been well documented until 1990. However, over the past three decades, there has been limited data on its use. We aimed to assess the efficacy and safety of doxepin in the treatment of patients with chronic urticaria who were poorly responsive to antihistamines. In this retrospective, cross-sectional, single-center study from Turkey, data were examined from patients with chronic urticaria who had poor antihistamine responses and received doxepin therapy from 1998 to 2017. Patient data were analyzed with regard to the duration of the disease, age, sex, treatment outcomes using a weekly urticaria activity score (UAS7), and adverse effects of doxepin therapy. A reduction of ≥90% in UAS7 was defined as "complete response," 30-89% as "partial response" and <30% as "no significant response." Thirty-six patients were included in this study. Doxepin was effective in a majority (n = 27, 75%) of the patients with a short onset time. Sixteen patients (44.4%) showed a complete response. Mild sedative and anticholinergic side effects were well tolerated. Doxepin seems to be a reasonable, efficient, and affordable alternative for the treatment of chronic urticaria in patients who respond poorly to antihistamine therapy.

Effect of Doxepin Mouthwash or Diphenhydramine-Lidocaine-Antacid Mouthwash vs Placebo on Radiotherapy-Related Oral Mucositis Pain: The Alliance A221304 Randomized Clinical Trial.

Importance: Oral mucositis causes substantial morbidity during head and neck radiotherapy. In a randomized study, doxepin mouthwash was shown to reduce oral mucositis-related pain. A common mouthwash comprising diphenhydramine-lidocaine-antacid is also widely used. Objective: To evaluate the effect of doxepin mouthwash or diphenhydramine-lidocaine-antacid mouthwash for the treatment of oral mucositis-related pain. Design, Setting, and Participants: A phase 3 randomized trial was conducted from November 1, 2014, to May 16, 2016, at 30 US institutions and included 275 patients who underwent definitive head and neck radiotherapy, had an oral mucositis pain score of 4 points or greater (scale, 0-10), and were followed up for a maximum of 28 days. Interventions: Ninety-two patients were randomized to doxepin mouthwash (25 mg/5 mL water); 91 patients to diphenhydramine-lidocaine-antacid; and 92 patients to placebo. Main Outcome and Measures: The primary end point was total oral mucositis pain reduction (defined by the area under the curve and adjusted for baseline pain score) during the 4 hours after a single dose of doxepin mouthwash or diphenhydramine-lidocaine-antacid mouthwash compared with a single dose of placebo. The minimal clinically important difference was a 3.5-point change. The secondary end points included drowsiness, unpleasant taste, and stinging or burning. All scales ranged from 0 (best) to 10 (worst). Results: Among the 275 patients randomized (median age, 61 years; 58 [21%] women), 227 (83%) completed treatment per protocol. Mucositis pain during the first 4 hours decreased by 11.6 points in the doxepin mouthwash group, by 11.7 points in the diphenhydramine-lidocaine-antacid mouthwash group, and by 8.7 points in the placebo group. The between-group difference was 2.9 points (95% CI, 0.2-6.0; P = .02) for doxepin mouthwash vs placebo and 3.0 points (95% CI, 0.1-5.9; P = .004) for diphenhydramine-lidocaine-antacid mouthwash vs placebo. More drowsiness was reported with doxepin mouthwash vs placebo (by 1.5 points [95% CI, 0-4.0]; P = .03), unpleasant taste (by 1.5 points [95% CI, 0-3.0]; P = .002), and stinging or burning (by 4.0 points [95% CI, 2.5-5.0]; P < .001). Maximum grade 3 adverse events for the doxepin mouthwash occurred in 3 patients (4%); diphenhydramine-lidocaine-antacid mouthwash, 3 (4%); and placebo, 2 (2%). Fatigue was reported by 5 patients (6%) in the doxepin mouthwash group and no patients in the diphenhydramine-lidocaine-antacid mouthwash group. Conclusions and Relevance: Among patients undergoing head and neck radiotherapy, the use of doxepin mouthwash or diphenhydramine-lidocaine-antacid mouthwash vs placebo significantly reduced oral mucositis pain during the first 4 hours after administration; however, the effect size was less than the minimal clinically important difference. Further research is needed to assess longer-term efficacy and safety for both mouthwashes. Trial Registration: ClinicalTrials.gov Identifier: NCT02229539.

Modified biomolecule as potential vehicle for buccal delivery of doxepin.

AIM: Doxepin is a traditional tricyclic antidepressant with analgesic and anesthetic properties when applied topically to the mucosa. Doxepin is one approach in treating insomnia and depression in Parkinson's disease. Patients with Parkinson's disease suffer difficulties in swallowing. Therefore, it was the aim of this study to develop a buccal-adhesive delivery system. METHODS: Pectin was modified with cysteine. Stability assays in form of disintegration assay according to the Ph.Eur were performed. Furthermore, bioadhesiveness on buccal mucosa was investigated incorporating the drug doxepin. RESULTS: The adhesiveness was improved 1.4-fold and revealed a sustained release over 3 h. CONCLUSION: Taking these findings into account, the modifications render this designed excipient fruitful for buccal delivery.

Doxepin for insomnia: a systematic review of randomized placebo-controlled trials.

Doxepin, a sedating tricyclic drug, at 3 mg and 6 mg doses was recently approved by the U.S. food and drug administration (FDA) for the treatment of insomnia. The objective of this systematic review was to obtain a precise summary of the efficacy and safety of doxepin as a hypnotic. We searched key databases and trial registers up to March 2014 and contacted pharmaceutical companies and the FDA for unpublished data. A total of nine randomized placebo-controlled trials were analyzed. Six studies were on doxepin 1-6 mg/d, two on doxepin 25-300 mg/d, and one on ramelteon 8 mg and doxepin 3 mg combined. All low-dose studies were industry-sponsored. We found that low-dose doxepin had a small to medium effect size against placebo for sleep maintenance and sleep duration but not for sleep initiation at both immediate and short-term posttreatment. There was no significant next-day residual effect with low-dose doxepin. Headache and somnolence were the most common side effects. We concluded that low-dose doxepin for 1-2 nights appeared to be safe and effective in improving sleep. However, a clear conclusion on its short-term benefits and risks as well as withdrawal effects was not possible due to the small number of studies.

Doxepin rinse versus placebo in the treatment of acute oral mucositis pain in patients receiving head and neck radiotherapy with or without chemotherapy: a phase III, randomized, double-blind trial (NCCTG-N09C6 [Alliance]).

PURPOSE: Painful oral mucositis (OM) is a significant toxicity during radiotherapy for head and neck cancers. The aim of this randomized, double-blind, placebo-controlled trial was to test the efficacy of doxepin hydrochloride in the reduction of radiotherapy-induced OM pain. PATIENTS AND METHODS: In all, 155 patients were randomly allocated to a doxepin oral rinse or a placebo for the treatment of radiotherapy-related OM pain. Patients received a single dose of doxepin or placebo on day 1 and then crossed over to receive the opposite agent on a subsequent day. Pain questionnaires were administered at baseline and at 5, 15, 30, 60, 120, and 240 minutes. Patients were then given the option to continue doxepin. The primary end point was pain reduction as measured by the area under the curve (AUC) of the pain scale using data from day 1. RESULTS: Primary end point analysis revealed that the AUC for mouth and throat pain reduction was greater for doxepin (-9.1) than for placebo (-4.7; P < .001). Crossover analysis of patients completing both phases confirmed that patients experienced greater mouth and throat pain reduction with doxepin (intrapatient changes of 4.1 for doxepin-placebo arm and -2.8 for placebo-doxepin arm; P < .001). Doxepin was associated with more stinging or burning, unpleasant taste, and greater drowsiness than the placebo rinse. More patients receiving doxepin expressed a desire to continue treatment than did patients with placebo after completion of each of the randomized phases of the study. CONCLUSION: A doxepin rinse diminishes OM pain. Further studies are warranted to determine its role in the management of OM.

Interaction of valproic acid and the antidepressant drugs doxepin and venlafaxine: analysis of therapeutic drug monitoring data under naturalistic conditions.

Valproic acid and the antidepressants doxepin and venlafaxine are frequently used psychotropic drugs. In the literature, an influence of valproic acid on serum levels of antidepressants has been described, although studies have focused on amitriptyline. The authors assessed their therapeutic drug monitoring (TDM) database for patients receiving a combination of doxepin or venlafaxine and valproic acid and compared these samples with matched controls without valproic acid comedication in terms of the serum concentration of antidepressants. The mean dose-corrected serum concentration of doxepin+N-doxepin in 16 patients who received valproic acid comedication was higher (2.171±1.482 ng/ml/mg) than that in the matched controls (0.971±0.857 ng/ml/mg, P<0.003). We also found a significant correlation between valproic acid serum level and dose-corrected doxepin+N-doxepin serum level (Spearman's ρ r=0.602, P<0.014). The mean dose-corrected serum level of venlafaxine+O-desmethylvenlafaxine in 41 patients who received valproic acid comedication did not differ significantly from that of the matched controls (P<0.089), but there was a significant difference between both groups in the dose-corrected serum level of O-desmethylvenlafaxine (1.403±0.665 vs. 1.102±0.444, P<0.017). As a consequence, if a combination of valproic acid with doxepin or venlafaxine is administered, cautious dosing is advisable and TDM should be performed.

QT interval prolongation and torsades de pointes in a patient undergoing treatment with vorinostat: a case report and review of the literature.

Vorinostat is a histone deacetylase inhibitor used in the treatment of recurrent or persistent cases of cutaneous T-cell lymphoma (CTCL). A retrospective review of 116 patients from phase I and II clinical trials who had a baseline and at least one subsequent ECG revealed that four patients had Grade 2 and one patient had Grade 3 QTc interval prolongation; however, a MEDLINE search found no reported cases of torsades de pointes (TdP) in patients treated with vorinostat. We describe the case of a 49 year-old male with a history of CTCL actively undergoing treatment with vorinostat. During day 1 of hospitalization, he developed a pulseless polymorphic ventricular tachycardia requiring resuscitation. He was found to have a QTc of 826 ms. Following correction of potassium and magnesium, QTc gradually decreased and no further ventricular arrhythmia was noted. Other factors implicated in this case included concurrent sertraline and doxepin therapy (both drugs have been associated with the development of TdP in overdose). The mechanism of development of TdP in this patient is postulated to be related to vorinostat use in combination with hypokalemia and concomitant treatment with medications associated with QTc prolongation. This case highlights the importance of post-market surveillance.

Efficacy and safety of doxepin 6 mg in a four-week outpatient trial of elderly adults with chronic primary insomnia.

INTRODUCTION: The efficacy and safety of doxepin (DXP), a histamine H(1) receptor antagonist, was evaluated in elderly adults with sleep maintenance insomnia. METHODS: This was a randomized, double-blind, placebo-controlled outpatient trial. Elderly adults meeting DSM-IV-TR criteria for primary insomnia were randomized to four weeks of nightly treatment with either DXP 6 mg (N=130) or placebo (PBO; N=124). Efficacy was assessed using patient self-report instruments and clinician ratings. Patient-reported endpoints included subjective total sleep time (sTST), subjective wake after sleep onset (sWASO), latency to sleep onset (LSO), sleep quality, and a Patient Global Impression scale (PGI). The primary endpoint was sTST at week 1. RESULTS: DXP 6 mg produced significantly more sTST and less sWASO at week 1 (both p-values <0.0001) than PBO. These significant improvements versus placebo were maintained at weeks 2-4 (all p-values <0.05). There were no significant differences in LSO for DXP 6 mg versus PBO. DXP 6 mg significantly improved sleep quality (weeks 1, 3, and 4, p<0.05) and several outcome-related parameters, including several items on the PGI, the severity and improvement items of the Clinician Global Impression scale (CGI; weeks 1 and 2) and the Insomnia Severity Index (ISI; weeks 1-4), all versus PBO. There were no reports of anticholinergic effects (e.g., dry mouth) or memory impairment. The safety profile of DXP 6 mg was comparable to that of PBO. CONCLUSIONS: In elderly adults with insomnia, DXP 6 mg produced significant improvements in sleep maintenance, sleep duration, and sleep quality endpoints that were sustained throughout the trial. These data suggest that DXP 6 mg is effective for treating sleep maintenance insomnia and is well-tolerated in elderly adults with chronic primary insomnia.

Efficacy and safety of doxepin 3 and 6 mg in a 35-day sleep laboratory trial in adults with chronic primary insomnia.

STUDY OBJECTIVES: To evaluate the efficacy and safety of doxepin (DXP) 3 mg and 6 mg in adults diagnosed with primary insomnia. DESIGN AND METHODS: The study was a randomized, double-blind, parallel-group, placebo-controlled trial. Patients meeting DSM-IV-TR criteria for primary insomnia were randomized to 35 days of nightly treatment with DXP 3 mg (n=75), DXP 6 mg (n=73), or placebo (PBO; n=73), followed by 2 nights of single-blind PBO to evaluate discontinuation (DC) effects. Efficacy was assessed using polysomnography (PSG) and patient reports. Efficacy data were examined for Night (N) 1, N15, and N29. Safety assessments were conducted throughout the study. RESULTS: Compared with PBO, DXP 3 and 6 mg significantly improved wake time after sleep onset (WASO) on N1 (3 mg and 6 mg; P<0.0001), N15 (3 mg P=0.0025; 6 mg P=0.0009), and N29 (3 mg P=0.0248; 6 mg P=0.0009), latency to persistent sleep (LPS) on N1 (3 mg P=0.0047; 6 mg P=0.0007), and total sleep time (TST) on N1 (3 mg and 6 mg P<0.0001), N15 (6 mg P=0.0035), and N29 (3 mg P=0.0261; 6 mg P<0.0001). In terms of early morning awakenings, DXP 3 and 6 mg demonstrated significant improvements in SE in the final quarter of the night on N1, N15, and N29, with the exception of 3 mg on N29 (P=0.0691). Rates of discontinuation were low, and the safety profiles were comparable across the 3 treatment groups. There were no significant next-day residual effects, and there were no spontaneous reports of memory impairment, complex sleep behaviors, anticholinergic effects, weight gain, or increased appetite. Additionally, there was no evidence of rebound insomnia after DXP discontinuation. CONCLUSIONS: Five weeks of nightly administration of DXP 3 mg and 6 mg to adults with chronic primary insomnia resulted in significant and sustained improvements in sleep maintenance and early morning awakenings (with the exception of SE in the final quarter of the night on N29 for 3 mg [P=0.0691]). These sleep improvements were not accompanied by next-day residual effects or followed by rebound insomnia or withdrawal effects upon discontinuation. These findings confirm the unique profile of sleep maintenance efficacy and safety of DXP observed in prior studies.

A placebo- and active-controlled assessment of 6- and 50-mg oral doxepin on cardiac repolarization in healthy volunteers: a thorough QT evaluation.

BACKGROUND: Doxepin tablets have recently been approved in the United States in doses of 3 and 6 mg for the treatment of insomnia characterized by difficulty with sleep maintenance. OBJECTIVE: Because no previous thorough QT evaluation of doxepin has been conducted, the primary objective of this study was to assess the highest recommended dose (6 mg) and a supratherapeutic amount (50 mg) of doxepin on cardiac repolarization under steady-state conditions in healthy adult subjects. METHODS: Male and female volunteers aged 18 to 45 years were randomized to receive double-blind doxepin or placebo for 7 days, or 6 days of double-blind placebo before one open-label administration of 400-mg moxifloxacin on day 7. Holter electrocardiograms were collected at baseline and on day 7 for up to 23.5 hours after dosing; the results were read at a central facility. The primary outcome measure was the time-matched change from baseline in individually corrected QT (QTcI) intervals. Additional outcome measures were used to evaluate outlying QTc values and the relationship of QTcI to plasma concentrations of doxepin and its primary demethylated metabolite, nordoxepin. RESULTS: A total of 206 healthy subjects (108 women, 98 men) were randomized to a study group; 192 subjects (93.2%) received all scheduled administrations of study drug, and 190 subjects (92.2%) completed the study. The study population was 47.6% male and 52.4% female, and the mean age was 30.3 years. Neither amount of administered doxepin increased QTcI, nor did the upper bound of the 95% CIs for the point estimates exceed 10 milliseconds at any time point. The results for moxifloxacin met the assay sensitivity criteria for a positive control. The predicted placebo-corrected change in QTcI at the mean doxepin C(max) values for both administered amounts (6 mg: -0.88 millisecond [upper CI: 0.37 millisecond]; 50 mg, 2.38 milliseconds [upper CI: 4.00 milliseconds]) did not suggest an effect on cardiac repolarization, and no doxepin-treated subject met specific criteria for outlying QTc values. CONCLUSION: This thorough QT study revealed no effects of doxepin on QTcI up to 50 mg, suggesting that doxepin therapy for insomnia is unlikely to increase QTc intervals.

Efficacy and Safety of Doxepin 1 mg and 3 mg in a 12-week Sleep Laboratory and Outpatient Trial of Elderly Subjects with Chronic Primary Insomnia.

STUDY OBJECTIVES: to evaluate the efficacy and safety of doxepin 1 mg and 3 mg in elderly subjects with chronic primary insomnia. DESIGN AND METHODS: the study was a randomized, double-blind, parallel-group, placebo-controlled trial. Subjects meeting DSM-IV-TR criteria for primary insomnia were randomized to 12 weeks of nightly treatment with doxepin (DXP) 1 mg (n = 77) or 3 mg (n = 82), or placebo (PBO; n = 81). Efficacy was assessed using polysomnography (PSG), patient reports, and clinician ratings. Objective efficacy data are reported for Nights (N) 1, 29, and 85; subjective efficacy data during Weeks 1, 4, and 12; and Clinical Global Impression (CGI) scale and Patient Global Impression (PGI) scale data after Weeks 2, 4, and 12 of treatment. Safety assessments were conducted throughout the study. RESULTS: DXP 3 mg led to significant improvement versus PBO on N1 in wake time after sleep onset (WASO; P < 0.0001; primary endpoint), total sleep time (TST; P < 0.0001), overall sleep efficiency (SE; P < 0.0001), SE in the last quarter of the night (P < 0.0001), and SE in Hour 8 (P < 0.0001). These improvements were sustained at N85 for all variables, with significance maintained for WASO, TST, overall SE, and SE in the last quarter of the night. DXP 3 mg significantly improved patient-reported latency to sleep onset (Weeks 1, 4, and 12), subjective TST (Weeks 1, 4, and 12), and sleep quality (Weeks 1, 4, and 12). Several global outcome-related variables were significantly improved, including the severity and improvement items of the CGI (Weeks 2, 4, and 12), and all 5 items of the PGI (Week 12; 4 items after Weeks 2 and 4). Significant improvements were observed for DXP 1 mg for several measures including WASO, TST, overall SE, and SE in the last quarter of the night at several time points. Rates of discontinuation were low, and the safety profiles were comparable across the 3 treatment groups. There were no significant next-day residual effects; additionally, there were no reports of memory impairment, complex sleep behaviors, anticholinergic effects, weight gain, or increased appetite. CONCLUSIONS: DXP 1 mg and 3 mg administered nightly to elderly chronic insomnia patients for 12 weeks resulted in significant and sustained improvements in most endpoints. These improvements were not accompanied by evidence of next-day residual sedation or other significant adverse effects. DXP also demonstrated improvements in both patient- and physician-based ratings of global insomnia outcome. The efficacy of DXP at the doses used in this study is noteworthy with respect to sleep maintenance and early morning awakenings given that these are the primary sleep complaints of the elderly. This study, the longest placebo-controlled, double-blind, polysomnographic trial of nightly pharmacotherapy for insomnia in the elderly, provides the best evidence to date of the sustained efficacy and safety of an insomnia medication in older adults.