Trial reportPsychopharmacology2011
Sildenafil adjunctive therapy to risperidone in the treatment of the negative symptoms of schizophrenia: a double-blind randomized placebo-controlled trial.
Trial report in Psychopharmacology, 2011. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 14 papers.
What it found
Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.
The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.
Who cites it
14 citing papers in PubMed, 45 citations in OpenAlex.
- Pentoxifylline adjunct to risperidone for negative symptoms of stable schizophrenia: a randomized, double-blind, placebo-controlled trial.The international journal of neuropsychopharmacology · 2024Trial
- Cilostazol as an adjunctive treatment in major depressive disorder: a pilot randomized, double-blind, and placebo-controlled clinical trial.Psychopharmacology · 2022Trial
- A double-blind, placebo controlled, randomized trial of riluzole as an adjunct to risperidone for treatment of negative symptoms in patients with chronic schizophrenia.Psychopharmacology · 2014Trial
- A placebo-controlled study of tropisetron added to risperidone for the treatment of negative symptoms in chronic and stable schizophrenia.Psychopharmacology · 2013Trial
- Intranasal oxytocin as an adjunct to risperidone in patients with schizophrenia : an 8-week, randomized, double-blind, placebo-controlled study.CNS drugs · 2013Trial
- A placebo-controlled study of the modafinil added to risperidone in chronic schizophrenia.Psychopharmacology · 2012Trial
- In the Brain of Phosphodiesterases: Potential Therapeutic Targets for Schizophrenia.Clinical psychopharmacology and neuroscience : the official scientific journal of the Korean College of Neuropsychopharmacology · 2025Review
- Pharmacological Interventions for Negative Symptoms in Schizophrenia: A Systematic Review of Randomised Control Trials.Biomedicines · 2025Review
- Efficacy and Safety of Phosphodiesterase-5 Inhibitors for Erectile Dysfunction in Schizophrenia: A Systematic Review and Meta-Analysis.Neuropsychiatric disease and treatment · 2025Review
- Therapeutic targeting of 3',5'-cyclic nucleotide phosphodiesterases: inhibition and beyond.Nature reviews. Drug discovery · 2019Review
- Critical role of nitric oxide in the modulation of prepulse inhibition in Swiss mice.Psychopharmacology · 2014Article
- Addressing the unmet needs of patients with persistent negative symptoms of schizophrenia: emerging pharmacological treatment options.Neuropsychiatric disease and treatment · 2014Review
- The PDE5 inhibitor vardenafil does not affect auditory sensory gating in rats and humans.Psychopharmacology · 2013Article
- Re: sildenafil adjunctive therapy to risperidone in the treatment of the negative symptoms of schizophrenia.Psychopharmacology · 2011Article
Corrections and comments
- Commented on by
Authors and funding
11 authors at 5 institutions in 1 country.
Funding
No grant is acknowledged in the PubMed record.
Abstract
rationalIt has been suggested that phosphodiesterase 5 inhibitors such as sildenafil may be effective in the treatment of negative symptoms of schizophrenia.
objectiveThis study was designed to investigate the effect of sildenafil added to risperidone as augmentation therapy in patients with chronic schizophrenia and prominent negative symptoms in a double-blind and randomized clinical trial.
methodsEligible participants in the study were 40 patients with chronic schizophrenia with ages ranging from 18 to 45 years. All patients were inpatients and were in the active phase of the illness and met DSM-IV-TR criteria for schizophrenia. Patients were allocated in a random fashion: 20 to risperidone (6 mg/day) plus sildenafil (75 mg/day) and 20 to risperidone (6 mg/day) plus placebo. The principal measure of outcome was Positive and Negative Syndrome Scale (PANSS).
resultsAlthough both protocols significantly decreased the score of the positive, negative, and general psychopathological symptoms over the trial period, the combination of risperidone and sildenafil showed a significant superiority over risperidone alone in decreasing negative symptoms and PANSS total scores over the 8-week trial (between-subjects factor; F = 4.77, df = 1; P = 0.03; F = 5.91, df = 1, P = 0.02 respectively).
conclusionTherapy with 75 mg/day of sildenafil was well tolerated, and no clinically important side effects were observed. The present study indicates sildenafil as a potential adjunctive treatment strategy for treatment of negative symptoms of schizophrenia. This trial is registered with the Iranian Clinical Trials Registry (IRCT1138901151556N11).
Indexed as
Identifiers
What OpenQuestion holds
Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.