Change search
ReferencesLink to record
Permanent link

Direct link
Orgasm, Serotonin Reuptake Inhibition, and Plasma Oxytocin in Obsessive-Compulsive Disorder. Gleaning From a Distant Randomized Clinical Trial
Örebro University, School of Health Sciences. University Health Care Research Center, Örebro, Sweden.ORCID iD: 0000-0001-6726-7787
Örebro University, School of Medical Sciences. University Health Care Research Center, Örebro, Sweden.ORCID iD: 0000-0002-3587-6075
2016 (English)In: Sexual medicine, ISSN 2050-1161, Vol. 4, no 3, e145-e155 p.Article in journal (Refereed) Published
Abstract [en]

Introduction: Serotonin reuptake inhibitors (SRIs) are widely used for the treatment of psychiatric disorders, including obsessive-compulsive disorder (OCD). SRIs commonly cause delayed orgasm, the mechanism of which is poorly understood. Oxytocin is involved in sexual function and is interconnected with serotonin within the brain. SRIs are reported to affect the oxytocin system, but possible relations between SRI-induced changes of sexual function and oxytocin are unexplored in humans. In a randomized, double-blinded, placebo-controlled trial of OCD, the anti-obsessive efficacy and adverse events of SRIs and oxytocin measurements were studied.

Aims: To identify possible correlates between oxytocin levels and sexual function; find out whether sexual side effects correlate with levels of oxytocin and/or paroxetine and clomipramine; and test whether changes in sexual functioning are related to an anti-obsessive response.

Methods Reported sexual function and oxytocin plasma levels at rest were studied in 31 adults (15 men and 16 women) with OCD who participated in a randomized, double-blinded trial comparing the SRIs clomipramine and paroxetine with placebo. Sexual adverse effects were quantified by a clinician-administered semistructured interview. Anti-obsessive response was based on the Yale-Brown Obsessive-Compulsive Scale.

Main outcome measures: Ratings on the Sexual Symptom Checklist, plasma oxytocin, serum paroxetine and clomipramine levels, and Yale-Brown Obsessive-Compulsive Scale scores.

RESULTS: Baseline oxytocin levels were positively correlated with baseline OCD severity, but not with sexual functioning. Impaired orgasm at week 6 was reported by 73% of SRI-treated and 20% of placebo-treated patients (P = .03). Impaired orgasm was related to higher oxytocin levels after 4 weeks of SRI treatment (P < .01) but not to SRI concentrations. In men, an association between impaired orgasm and anti-obsessive treatment response was found (P = .028).

CONCLUSION: This pilot study suggests that some collateral effects of SRIs, particularly delayed orgasm, might be influenced by changes within the oxytocinergic system and are related to anti-obsessive mechanisms. Early-onset delayed orgasm in SRI-treated patients could serve as a predictor for OCD treatment response.

Place, publisher, year, edition, pages
Oxford, United Kingdom: Elsevier, 2016. Vol. 4, no 3, e145-e155 p.
Keyword [en]
Adverse effects, clomipramine, obsessive-compulsive disorder, oxytocin/plasma, paroxetine, randomized controlled trial, response prediction, serotonin, serotonin uptake Inhibitors, sexual physiolology
National Category
URN: urn:nbn:se:oru:diva-50976DOI: 10.1016/j.esxm.2016.04.002PubMedID: 27320409OAI: diva2:940556
Available from: 2016-06-21 Created: 2016-06-21 Last updated: 2016-09-06Bibliographically approved
In thesis
1. Obsessive-compulsive disorder, serotonin and oxytocin: treatment response and side effects
Open this publication in new window or tab >>Obsessive-compulsive disorder, serotonin and oxytocin: treatment response and side effects
2016 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

Obsessive-compulsive disorder (OCD), with a prevalence of 1-2 %, frequently leads a chronic course. Persons with OCD are often reluctant to seek help and, if they do, their OCD is often missed. This is unfortunate, since active treatment may substantially improve social function and quality of life. Serotonin reuptake inhibitors (SRIs) have welldocumented efficacy in OCD, but delayed response may be problematic. Methods to predict response have been lacking. Because SRIs are effective, pathophysiological research on OCD has focussed on serotonin. However, no clear aberrations of serotonin have been found, thus other mechanisms ought to be involved.

Our aims were to facilitate clinical detection and assessment of OCD, to search for biochemical correlates of response and side-effects in SRI treatment of OCD and to identify any possible involvement of oxytocin in the pathophysiology of OCD.

In study I, we tested in 402 psychiatric out-patients the psychometric properties of a concise rating scale, “Brief Obsessive Compulsive Scale” (BOCS). BOCS was shown to be easy to use and have excellent discriminant validity in relation to other common psychiatric diagnoses.

Studies II-V were based on 36 OCD patients from a randomised controlled trial of paroxetine, clomipramine or placebo. In study II, contrary to expectation, we found that the change (decrease) of serotonin in whole blood was most pronounced in non-responders to SRI. This is likely to reflect inflammatory influence on platelet turnover rather than serotonergic processes within the central nervous system.

In studies IV-V, we found relations between changes of oxytocin in plasma and the anti-obsessive response, and between oxytocin and the SRI related delay of orgasm, respectively. In both cases, the relation to central oxytocinergic mechanisms is unclear. In males, delayed orgasm predicted anti-obsessive response.

Place, publisher, year, edition, pages
Örebro: Örebro university, 2016. 133 p.
Örebro Studies in Medicine, ISSN 1652-4063 ; 148
Adverse effects, Obsessive-compulsive disorder, Orgasm, Oxytocin, Randomised controlled trial, Rating scale, Response prediction, Serotonin, Serotonin uptake inhibitors, Sexual function
National Category
Psychiatry Family Medicine
Research subject
urn:nbn:se:oru:diva-51438 (URN)978-91-7529-153-6 (ISBN)
Public defence
2016-09-26, Campus USÖ, hörsal C3, Södra Grev Rosengatan, Örebro, 13:00 (Swedish)
Available from: 2016-07-25 Created: 2016-07-25 Last updated: 2016-09-05Bibliographically approved

Open Access in DiVA

Orgasm, Serotonin Reuptake Inhibition, and Plasma Oxytocin in Obsessive-Compulsive Disorder. Gleaning From a Distant Randomized Clinical Trial(1167 kB)4 downloads
File information
File name FULLTEXT01.pdfFile size 1167 kBChecksum SHA-512
Type fulltextMimetype application/pdf

Other links

Publisher's full textPubMed

Search in DiVA

By author/editor
Humble, Mats B.Bejerot, Susanne
By organisation
School of Health SciencesSchool of Medical Sciences

Search outside of DiVA

GoogleGoogle Scholar
Total: 4 downloads
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

Altmetric score

Total: 94 hits
ReferencesLink to record
Permanent link

Direct link