A groundbreaking study from the University of Copenhagen has revealed a method to predict which patients are likely to experience sexual dysfunction as a side effect of antidepressants. This research is particularly relevant given that millions of people in the UK are prescribed antidepressants annually, and many suffer from sexual side effects that can negatively impact their quality of life.
Selective serotonin reuptake inhibitors (SSRIs), a common class of antidepressants, are known to cause issues such as reduced libido, difficulty achieving or maintaining erections, and challenges with orgasm. These side effects can exacerbate feelings of depression, leading some patients to discontinue their medication.
The research team focused on identifying patients at risk of SSRI-related sexual dysfunction prior to treatment. They studied a group of 90 adults aged between 18 and 56 diagnosed with major depressive disorder. None of the participants were on medication at the time of the study, which comprised 66 women and 24 men. Each subject underwent an electroencephalogram (EEG) to measure serotonin levels in their brains before initiating treatment with escitalopram, marketed as Cipralex in the UK, over an eight-week period.
Researchers monitored changes in sexual function throughout the treatment. They found that sexual side effects are prevalent, with up to 40–70 percent of patients reporting issues such as decreased desire, arousal, and orgasm capabilities. In their report published in the Journal of Psychiatric Research, the researchers noted that these side effects significantly impact patients’ quality of life, self-esteem, and interpersonal relationships, often contributing to medication non-adherence.
At the conclusion of the study, findings indicated that participants with higher serotonin levels were more prone to developing sexual side effects, particularly difficulties with orgasm. Approximately 65 percent of patients reported experiencing some form of sexual dysfunction linked to the medication, with 39 percent classifying these issues as distressing. Assessments showed that 47 percent of patients experienced sexual side effects from the SSRIs, with 17 percent (nine women and four men) reporting severe distress due to these effects. Overall, sexual function declined by nearly 23 percent across the group.
Despite the promising findings, the researchers acknowledged limitations in the study. They pointed out that women often exhibit sexual dysfunction prior to starting antidepressant therapy, whereas men typically do not. Additionally, the participant pool was skewed toward women, which may affect the generalizability of the results.
The study’s implications extend to the ongoing discourse surrounding post-SSRI sexual dysfunction (PSSD), a rare and controversial condition that some claim leads to long-term sexual issues after discontinuing SSRIs. Although not officially recognized by the NHS, there is growing advocacy for further research into PSSD. A review by European Psychiatry suggests that there is increasing evidence supporting the existence of this condition, despite limited research on its long-term effects.
An early investigation published in the Annals of General Psychiatry estimated that 1 in 216 patients may experience erectile dysfunction following SSRI cessation. The PSSD Network reports symptoms including genital numbness, erectile dysfunction, vaginal dryness, and complete loss of libido.
The NHS acknowledges that sexual side effects can occur during SSRI treatment. Recent statistics indicate that 286,799 individuals aged five to 19 were prescribed antidepressants in 2024, a significant increase from 242,629 in 2016. Common SSRIs include citalopram, fluoxetine, and sertraline, known by brand names such as Cipramil, Prozac, and Lustral.
As research continues, the hope is that healthcare providers will consider individual serotonin levels when prescribing SSRIs, potentially minimizing the risk of distressing sexual side effects and improving overall patient outcomes.
