Scientists have found that problems like trouble having an erection or reaching orgasm during antidepressant treatment may be linked to serotonin levels in the brain—but only in people with depression who are taking a certain kind of antidepressant called SSRIs.
This discovery could help doctors choose the right medication for each patient, especially for those concerned about sexual side effects. The study was presented at the European College of Neuropsychopharmacology (ECNP) conference in Amsterdam.
Sexual problems are common for people with depression. SSRIs (like Prozac or escitalopram) are often prescribed to improve mood. However, while they can help treat depression, they often cause sexual side effects themselves.
These side effects—like reduced desire, trouble getting or maintaining an erection, and delayed orgasm—can affect up to 70% of people taking SSRIs and may cause people to stop taking their medication.
Right now, there is no way to know in advance who will experience these issues. But a team of researchers in Copenhagen may have found a way to predict this.
They studied 90 people diagnosed with depression. Before treatment began, the researchers measured brain serotonin activity using a test called LDAEP (Loudness Dependence of Auditory Evoked Potentials).
This is a simple, non-invasive hearing test that involves listening to sounds at different volumes while brain activity is recorded. Interestingly, this test can also indicate serotonin levels in the brain—the lower the LDAEP score, the higher the serotonin activity.
After the test, all the participants started an 8-week course of SSRI antidepressants. The researchers closely tracked their sexual health throughout the treatment. They found that people who had higher serotonin activity before starting the medication were much more likely to develop sexual side effects—especially trouble reaching orgasm.
Dr. Kristian Jensen, the lead researcher from Copenhagen University Hospital, said that using the LDAEP brain scan and information about a person’s sexual history, they could predict orgasm problems with 87% accuracy. He noted that more research is needed to accurately measure the risk of erectile dysfunction, especially in men.
This early prediction could help patients avoid the distress of unwanted side effects. If the results are confirmed in larger studies, doctors could use the LDAEP test to pick medications with fewer sexual side effects for each person.
Dr. Jensen explained that the test only applies to medication-caused sexual problems. It is not useful for diagnosing general sexual difficulties, but they are already working on a larger study with 600 participants to look at how serotonin and sex hormone levels affect sexual function during depression and treatment.
Professor Eric Ruhe, an expert on treatment-resistant depression from Radboudumc in the Netherlands, praised the study. He called it “a very interesting study” that could help predict whether someone will experience sexual problems from antidepressants.
He added that this type of testing could help patients who are hesitant to start treatment because they fear these side effects. He also encouraged more work to develop tools that not only predict side effects but also suggest better medication choices.
This research is still under peer review, and more studies are needed. The participants in the current study were mostly young (average age 27) and mostly female (73%), so it will be important to see if the results apply to a broader population.
Dr. Jensen described the LDAEP test as simple and elegant. “We play sounds through headphones at different volumes and measure brain waves. The whole test takes about 30 minutes and is completely non-invasive,” he said. While the test isn’t widely available yet, that may change if future studies confirm its usefulness.
If you care about mental health, please read studies about cannabis use disorder linked to increased risk of mental diseases and some mental health drugs can cause rapid weight gain.
For more health information, please read studies that one sleepless night can reverse depression for days and scientists find better treatment for older adults with depression.
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