SSRI Antidepressants: Patients’ Expectations Influence its Efficacy


Selective serotonin reuptake inhibitors (SSRIs) are widely prescribed anti-depression drugs. However, the superiority over placebo is questioned which in turn is a topic of debate among the clinicians and researchers. The researchers from Uppsala University reported that the way of the treatment description to the patients is important as the treatment itself.

The researchers and the clinicians reported that the SSRIs might lack specific therapeutic properties. The better effects of the drugs were observed using the different expectancies in the drug and placebo groups.

In a double-blind study, the individuals could identify the drug and placebo. Besides, the side effects experienced were easily identified which in turn result in increased expectations of improvement and a beneficial effect. However, the clinical effect of SSRIs influenced by the patient’s expectancies induced by the information patients are given at prescription is unclear.

The beneficial effects of SSRI, escitalopram when given with correct and incorrect verbal information were compared in a study. A team of researchers at Uppsala University's Department of Psychology demonstrated the differences and is published in EBio Medicine.

In the randomized study, all patients with depression were treated with escitalopram for two months. While one group was informed about the drug’s efficacy, the other group was led to believe that they were treated with an 'active placebo' having similar side effects as the SSRI but no beneficial effects.

Vanda Faria reported that the outcomes show that number of responders was three times higher when correct information was provided. The results were compared with an ineffective active placebo, although an identical pharmacological drug was given. 

With the aid of MR Neuroimaging, the differences in the effects of the SSRIs on the brain activity associated with expectations of improvement were identified. The activation of the posterior cingulate cortex and the coupling between this region and the amygdala (central to fear and anxiety) varied in both the groups.

Malin Gingnell said that the outcomes reflect an interaction between cognition and emotion as the brain changes differently with medication depending on the patient's expectancies.

The findings highlight the importance of the communication amongst the physician and the patient. The placebo component related to expectancies in SSRI treatment was suggested.