Adverse effects
In September 2016, the US Food and Drug Administration (FDA) required a new warning to be added to the prescribing information related to a link between vilazodone and acute pancreatitis and sleep paralysis.[20] In addition, other sleep disturbances such as hypnagogic hallucinations and sleep terrors can occur.[21][22]
Sleep paralysis is a state, during waking up or falling asleep, in which a person is conscious but experiences full-body paralysis. During an episode, the person may hallucinate (hear, feel, or see things that are not there), which often results in fear.[23] A night terror, also called sleep terror, is a sleep disorder causing feelings of panic or dread.[24] The rate of sleep paralysis adverse events was high enough to merit an FDA warning added to the Viibryd prescription label.[5][21]
In July 2021, the US Food and Drug Administration required a new warning to be added to the prescription label that vilazodone may cause sexual dysfunction. Per the FDA label, sexual dysfunction can include ejaculatory delay or failure, decreased libido, and erectile dysfunction in male patients. In female patients, sexual dysfunction can include decreased libido and delayed or absent orgasm.[5]
The most common adverse effects include nausea, diarrhea, vomiting, and insomnia.[4]
After a one-year, open-label study assessing the safety and tolerability of vilazodone in people with major depressive disorder, the most common adverse effects were diarrhea (35.7%), nausea (31.6%), and headache (20.0%); greater than 90% of these adverse effects were mild or moderate.[25][15] In randomized controlled trials, meanwhile, these rates were 28%, 23.4% and 13.3%, respectively.[15] In contrast to other selective serotonin reuptake inhibitors (SSRIs), initial trials showed that vilazodone did not cause decreased sexual desire/function, which often cause people to abandon their use.[26] However, post-marketing experience led the FDA to warn that vilazodone may cause sexual dysfunction.[5]
Pregnancy
Antidepressant exposure (including vilazodone) is associated with shorter average duration of pregnancy (by three days), increased risk of preterm delivery (by 55%), lower birth weight (by 75 g), and lower Apgar scores (by <0.4 points).[27][28] It is uncertain whether there is an increased rate of septal heart defects among children whose mothers were prescribed an SSRI in early pregnancy.[29][30]
