What is a common side effect associated with SSRIs such as sertraline?

Selective serotonin reuptake inhibitors (SSRIs) like sertraline are widely used to treat depression and anxiety disorders. A common and notable side effect associated with SSRIs is gastrointestinal disturbance. This can manifest as nausea, diarrhea, constipation, or other digestive issues. These symptoms often occur when a person first begins taking the medication, as the body adjusts to the increased levels of serotonin in the brain, which in turn affects the gastrointestinal system due to serotonin's influence on gut motility and function.

While weight gain can occur in some individuals taking SSRIs, it is not as consistently reported or immediate as gastrointestinal disturbances. Hypotension and arrhythmias are less common side effects associated with this class of medications. Therefore, gastrointestinal disturbances are recognized as a common side effect, making it the correct answer in this context.