SN educated on medication Escitalopram. This medication is used to treat depression in adults and children and teenagers 12 years or older. Escitalopram is also used to treat generalized anxiety disorder (GAD; excessive worry and tension that disrupts daily life for 6 months or longer) in adults. It works by increasing the amount of serotonin, a natural substance in the brain that helps maintain mental balance. Escitalopram may cause side effects such as nausea, diarrhea, constipation, changes in sex drive or ability, drowsiness, increased sweating, dizziness, heartburn, stomach pain, excessive tiredness, dry mouth, decreased appetite, weight loss, flu-like symptoms, runny nose, sneezing. Tell your doctor if any of those symptoms are severe or do not go away.