Desvenlafaxine is a prescription medication primarily used to treat major depressive disorder. It belongs to a class of drugs known as serotonin-norepinephrine reuptake inhibitors (SNRIs), which work by increasing the levels of certain neurotransmitters in the brain, helping to improve mood and alleviate symptoms of depression. This medication is usually taken orally in the form of a tablet and is often prescribed when other antidepressants have not been effective. Common side effects may include nausea, dizziness, and dry mouth. It is important for patients to follow their healthcare provider's instructions and report any unusual symptoms.