Venlafaxine is a prescription medication primarily used to treat major depressive disorder, anxiety disorders, and panic 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 to help improve mood and emotional balance. Common side effects of venlafaxine may include nausea, dizziness, dry mouth, and increased sweating. It is important for patients to follow their healthcare provider's instructions and discuss any concerns or side effects experienced while taking this medication.