Fluoxetine is a medication commonly used to treat depression, anxiety disorders, and certain other mental health conditions. It belongs to a class of drugs known as selective serotonin reuptake inhibitors (SSRIs), which work by increasing the levels of serotonin, a neurotransmitter that helps regulate mood. Typically prescribed in pill form, fluoxetine can take several weeks to show its full effects. Common side effects may include nausea, insomnia, and changes in appetite. It is important for patients to follow their healthcare provider's instructions and discuss any concerns or side effects experienced during treatment.