Duloxetine HCl, equivalent to duloxetine 10mg, 20mg, 30mg, 40mg, and 60mg, is a serotonin-norepinephrine reuptake inhibitor (SNRI) commonly used in the treatment of depression, generalized anxiety disorder, chronic pain, and fibromyalgia. By increasing the levels of serotonin and norepinephrine in the brain, it helps improve mood, reduce anxiety, and alleviate pain. Duloxetine is typically taken once daily, and its dosage may vary depending on the condition being treated. Side effects can include nausea, dry mouth, drowsiness, fatigue, and dizziness, but these usually improve over time. Rare, but serious side effects may include an increased risk of suicidal thoughts, particularly in younger patients, as well as liver damage and hypertension. Patients should be closely monitored, especially when starting the medication or adjusting doses. Duloxetine should not be stopped abruptly, as this can lead to withdrawal symptoms.