Common symptoms include:
• Persistent sad, anxious, or "empty" mood and unexplained crying spells
• Feelings of hopelessness, pessimism, guilt feeling, worthlessness
• Loss of interest or pleasure in hobbies and activities that were once enjoyed, including sex, social withdrawal
• Loss of energy, persistent lethargy
• Difficulty concentrating, remembering, making decisions
• Insomnia, early-morning awakening, or oversleeping
• Appetite and/or weight loss or overeating and weight gain
• Thoughts of death or suicide; suicide attempts
• Restlessness, irritability, anger, agitation
• Persistent physical symptoms that do not respond to treatment, such as headaches, digestive disorders, and chronic pain