Get emergency medical help if you have signs of an allergic reaction to Silenor: hives; difficulty breathing; swelling of your face, lips, tongue, or throat. Some people using this medicine have engaged in activity while not fully awake and later had no memory of it. This may include walking, driving, or making phone calls. If this happens to you, call your doctor right away. Call your doctor at once if you have: unusual thoughts or behavior; confusion, hallucinations; depressed mood, thoughts about hurting yourself; uncontrolled muscle movements; a seizure; a light-headed feeling, like you might pass out; blisters or ulcers in your mouth, red or swollen gums, trouble swallowing; eye pain or redness; chest pain; low red blood cells (anemia) - pale skin, unusual tiredness, feeling light-headed or short of breath, cold hands and feet; or signs of infection - flu-like symptoms, swelling, skin redness, diarrhea, skin sores or white patches, trouble breathing, pain or burning when you urinate.