WARNING: THIS MEDICINE CONTAINS ACETAMINOPHEN. Severe and sometimes fatal liver problems, including the need for liver transplant, have been reported with the use of acetaminophen. Most cases of these liver problems occurred in patients taking excessive doses of acetaminophen (more than 4,000 mg per day). Also, patients who developed these liver problems were often using more than 1 medicine that contained acetaminophen. Discuss any questions or concerns with your doctor. Some medicines or medical conditions may interact with this medicine. INFORM YOUR DOCTOR OR PHARMACIST of all prescription and over-the-counter medicine that you are taking. DO NOT TAKE THIS MEDICINE if you are also taking sodium oxybate (GHB). ADDITIONAL MONITORING OF YOUR DOSE OR CONDITION may be needed if you are taking anticoagulants (eg, warfarin), buprenorphine, isoniazid, linezolid, monoamine oxidase inhibitors (MAOIs) (eg, phenelzine), naltrexone, other narcotic pain medicines (eg, morphine), perampanel, sleep medicines (eg, zolpidem), tricyclic antidepressants (eg, amitriptyline), or medicines that may harm the liver (eg, methotrexate, ketoconazole, certain medicines for HIV infection). Ask your doctor if you are unsure if any of your medicines might harm the liver. DO NOT START OR STOP any medicine without doctor or pharmacist approval. Inform your doctor of any other medical conditions, including a history of liver problems (eg, hepatitis), kidney problems, lung or breathing problems (eg, asthma, chronic obstructive pulmonary disease / COPD), drug or alcohol abuse or dependence, heart problems (eg, cor pulmonale, slow or irregular heartbeat), low blood pressure, stomach or bowel problems (eg, blockage, inflammation, paralysis), gallbladder problems, prostate problems (eg, an enlarged prostate), difficulty urinating, seizures, thyroid problems, adrenal gland problems (eg, Addison disease), mental or mood problems, inflammation of the pancreas (pancreatitis), curvature of the spine (scoliosis), suicidal thoughts or actions, allergies, pregnancy, or breast-feeding. Tell your doctor if you have severe drowsiness, or have or recently have had any head injury, increased pressure in the brain, growths in the brain (eg, tumors), or infection of the brain or nervous system. Tell your doctor if you have recently had surgery (eg, stomach or bowel surgery) or are scheduled to have surgery. Tell your doctor if you are in very poor health; are very overweight or are dehydrated; have low blood volume, stomach pain, or constipation; drink alcohol; or are going through withdrawal from alcohol or other substances. USE OF THIS MEDICINE IS NOT RECOMMENDED if you have very slow or difficult breathing, or you are having an asthma attack. Contact your doctor or pharmacist if you have any questions or concerns about taking this medicine.