Some common side effects of this medication include: Abnormal dreams, Anxiety or nervousness, Blurred vision, Chills, Constipation, Diarrhea, Difficulty sleeping, Dizziness/drowsiness, Dryness of mouth, Heartburn, Increased sweating, Loss of appetite, Vomiting and nausea, Stuffy or runny nose, Stomach pain or gas, Nervousness (trembling or shaking), Unusual tiredness or weakness, Weight loss Keep in mind that your doctor has prescribed you this medication because its benefits to you are greater than the risk of side effects. Many people who use this medication do not have serious side effects. However, if you undergo any serious side effects as mentioned below, notify your doctor right away. Easy bruising/bleeding, Decreased interest in sex, Changes in sexual ability, Muscle cramps/weakness, Shaking (tremor), Black/bloody stools, Persistent cough, Seizure, Severe headache, Shortness of breath, Vomit that looks like coffee grounds, Hallucinations, Unusual restlessness, Loss of coordination, Irregular heartbeat, severe dizziness, Unexplained fever, Twitching muscles