Some common side effects of this medication include: Abnormal dreams, Anxiety or nervousness, Chills, Constipation, Diarrhea, Dizziness, Drowsiness, Dryness of mouth, Heartburn, Increased sweating, Loss of appetite, Nausea, Stuffy or runny nose, Stomach pain or gas, Trembling or shaking, Trouble in sleeping, Unusual tiredness or weakness, Vomiting, Weight loss This medication may raise your blood pressure so, keep a check of=n your blood pressure regularly. 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 such as easy bruising, decreased interest in sex, changes in sexual ability, or muscle cramps then visit your doctor right away.