Zyprexa (olanzapine) is often prescribed for patients suffering from the symptoms of schizophrenia and bipolar disorder. It is not known exactly how this medicine works, but it is thought the effects of Zyprexa are based on affecting certain chemicals in the brain. People with diabetes taking Zyprexa must measure their blood sugar levels regularly to make sure their treatment is both safe and efficient. This medicine can sometimes raise your blood sugar levels, so you will need to contact your health care provider as soon as possible if you get any of the following symptoms: extreme thirst, dry mouth, vomiting, loss of appetite, increased urination, nausea, drowsiness, and dry skin. This drug can cause dizziness, including in cases when you get up after being seated. Make sure you get up slowly to prevent accidental falls. Other side effects you may experience when taking this medication may include back pain, upset stomach, drowsiness, dry mouth, constipation, weakness, increased appetite, and weight gain. Drinking alcohol is not recommended, as it can add to the side effects of Zyprexa you may experience. Such drugs as carbamazepine, high blood pressure medications, Parkinson’s disease medications, and fluvoxamine have been reported to interact with Zyprexa, so do not take any of them without previously consulting your health care provider.