SIDE EFFECTS: See also the Warning section.Dizziness, drowsiness, diarrhea, dry mouth, constipation, increased appetite, weight gain, or trouble sleeping may occur. If any of these effects persist or worsen, tell your doctor or pharmacist promptly.Remember that your doctor has prescribed this medication because he or she has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.Tell your doctor immediately if any of these unlikely but serious side effects occur: unusual or severe mental/mood changes (e.g., confusion, nervousness, trouble concentrating, rare thoughts of suicide), swelling hands/ankles/feet, restlessness, shaking (tremor), inability to keep still, decreased interest in sex, changes in sexual ability, large pupils, trouble urinating.Tell your doctor immediately if any of these rare but very serious side effects occur: black stools, vomit that looks like coffee grounds, easy bruising/bleeding, muscle spasm, yellowing eyes/skin, severe stomach/abdominal pain, slow heartbeat, signs of infection (such as fever, persistent sore throat).Get medical help right away if any of these rare but serious side effects occur: fainting, severe headache, seizures.This drug may infrequently make your blood sugar level rise, an effect that may cause or worsen diabetes. This high blood sugar can rarely cause serious conditions such as diabetic coma. Tell your doctor immediately if you develop symptoms of high blood sugar, such as increased thirst/urination or unexplained weakness. If you already have diabetes, be sure to check your blood sugars regularly and share the results with your doctor. Your doctor may need to adjust your medication, diet, and exercise program when you start or stop this medication.This drug may also cause significant weight gain and a rise in your blood cholesterol (or triglyceride) levels, especially in teenagers. These effects, along with diabetes, may increase your risk for developing heart disease. Discuss the risks and benefits of treatment with your doctor. (See also Notes section.)This medication may increase serotonin and rarely cause a very serious condition called serotonin syndrome/toxicity. The risk increases if you are also taking other drugs that increase serotonin, so tell your doctor or pharmacist of all the drugs you take (see Drug Interactions section). Get medical help right away if you develop some of the following symptoms: fast heartbeat, hallucinations, loss of coordination, severe dizziness, severe nausea/vomiting/diarrhea, twitching muscles, unexplained fever, unusual agitation/restlessness.This medication may rarely cause a very serious condition called neuroleptic malignant syndrome (NMS). Get medical help right away if you have any of the following symptoms: fever, muscle stiffness/pain/tenderness/weakness, severe tiredness, severe confusion, sweating, fast/irregular heartbeat, dark urine, change in the amount of urine.Olanzapine may rarely cause a condition known as tardive dyskinesia. In some cases, this condition may be permanent. Tell your doctor immediately if you develop any unusual/uncontrolled movements (especially of the face/lips/tongue).In rare cases, this medication may increase your blood level of a certain hormone (prolactin). For females, this rare increase in prolactin levels may result in unwanted breast milk, irregular/stopped menstrual periods, or difficulty becoming pregnant. For males, it may result in decreased sexual ability, inability to produce sperm, or enlarged breasts. If you develop any of these symptoms, tell your doctor immediately.For males, in the very unlikely event you have a painful or prolonged erection lasting 4 or more hours, stop using this drug and seek immediate medical attention, or permanent problems could occur.A very serious allergic reaction to this drug is rare. However, seek immediate medical attention if you notice any symptoms of a serious allergic reaction, including: rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, trouble breathing.This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.In the US -Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.
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