Olanzapine
Warning
There may be a slightly increased risk of serious, possibly fatal side effects (such as stroke, heart failure, fast/irregular heartbeat, pneumonia) when this medication is used by older adults with dementia. This medication is not approved for the treatment of dementia-related behavior problems. Discuss the risks and benefits of this medication, as well as other effective and possibly safer treatments for dementia-related behavior problems, with the doctor.
If you are using olanzapine in combination with other medication to treat depression, also carefully read the drug information for the other medication.
Precautions
Before taking olanzapine, tell your doctor or pharmacist if you are allergic to it; or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.
Before using this medication, tell your doctor or pharmacist your medical history, especially of: liver problems, seizures, difficulty swallowing, low white blood cell count, dementia, difficulty urinating (for example, due to enlarged prostate), glaucoma (narrow angle), stomach/intestinal problems (such as blockage, chronic constipation, paralytic ileus), smoking, personal or family history of diabetes, heart disease, high cholesterol/triglyceride levels, breathing trouble during sleep (sleep apnea).
This drug may make you dizzy or drowsy. Alcohol or marijuana (cannabis) can make you more dizzy or drowsy. Do not drive, use machinery, or do anything that needs alertness until you can do it safely. Avoid alcoholic beverages. Talk to your doctor if you are using marijuana (cannabis).
Before having surgery, tell your doctor or dentist about all the products you use (including prescription drugs, nonprescription drugs, and herbal products).
This medication may make you sweat less, making you more likely to get heat stroke. Avoid doing things that may cause you to overheat, such as hard work or exercise in hot weather, or using hot tubs. When the weather is hot, drink a lot of fluids and dress lightly. If you overheat, quickly look for a place to cool down and rest. Get medical help right away if you have a fever that does not go away, mental/mood changes, headache, or dizziness.
Teenagers may be more sensitive to the side effects of this drug, especially weight gain, and also increased amounts of cholesterol, triglycerides, and prolactin. See also Side Effects section for more details.
Older adults may be more sensitive to the side effects of this drug, especially drowsiness, constipation, trouble urinating, confusion, dizziness, and lightheadedness. Drowsiness, confusion, dizziness, and lightheadedness can increase the risk of falling.
During pregnancy, this medication should be used only when clearly needed. Babies born to mothers who have used this drug during the last 3 months of pregnancy may rarely develop symptoms including muscle stiffness or shakiness, drowsiness, feeding/breathing difficulties, or constant crying. If you notice any of these symptoms in your newborn especially during their first month, tell the doctor right away.
Since untreated mental/mood problems (such as schizophrenia, bipolar disorder, depression) can be a serious condition, do not stop taking this medication unless directed by your doctor. If you are planning pregnancy, become pregnant, or think you may be pregnant, immediately discuss with your doctor the benefits and risks of using this medication during pregnancy.
This drug passes into breast milk and may have undesirable effects on a nursing infant. Tell the doctor right away if your baby develops symptoms such as muscle stiffness or shakiness, unusual sleepiness, or difficulty feeding. Consult your doctor before breastfeeding.
Side Effects
Drowsiness, dizziness, lightheadedness, stomach upset, dry mouth, constipation, increased appetite, or weight gain may occur. If any of these effects last or get worse, tell your doctor or pharmacist promptly.
Dizziness and lightheadedness can increase the risk of falling. Get up slowly when rising from a sitting or lying position.
Remember that this medication has been prescribed because your doctor 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 right away if you have any serious side effects, including: difficulty swallowing, shaking (tremor), slow heartbeat, fainting, mental/mood changes (such as confusion, restlessness), numbness/tingling of arms/legs, yellowing eyes/skin, severe stomach/abdominal pain, trouble urinating, interrupted breathing during sleep.
This drug may rarely make your blood sugar rise, which can cause or worsen diabetes. Tell your doctor right away if you have symptoms of high blood sugar such as increased thirst/urination. If you already have diabetes, check your blood sugar regularly as directed and share the results with your doctor. Your doctor may need to adjust your diabetes medication, exercise program, or diet.
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.)
Olanzapine may rarely cause a condition known as tardive dyskinesia. In some cases, this condition may be permanent. Tell your doctor right away if you develop any unusual/uncontrolled movements (especially of the face, lips, mouth, tongue, arms or legs).
This medication may increase a certain natural substance (prolactin) made by your body. For females, this increase in prolactin may result in unwanted breast milk, missed/stopped 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 right away.
Get medical help right away if you have any very serious side effects, including: seizures.
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, signs of kidney problems (such as change in the amount of urine).
A very serious allergic reaction to this drug is rare. However, get medical help right away if you notice any symptoms of a serious allergic reaction, including: fever, swollen lymph nodes, 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 or at www.fda.gov/medwatch.
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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