Zyprexa (Olanzapine) Side Effects

Common and Rare Side Effects of Zyprexa

Mental health professional prescribing medication

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Zyprexa (olanzapine) is an atypical antipsychotic medication used in the treatment of bipolar disorder, schizophrenia, and treatment-resistant depression. It can be used for new onset of disease and long term maintenance of schizophrenia. For bipolar disorder, it is considered a first line therapy for acute mania—and it is often combined with Prozac (fluoxetine). Zyprexa side effects are possible (as with most medicines), but its benefits may outweigh the side effects for you.

Commonly Reported Zyprexa Side Effects

Common side effects of Zyprexa include:

  • Sleepiness or excessive sleeping
  • Dizziness
  • Weight gain
  • Dry mouth
  • Lack of energy
  • Increased appetite
  • Tremor
  • Hard or infrequent stools
  • Change in behavior
  • Restlessness

Be sure to consult your doctor if any of these side effects bother you or persist. Also, there are some more unique side effects that teenagers may experience with Zyprexa, so be sure to review these with your doctor. Adolescents are more likely to experience weight gain, hyperlipidemia (a condition where there are high levels of lipids in the blood), increased sedation, and increased prolactin and liver enzyme levels.

Potential Serious Side Effects With Zyprexa

One important and serious side effect of Zyprexa is significant weight gain, which is often a huge reason a patient will stop medication. In addition, Zyprexa can also increase blood sugar levels, putting a person at risk for developing diabetes. Zyprexa may also increase an individual's cholesterol levels. All of these factors can increase the patient's risk of heart disease. This is why it's important to review an exercise and nutritional plan with your doctor while on Zyprexa to help minimize side effects such as the ones below.

  • Neuroleptic malignant syndrome (NMS): Signs include muscle rigidity, confusion, high fever, increased blood pressure and heart rate, and abnormal heart rhythms.
  • Tardive dyskinesia: Condition causes repetitive, involuntary movements such as blinking, though the risk of tardive dyskinesia on Zyprexa is lower when compared to typical or first-generation antipsychotics.
  • Heat sensitivity: You also may be more sensitive to heat due to reduced sweating. So be sure to drink plenty of water, especially in hot weather or before and after exercising.
  • Seizures: Zyprexa can lower the seizure threshold, though this is a rare occurrence.
  • Dysphagia: Problems swallowing may exist
  • Stroke: An increased risk of strokes in elderly people with dementia-related psychosis exists.
  • Orthostatic hypotension: This is dizziness or fainting when going from sitting to standing due to low blood pressure.
  • Weight gain: This is incredibly common on Zyprexa; nearly 65% of those on it will gain weight. It's important to note that weight gain is also dose dependent—the higher your dosage is, the more weight you are likely to gain.

    What If My Doctor Prescribes Zyprexa?

    You'll want to share with your doctor of all the medications you take including prescription medication, herbals, vitamins, and any over-the-counter medications. Some medications interact with Zyprexa and may cause serious side effects or require that your doctor change your dose.

    You may also want to ask your doctor if any similar medicines, such as Abilify (aripiprazole) might be more effective—Abilify has a lower side effect profile than Zyprexa.

    Never start or stop Zyprexa without seeking the advice of your doctor.

    It's also important to give your doctor a complete medical history, including all your medical problems and any allergies. For example, tell your doctor if you are lactose-intolerant, as Zyprexa tablets contain lactose. Also, tell your doctor if you drink alcohol, as alcohol should not be used when taking Zyprexa. If you are breastfeeding, you may want to consider a different medication, as this medication is excreted in breast milk.

    Finally, when on Zyprexa, take it at the same time every day. If you accidentally forget a dose, take it as soon as you remember—unless it's almost time for the next dose anyway. Then skip it, and take your regular dose as scheduled. Do not take two doses of Zyprexa at the same time. If you are unsure about your timing, call your doctor to be safe.

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