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) for bipolar depression. 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

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

Potential Serious Side Effects With Zyprexa

One common and possibly serious side effect of Zyprexa is significant weight gain, which is has been reported as one of the top reasons people choose to stop taking the medication. Nearly 65% of those who take Zyprexa will gain weight, but it's important to note that weight gain is also dose-dependent—the higher your dosage, the more weight you are likely to gain.

In addition, Zyprexa can increase blood sugar levels, putting a person at risk for developing diabetes. Zyprexa may also increase an individual's cholesterol levels.

All three of these factors combined—weight gain, high blood sugar, and high cholesterol—can increase the patient's risk of heart disease, which is why it's important to review an exercise and nutritional plan with your doctor while on Zyprexa.

Other serious side effects of Zyprexa can include:

  • Neuroleptic malignant syndrome (NMS): Signs include muscle rigidity, confusion, high fever, alterations in blood pressure and heart rate, and abnormal heart rhythms.
  • Tardive dyskinesia: Condition that can occur with the long term use of antipsychotics that causes repetitive, involuntary movements, 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. 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 occur
  • Stroke: An increased risk of strokes in elderly people with dementia-related psychosis also exists.
  • Orthostatic hypotension: This is dizziness or fainting when going from sitting to standing due to low blood pressure.

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.

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 be used cautiously if at all when taking Zyprexa. If you are breastfeeding, you should discuss the potential risks of this with your doctor.

Finally, when on Zyprexa, try and 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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