Key takeaways
Olanzapine (Zyprexa) and lithium (Lithobid) are both prescription medications used to treat bipolar disorder, but they have some important differences. Olanzapine is an atypical antipsychotic, while lithium is a mood stabilizer. Olanzapine is also used for schizophrenia and, in combination with fluoxetine, for treatment-resistant depression, whereas lithium is specifically used for manic episodes and long-term maintenance of bipolar disorder. Olanzapine is typically taken once daily and is available in oral and injectable forms. Olanzapine side effects include weight gain and sleepiness. Lithium, on the other hand, is taken 2 to 3 times a day, is available as oral tablets, capsules, and liquid, and requires regular blood tests. Common side effects of lithium include shakiness, thirst, and nausea. Olanzapine can cause anticholinergic side effects and affect blood sugar levels, while lithium can interact with many medications and affect kidney and thyroid function. Do not take OTC non-steroidal anti-inflammatory drugs (NSAIDs), like ibuprofen (Motrin) or naproxen (Aleve), with lithium without talking to your prescriber first.
