Symbyax was developed by Eli Lilly as a drug to treat bipolar disorder and depression. It is a combination of the company’s blockbuster antidepressant Prozac and an antipsychotic called Zyprexa. It is designed to treat tough cases of depression. The depressive phases of bipolar are difficult to treat and some people with major depression don’t respond to many medications. In these cases, Symbyax may be useful.
Unfortunately there are plenty of potential Symbyax side effects, and they range from mild and not worrying to serious and possibly life-threatening. Birth defects in the children of mothers who took the drug during pregnancy, suicide in young patients, death in elderly patients, and many other devastating consequences are potential side effects of Symbyax.
What is Symbyax?
Symbyax is a combination of Prozac and Zyprexa. It was approved by the U.S. Food and Drug Administration (FDA) in 2003 for the treatment of depressive phases of bipolar disorder. The FDA expanded that to include certain cases of major depression in 2009. It is indicated for people struggling with depression who have not responded to other treatments.
Prozac is an antidepressant called fluoxetine, which has been in use since 1987. It acts to increase a chemical in the brain called serotonin. Zyprexa is a second generation antipsychotic, olanzapine, which also acts on brain chemicals. It acts on both serotonin and dopamine. Zyprexa has been available since the 1990s for treating mania in bipolar disorder and schizophrenia.
Common Side Effects
Symbyax side effects range from mild to severe, but most commonly they are not too serious. Those most reported are not problematic for most patients unless they get worse or persist. For many these side effects resolve themselves over time.
Common side effects of Symbyax include an increased appetite followed by weight gain, sleepiness, fatigue, edema, dry mouth, blurry vision, tremors and shaking, and difficulty paying attention for an extended period of time. Children and teens are susceptible to the same side effects but may also experience elevated triglyceride and cholesterol levels, possibly related to weight gain.
In addition to the common and less severe side effects of Symbyax, there are also several very serious possible complications. Some are caused by Prozac and others by Zyprexa or both. The risk of suicide is caused by Prozac. In the early 2000s it was discovered that many antidepressants could increase the risk that a teen or child would experience suicidal thoughts and even act on them.
The FDA officially warned about this risk and required that medications, including Symbyax, include a black box on the label. This warning states that the drug could cause suicidal thoughts and behaviors in children, teens, and adults under the age of 25. No one knows for sure why this happens and why it only seems to be an issue in younger people.
The FDA has allowed Symbyax to be used in children ten years old and older, but only for the treatment of bipolar depression. It is difficult to treat and not many medications help, so the FDA expects doctors to carefully weigh the risks and benefits and to discuss the suicidal side effects with patients and their parents before using it for bipolar children. Children and teens using the drug should also be carefully monitored for signs of suicidal thoughts.
Death in Elderly Patients
Symbyax also carries a black box warning for a potential side effect caused by Zyprexa. Studies have found that some second generation antipsychotics increase the risk of death in elderly patients who exhibit signs of dementia. The risk of dying while on the drug is close to two times the risk of dying for other elderly patients with dementia not taking these kinds of antipsychotic drugs. Symbyax is not indicated for this special population as a result.
Another very serious side effect of Symbyax occurs with yet another specific population: the children of mothers who used Symbyax while pregnant. There is evidence that Prozac can cause birth defects and complications when used during pregnancy. Craniosynostosis, a skull defect and a defect of the right ventricle of the heart are especially connected to Prozac, but other defects like cleft palate and spina bifida are possible.
Most of the information about how antidepressants like Prozac cause birth defects have come from individual reports. Evidence from studies is now accumulating, though, and backing up these case studies. In addition to birth defects, there is now evidence that a child born to a mother who used Prozac is at risk for persistent pulmonary hypertension of the newborn, a dangerous breathing problem that can be fatal in a newborn.
Serotonin is an important brain chemical that is implicated in mood, but exactly how it works is not fully understood. Too little serotonin is linked with depression, but too much can cause a dangerous condition called serotonin syndrome. Because both drugs in Symbyax act on serotonin, users are at risk for developing this condition as a serious side effect.
If any signs of serotonin syndrome are seen in someone taking Symbyax, that person needs to seek treatment immediately. The signs include getting overheated, feeling nauseated, vomiting, diarrhea, having hallucinations, feeling anxious and agitated, and an irregular heartbeat. It can end in a coma if not treated.
Other Serious Side Effects
In addition to serotonin syndrome, suicide, and birth defects, there are some other serious Symbyax side effects which are less common.. Zyprexa can cause a serious condition called neuroleptic malignant syndrome, or NMS. It is characterized by an irregular pulse, changing blood pressure, muscle rigidity, and unusual changes in mood. NMS can be fatal if not treated.
Symbyax users are also at risk for hyperglycemia, or high blood sugar. If this happens and is not brought under control, it can eventually lead to type 2 diabetes, which in turn causes a number of health complications. For some patients, this is severe enough to require discontinuation of Symbyax and ongoing treatment for type 2 diabetes.
The side effects of Symbyax have proven to be severe enough that some people have filed lawsuits against Eli Lilly. Plaintiffs claim that the company did not do enough to warn them of the risks of using the medication, especially the risks of birth defects and complications.