Drug Interactions between olanzapine and Seroquel
This report displays the potential drug interactions for the following 2 drugs:
- olanzapine
- Seroquel (quetiapine)
Interactions between your drugs
OLANZapine QUEtiapine
Applies to: olanzapine and Seroquel (quetiapine)
Consumer information for this interaction is not currently available.
GENERALLY AVOID: There is some concern that quetiapine may have additive cardiovascular effects in combination with other drugs that are known to prolong the QT interval of the electrocardiogram. In clinical trials, quetiapine was not associated with a persistent increase in QT intervals, and there was no statistically significant difference between quetiapine and placebo in the proportions of patients experiencing potentially important changes in ECG parameters including QT, QTc, and PR intervals. However, QT prolongation and torsade de pointes have been reported during post marketing use in cases of quetiapine overdose and in patients with risk factors such as underlying illness or concomitant use of drugs known to cause electrolyte imbalance or increase QT interval. In general, the risk of an individual agent or a combination of agents causing ventricular arrhythmia in association with QT prolongation is largely unpredictable but may be increased by certain underlying risk factors such as congenital long QT syndrome, cardiac disease, and electrolyte disturbances (e.g., hypokalemia, hypomagnesemia). The extent of drug-induced QT prolongation is dependent on the particular drug(s) involved and dosage(s) of the drug(s). In addition, certain agents with anticholinergic properties (e.g., sedating antihistamines; antispasmodics; neuroleptics; phenothiazines; skeletal muscle relaxants; tricyclic antidepressants) may have additive parasympatholytic and central nervous system-depressant effects when used in combination with quetiapine. Excessive parasympatholytic effects may include paralytic ileus, hyperthermia, mydriasis, blurred vision, tachycardia, urinary retention, psychosis, and seizures.
MONITOR: Coadministration of quetiapine with drugs that possess serotonergic activity (e.g., selective serotonin reuptake inhibitors (SSRIs), serotonin-norepinephrine reuptake inhibitors (SNRIs), monoamine oxidase inhibitors (MAOIs), tricyclic antidepressants (TCAs), etc.) may increase the risk of serotonin syndrome, a rare but serious and potentially fatal condition. Combining quetiapine with other serotonergic drugs may increase the risk of serotonin syndrome by relatively enhancing 5-HT1A receptor activity. However, data are currently limited to case reports. In one case report, an 85-year-old woman developed serotonin syndrome within hours of increasing quetiapine from 12.5 mg to 25 mg/day while also taking escitalopram, mirtazapine, sulpiride, and olanzapine; symptoms resolved within 48 hours after the discontinuation of all serotonergic medications. Symptoms of serotonin syndrome may include mental status changes such as irritability, altered consciousness, confusion, hallucination, and coma; autonomic dysfunction such as tachycardia, hyperthermia, diaphoresis, shivering, blood pressure lability, and mydriasis; neuromuscular abnormalities such as hyperreflexia, myoclonus, tremor, rigidity, and ataxia; and gastrointestinal symptoms such as abdominal cramping, nausea, vomiting, and diarrhea.
MANAGEMENT: Coadministration of quetiapine with other drugs that can prolong the QT interval should generally be avoided. Caution and clinical monitoring are recommended if concomitant use of quetiapine with other agents that both prolong the QT interval and possess or enhance serotonergic activity is required. Patients should be advised to seek prompt medical attention if they experience symptoms that could indicate the occurrence of torsade de pointes such as dizziness, lightheadedness, fainting, palpitation, irregular heart rhythm, shortness of breath, or syncope. Patients should also be monitored closely for, and counseled about the signs and symptoms of serotonin syndrome (e.g., altered mental status, hypertension, restlessness, myoclonus, hyperthermia, hyperreflexia, diaphoresis, shivering, and tremor), especially during initiation and dose escalations. Due to variability and occasionally prolonged half-lives of these coadministered agents, consulting individual product labeling for specific guidance is advised.
Drug and food/lifestyle interactions
OLANZapine food/lifestyle
Applies to: olanzapine
Alcohol can increase the nervous system side effects of OLANZapine such as dizziness, drowsiness, and difficulty concentrating. Some people may also experience impairment in thinking and judgment. You should avoid or limit the use of alcohol while being treated with OLANZapine. Do not use more than the recommended dose of OLANZapine, and avoid activities requiring mental alertness such as driving or operating hazardous machinery until you know how the medication affects you. Talk to your doctor or pharmacist if you have any questions or concerns.
Therapeutic duplication warnings
Therapeutic duplication is the use of more than one medicine from the same drug category or therapeutic class to treat the same condition. This can be intentional in cases where drugs with similar actions are used together for demonstrated therapeutic benefit. It can also be unintentional in cases where a patient has been treated by more than one doctor, or had prescriptions filled at more than one pharmacy, and can have potentially adverse consequences.
Antipsychotics
Therapeutic duplication
The recommended maximum number of medicines in the 'antipsychotics' category to be taken concurrently is usually one. Your list includes two medicines belonging to the 'antipsychotics' category:
- olanzapine
- Seroquel (quetiapine)
Note: In certain circumstances, the benefits of taking this combination of drugs may outweigh any risks. Always consult your healthcare provider before making changes to your medications or dosage.
See also
Drug Interaction Classification
Highly clinically significant. Avoid combinations; the risk of the interaction outweighs the benefit. | |
Moderately clinically significant. Usually avoid combinations; use it only under special circumstances. | |
Minimally clinically significant. Minimize risk; assess risk and consider an alternative drug, take steps to circumvent the interaction risk and/or institute a monitoring plan. | |
No interaction information available. |
Further information
Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.
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