Can I take Qutan and Sizodon md together?
Drug interaction guide
Originally published 14 Mar 2026
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Taking these two medicines together can increase the risk of side effects such as extreme sleepiness, dizziness, and confusion. It may also increase the risk of 'orthostatic hypotension' (a sudden drop in blood pressure when you stand up), which can lead to fainting or falls. In some cases, it can increase the risk of heart rhythm problems or movement disorders (shaking or stiffness).
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Why this happens
Both Qutan (quetiapine) and Sizodon MD (risperidone) are antipsychotic medications that work on similar pathways in the brain. Because they both have sedative effects and affect blood pressure regulation, taking them together creates an 'additive effect' where the impact of both drugs is combined.
What you should do
Back to contentsYou must speak to your doctor before taking these two medicines together. They are usually not prescribed at the same time unless specifically managed by a specialist. If your doctor has prescribed both, report any unusual dizziness, fainting, or extreme drowsiness immediately. Be careful when getting out of bed or standing up quickly.
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Important precautions
Back to contentsDementia-related psychosis in elderly patients
These medicines significantly increase the risk of stroke and death in elderly patients with dementia. They are not approved for treating dementia-related behavioural problems.
Neuroleptic Malignant Syndrome (NMS)
Seek emergency medical help immediately if you develop a high fever, severe muscle stiffness, confusion, or rapid heartbeat. This is a rare but life-threatening reaction.
Diabetes and high blood sugar
These medicines can cause extreme increases in blood sugar, even in people without diabetes. Monitor for excessive thirst, frequent urination, or extreme weakness, as this can lead to a life-threatening ketoacidosis.
Food and drink warnings
Back to contentsAlcohol
You must avoid drinking alcohol while taking these medicines. Both Qutan and Sizodon MD can cause significant drowsiness and dizziness. Alcohol will greatly increase these effects, making you feel very sleepy and increasing the risk of falls or accidents.
Grapefruit juice
Avoid drinking grapefruit juice or eating grapefruit while taking Qutan. Grapefruit can increase the amount of this medicine in your blood, which makes side effects much more likely and potentially more severe.
Caffeine (Coffee, tea, cola)
Be cautious with drinks containing caffeine. Caffeine can sometimes interfere with how well Sizodon MD works or may worsen certain side effects like restlessness or tremors.
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Using other medicines
Back to contentsTaking multiple medicines? Our Medicines Interaction Checker helps you check whether your prescriptions, over-the-counter medicines, and supplements are safe to take together. Simply search for your medicines to see potential interactions and what to do about them.
Disclaimer
This information is for general educational purposes only and should not be relied upon as a substitute for professional medical advice. Always consult your GP, pharmacist, or another qualified healthcare professional before making decisions about your medications. Individual circumstances may vary, and only a healthcare professional who knows your medical history can provide personalised guidance.
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Taking fluoxetine with Abilify (aripiprazole) can significantly increase the amount of Abilify in your bloodstream. This makes you much more likely to experience side effects such as extreme sleepiness, restlessness (feeling like you cannot sit still), uncontrollable body movements (tremors or twitching), and dizziness. There is also a small but serious risk of a heart rhythm problem called QT prolongation.

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Can I take Vitamin c and Vitamin d3 together?
There is no known harmful interaction between Vitamin C (ascorbic acid) and Vitamin D3 (cholecalciferol). In fact, these two vitamins are often taken together to support overall health.
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Article history
The information on this page is written and peer reviewed by qualified clinicians.
14 Mar 2026 | Originally published

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