What it is used for
- Schizophrenia
- Bipolar disorder (mania, depression and maintenance)
- Add-on treatment for depression (in some regions)
How it works
Quetiapine acts on several brain chemical messengers, particularly dopamine and serotonin, helping to rebalance signalling that affects mood, thinking and perception.
How it is taken
Usually available as standard and modified-release (extended-release) tablets taken by mouth. The amount is usually built up gradually. Take it exactly as your doctor or pharmacist directs and follow the label; the modified-release form is swallowed whole, and you should not stop suddenly.
No doses here on purpose. The right strength and schedule depend on you — only a doctor or pharmacist should set them. Always follow your prescription and the label.
Common side effects
- Drowsiness
- Dizziness, especially on standing
- Dry mouth
- Weight gain
- Constipation
- Increased appetite
- Headache
- Tiredness
Serious effects — get help
- Signs of high blood sugar or diabetes: excessive thirst, frequent urination, weakness
- Marked weight gain and changes in blood fats over time
- Irregular or fast heartbeat, fainting
- Uncontrolled movements of the face or body (may persist)
- Neuroleptic malignant syndrome: high fever, severe muscle stiffness, confusion (medical emergency)
- Signs of low white blood cells: fever, sore throat, infections
- New or worsening suicidal thoughts
If a reaction is severe — for example trouble breathing, swelling of the face or throat, or collapse — go to the nearest emergency room now or call your local emergency number. Do not wait for an online consultation.
Interactions to watch
- Alcohol and other sedating medicines (added drowsiness)
- Medicines that affect heart rhythm
- Some medicines that strongly change how the liver processes it (certain antifungals, antibiotics, seizure medicines)
- Blood-pressure medicines (added drop in blood pressure)
Who should take care
- Can affect blood sugar, blood fats and weight, so these may be monitored
- May cause dizziness on standing, especially when starting; rise slowly
- Use with caution with heart conditions, diabetes, seizures or in older adults with dementia (higher risks)
- Tell your clinician if you are pregnant, planning pregnancy or breastfeeding
- Do not stop suddenly; taper under medical guidance