Quetiapine
An antipsychotic for schizophrenia and bipolar disorder. Effective where it’s meant to be used. Low doses for sleep or anxiety bring the risks without much benefit.
Quick answer: Quetiapine is an antipsychotic for schizophrenia and bipolar disorder. Common side effects include drowsiness, dizziness, dry mouth, weight gain, and raised blood sugar and cholesterol, which are checked regularly. Low doses for sleep or anxiety are off-label and not recommended, because the risks outweigh the benefits. Don’t stop it suddenly; reduce it slowly with your doctor.
At a glance
- For
- Schizophrenia, bipolar disorder (mania, depression, prevention); added to an antidepressant (extended-release)
- Works
- Effective for psychosis and bipolar mood episodes. In bipolar depression, about 6 in 10 respond, versus about a third on a dummy treatment
- Cost
- $25 or less on the PBS for schizophrenia and bipolar disorder ($7.70 concession); off-label use is private
- Kicks in
- Drowsiness within hours; mood and psychosis improve over 1–6 weeks
- Taken for
- Often long term, with regular reviews
- Watch for
- Drowsiness, weight gain, dizziness on standing, dry mouth, raised blood sugar and cholesterol
A “tiny dose for sleep” still brings the weight and blood sugar baggage. Better sleep fixes exist, starting with CBT for insomnia.
Brand names
- Seroquel, Seroquel XR (extended-release), plus generic brands
How it works
It blocks dopamine and serotonin receptors, steadying psychosis and mood. Its antihistamine effect causes drowsiness.
Used for
- Schizophrenia (TGA-approved)
- Bipolar disorder: mania, depression and preventing relapse (TGA-approved)
- Major depression, added to an antidepressant (Seroquel XR, TGA-approved)
- Low doses for sleep or anxiety are off-label and not recommended. The risks (weight gain, diabetes, high cholesterol, heart rhythm changes) outweigh the benefits
Side effects
Full side-effect list (from the product information)
How often, from the official product information. Bold = serious.
Very common more than 1 in 10
- Drowsiness, dizziness, headache
- Dry mouth, lower haemoglobin
- Weight gain
- Raised cholesterol, triglycerides
- Stiffness, tremor, restlessness
- Withdrawal if stopped suddenly
Common 1 in 10 to 1 in 100
- Low white cells, thyroid changes
- High blood sugar, more appetite
- Raised prolactin, liver enzymes
- Odd dreams, suicidal thoughts
- Fast heartbeat, breathlessness
- Dizzy on standing, blurred vision
- Constipation, indigestion, vomiting
- Weakness, swollen ankles, fever
Uncommon 1 in 100 to 1 in 1,000
- Low neutrophils or platelets
- Diabetes, low sodium
- Allergy, underactive thyroid
- Seizures, fainting, confusion
- Tardive dyskinesia (lasting tics)
- Long QT, slow heart rate
- Swallowing, urine or sexual problems
Rare 1 in 1,000 to 1 in 10,000
- Agranulocytosis (no white cells)
- Neuroleptic malignant syndrome
- Pancreatitis, bowel blockage
- Jaundice, hepatitis, blood clots
- Metabolic syndrome, sleepwalking
- Prolonged erection, period changes
Very rare fewer than 1 in 10,000
- Anaphylaxis or angioedema
- Stevens-Johnson syndrome
- Muscle breakdown
Frequency not known reported, rate unclear
- Heart muscle inflammation
- Severe skin reactions
- Stroke
- Withdrawal in newborns
Get help urgently if
- High fever, stiff muscles, confusion and sweating (possible neuroleptic malignant syndrome)
- Fever, sore throat or mouth ulcers (possible low white cells)
- Chest pain, fainting or a racing, irregular heartbeat
- Very thirsty and passing lots of urine (high blood sugar)
- Thoughts of suicide or self-harm: Lifeline 13 11 14, or 000
Good to know
- Metabolic monitoring: weight, waist, blood pressure, blood sugar and cholesterol are checked before starting and regularly after.
- Not approved for dementia: higher risk of stroke and death in older people with dementia.
- Avoid alcohol. Don’t drive until you know how it affects you. Grapefruit juice and some antibiotics and antifungals raise levels.
- Stopping: reduce slowly to avoid nausea, vomiting, poor sleep and relapse. Pregnancy or breastfeeding: discuss with your doctor before starting or stopping.
Support lines
If you or someone else is in danger right now, call your emergency number. To talk to someone, any time:
- Australia: Lifeline 13 11 14 (24/7, or text 0477 13 11 14), Suicide Call Back Service 1300 659 467, Beyond Blue 1300 22 4636, 13YARN 13 92 76 for Aboriginal and Torres Strait Islander people. Emergency: 000.
- Young people in Australia: Kids Helpline 1800 55 1800 (24/7, ages 5 to 25) or headspace (ages 12 to 25).
- New Zealand: call or text 1737. Emergency: 111.
- UK and Ireland: Samaritans 116 123. Emergency: 999 (or 112).
- US and Canada: call or text 988. Emergency: 911.
- Anywhere else: findahelpline.com lists free helplines in more than 100 countries.
Common questions
Is quetiapine used for sleep?
Low doses for sleep or anxiety are off-label and not recommended. The risks, such as weight gain, diabetes, high cholesterol and heart rhythm changes, outweigh the benefits.
Does quetiapine cause weight gain?
Yes, weight gain is very common. Weight, waist, blood pressure, blood sugar and cholesterol are checked before starting and regularly after.
Can I stop quetiapine suddenly?
No. Reduce it slowly with your doctor to avoid nausea, vomiting, poor sleep and relapse.
What is quetiapine used for?
It is TGA-approved for schizophrenia and bipolar disorder (mania, depression and preventing relapse), and the extended-release form (Seroquel XR) for major depression when added to an antidepressant. Low doses for sleep or anxiety are off-label and not recommended.
What are the common side effects of quetiapine?
Drowsiness, dizziness, headache, dry mouth, weight gain and raised cholesterol are very common. Dizziness on standing, constipation, more appetite and raised blood sugar are common, which is why weight, blood sugar and cholesterol are checked regularly.
How long does quetiapine take to work?
Drowsiness comes on within hours. Improvements in mood or psychosis build over 1 to 6 weeks.
Information only. Not a recommendation or endorsement of any product. Whether a medicine suits you depends on your health and other medicines, so talk to your doctor or pharmacist. In an emergency, call 000 (Australia) or your local emergency number. From a mobile, 112 works in most countries.
More information
- Seroquel 100 mg SmPC (UK)
- Healthdirect: Medicines information
- Lifeline: 13 11 14
- Calabrese et al. 2005: Quetiapine for bipolar depression (BOLDER)
maladywise.com/medicines/quetiapine/