Quetiapine | Atypical Antipsychotic Use & Side Effects

Medication name

Quetiapine ("qwe-TIE-a-peen")
Brand name

Seroquel® ("SERR-oh-kwell")
Medication type

Second-generation antipsychotic (sometimes referred to as an ‘atypical antipsychotic)

Tablets: 25mg, 100mg, 150mg, 200mg, and 300mg strengths

Prolonged-release tablets: 50mg, 150mg, 200mg, 300mg, and 400mg strengths

Liquid: 20mg in 1ml (100mg in each 5ml spoonful)

Quetiapine can be prescribed for schizophrenia.

It can also be prescribed to treat manic or depressive episodes if you have bipolar disorder, and to prevent further episodes from happening.

It is sometimes added to antidepressants in the treatment of major depression.

If you are 18 or over, the doctor can prescribe quetiapine for you as a licensed medicine for schizophrenia.

If you are younger than 18, a specialist doctor may still consider this as a treatment option.

A specialist may also discuss this as an option for other conditions including anxiety and post-traumatic stress disorder.

Read our guide to schizophrenia

About quetiapine

Quetiapine is a second-generation antipsychotic (sometimes described as an ‘atypical antipsychotic’). It may also be described as a mood stabiliser.

Dopamine is a chemical messenger (or ‘neurotransmitter’) in the brain mainly involved with thinking, emotions, behaviour and perception. In some illnesses, there may be too much dopamine, causing some unwanted symptoms. The main effect that quetiapine has is to block the effects of dopamine in the brain, resulting in a reduction of symptoms.

Quetiapine also has effects on other neurotransmitters in the brain such as serotonin. Its beneficial effects may be related to this as well, including the reduction of movement disorders and symptoms of depression and anxiety.

Quetiapine and everyday life

You should experience some benefits within the first one to two weeks of taking it, but it can take four to six weeks, sometimes longer, for quetiapine to show its full effects. This can vary between individuals and the reason why you are taking it.

You should stay in touch with your doctor to see how it goes over the first few weeks. They might do some tests to check your symptoms.

If you have had no good effects at all after two weeks, you should talk to your doctor about your progress. They may recommend increasing the dose or changing your medicine. Don’t increase your dose yourself if you think the medication isn’t working.

Your doctor will start with a low dose, which they will increase slowly until you find a dose that is effective for you. This may take several days or weeks.

Quetiapine can cause weight loss or weight gain. Weight gain is more common than weight loss.

The risk of weight gain with quetiapine is lower compared to other antipsychotic medicine (like olanzapine), but children and young people appear to be more at risk of this side effect compared with adults. You may also be more likely to gain weight if you have not taken this type of medication before.

It is very difficult to know how it will affect each person who takes it. Talk to your doctor or pharmacist if you are concerned about your weight, or changes to your weight, while taking quetiapine. They can review your medicine with you and look at any changes that could be made to help.

Making sure you do enough exercise and eat a healthy diet (with vegetables and fibre) can help you to avoid putting on too much weight.

Mental health conditions like schizophrenia and bipolar disorder can make being active and eating healthily more of a challenge. Talk to your doctor, pharmacist and specialist healthcare team for lifestyle advice and where to get support if this would be helpful.

If you do gain weight, most of this is likely to occur in the first six months of treatment. It is possible you may continue to gain weight after this time, but the rate of weight gain will usually be slower. This can happen even if you are taking a very low dose.

Quetiapine can also affect the way your body processes sugar. A side effect of quetiapine includes high blood sugar and, while not common, has been linked to the development or worsening of diabetes in some young people. This could also be linked to putting on weight.

It is important to watch out for symptoms that might mean your body is having trouble processing sugar. These include wanting to drink a lot, going for a wee a lot, and feeling very weak or tired all the time. If you develop these symptoms, or any other symptoms you are concerned about, it is important to make an appointment with your doctor to discuss this.

If you already have diabetes, taking quetiapine may affect your blood sugar levels. Talk to your doctor and check your blood glucose levels regularly if this applies to you. You may have to increase the medication you use for your diabetes.

You may want to let your family and friends know you are taking quetiapine so they can support you and help you look out for side effects.

For guidance on this, check out our page on getting support with your medication.

In the first few days of taking quetiapine, you may feel extremely sleepy.

Reported side effects of quetiapine include strange dreams or nightmares.

Rarely, quetiapine can also cause sleep-talking and sleep-walking. Some people have also done other activities while they were asleep, like eating.

If you have been taking quetiapine for more than a month and you continue to feel very sleepy during the day (or your sleep at night is worse), you should go back to your doctor and discuss what changes could be made to help. This may include switching to a different medication.

Alcohol

It may be possible to drink some alcohol in moderation while taking quetiapine but having the two together might make you very sleepy and unsteady on your feet, especially when you first start taking the medication.

During the first few weeks, it might be best to stop drinking alcohol until you see how the medicine affects you.

If you want to drink alcohol, it’s best to only drink small amounts, and have a plan for getting home safely if you go out.

Drinking alcohol every day, or in large amounts, can make your symptoms worse and may mean you won’t get the maximum benefit from your medication.

Street drugs

Some street drugs like cocaine and ecstasy can increase levels of dopamine in the brain. As antipsychotics block the effects of dopamine, the 'high' from street drugs may not be as 'high' as before. So you may be tempted to increase the dose of your street drug to make up for it, but this could be dangerous.

Cannabis and other drugs may have their own side effects on your mental health, like anxiety or psychosis.

Some street drugs can make you feel sleepy and this could be made worse with quetiapine.

Quetiapine can enhance the effects of some street drugs and has itself been abused for this purpose. Do not share your quetiapine with anyone else. If someone is asking you to give away or sell your medicine, please ask your parent, teacher or doctor to help you.

There are many other street drugs, but we don’t know what effect taking them with quetiapine will have, so it’s best to be cautious. There is no regulation of street drugs or ‘legal highs’, so even if there are no known issues with the medication you take, the supply you receive might be mixed with other substances that could be dangerous.

Get more advice on our drugs and alcohol guide.

Quetiapine does not mix well with some other medicines, including herbal medicines.

Always talk to the doctor if you are taking other medicines. Tell the pharmacist you are taking quetiapine if you buy medicines for common illnesses, including things you put on your skin.

Look at the leaflet inside your medicine box for more information about other medicines that can interact with quetiapine. With some medicines your doctor may need to adjust the dose of quetiapine if you take them together. Ask a doctor or pharmacist for more information if you have any questions.

Do not drink grapefruit juice while you are taking quetiapine, as it can increase the amount of drug absorbed from the gut.

There are multiple companies that manufacture this medicine and the non-active ingredients may vary between products and also between the different strengths of tablets that are available. Always let your pharmacist know if you have any food allergies or intolerances, and always check with them if you’re concerned about any of the ingredients in your medication.

The tablets contain lactose so they may not be suitable for you if you have problems eating some sugars or dairy products.

The oral solution (liquid) contains sucralose. This should not affect your blood sugar if you’re diabetic.

If you need to avoid animal products, please note that non-active ingredients used in the production of medicines may sometimes be of animal origin. Ask your pharmacist if you have any questions about the ingredients.

Further information about practical considerations for medicines if you need to avoid animal products can be found on the Vegan Society website.

Taking quetiapine may make you feel tired or dizzy and may affect your eyesight when you start taking it.

This could affect you if you drive a car, ride a bike, or do anything else that needs a lot of focus. It might be best to stop doing these things for the first few days or weeks until you know how it affects you.

Most people drive as normal while taking quetiapine. If you are worried about this or have any concerns you would like to discuss, speak to your doctor or pharmacist.

You must tell The DVLA (Driver and Vehicle Licensing Agency) if you have bipolar disorder, schizophrenia, schizoaffective disorder or other mental health conditions that could affect your driving. You can be fined if you do not tell DVLA about a medical condition that affects your driving and may be prosecuted if you are involved in an accident as a result.

Pregnancy

If you become pregnant while you are on quetiapine, you should carry on taking it and make an appointment to see your doctor as soon as possible. They can discuss the benefits and risks of continuing quetiapine and help you to make a decision that is best for you and your baby.

They may refer you to a specialist perinatal mental health team to support you with this decision.

You can find out more information about taking quetiapine during pregnancy at Bumps (Best Use of Medicines in Pregnancy).

Untreated illness can also be harmful to you and your developing baby, so decisions about stopping or avoiding medication when you are pregnant need to be discussed carefully with your doctor. If you and your doctor agree that it is best for you to continue taking quetiapine while pregnant, you should tell your midwife. If you are planning to get pregnant, it is recommended that you take folic acid while you are trying for a baby and during pregnancy. It is safe to take this together with quetiapine.

Quetiapine can slightly increase your chance of getting high blood pressure in pregnancy (pre-eclampsia), gaining weight and gestational (pregnancy-linked) diabetes. Let your midwife know you are taking quetiapine so they can monitor you during pregnancy and birth.

Blood clots are also a rare side effect of taking quetiapine. To reduce your risk of a blood clot, your doctor of midwife might suggest using a medicine to prevent this.

Post-natal

If quetiapine is taking in the last three months of pregnancy, there can be symptoms the baby is born with. They are usually mild and don’t last long. But speak to your doctor or midwife if your baby has feeding difficulties, is restless or has breathing problems.

Breastfeeding

Quetiapine is passed to the baby in breastmilk in small amounts.

If your baby was born early, then breastfeeding while you are taking quetiapine may not be recommended. Talk to your midwife and doctor about feeding options.

If you breastfeed whole taking, seek urgent medical advice if your baby becomes restless, very sleepy or developing feeding problems.

Sex

Quetiapine can have side effects that might affect your sex life. Although they are very, they include:

not feeling like you want to have sex
swelling of the breasts and (very rarely) some milk flow, regardless of gender
changes to your period
getting a painful erection that could last a long time (priapism). If this happens, go to hospital for treatment.

Untreated mental illness can have a negative effect on your sex life, so if quetiapine helps you to recover, positive effects can include improving your desire, experience and enjoyment of sex as your mood lifts and you become interested in life and relationships again.

Fertility

There is currently no evidence to show that quetiapine will affect your fertility.

It can increase a naturally occurring hormone in your body called prolactin. If you have raised levels of prolactin this can impact your fertility, no matter your gender. For people who menstruate, it may cause your periods to stop or become irregular. This can make getting pregnant harder.

Let your doctor know if you’re planning on getting pregnant and taking quetiapine. They can monitor your prolactin levels.

Quetiapine is not a banned substance in sport. However, it can produce a false positive result in some drug tests, including urine tests for methadone. Talk to your doctor about this if it is a problem for you.

Most people play sports as normal while taking quetiapine, but if quetiapine affects your concentration, eyesight or co-ordination, then you may want to wait to see if those effects go away before playing sports that need a lot of focus. If you have any concerns, discuss this with your doctor.

Quetiapine may affect your concentration, give you blurred eyesight and make you feel dizzy and tired.

Ideally it is best not to take quetiapine for the first time just before your exams.

It is not possible to predict how the medication will make you feel, and if you do get any side effects, these are more likely to occur when you first start taking quetiapine.

You should talk to your doctor about any future exams if you are starting quetiapine. You might decide together to delay starting it until you have done them.

If they are more than a month away, however, you might find that it is better to start quetiapine to improve your motivation and ability to study.

Most people take exams as normal while taking quetiapine, but if you have any concerns, discuss this with your doctor.

Information and safety considerations

Your doctor will consider any other medical conditions or symptoms you have before recommending a medicine for you.

Your medicine will come with a ‘patient information leaflet’. It’s important that you read this information. Speak to your pharmacist if:

you’re not given a leaflet
you don’t understand the information
you need it in a different format or language
you’re concerned about something you’ve read

The information leaflet also includes a list of warnings and precautions to consider before you take the medicine. If you think that any of these apply to you and are concerned that your doctor is not already aware of them, check with your doctor or pharmacist before you start to take your medication (or as soon as possible if you are already taking it).

Uses, warnings, safety and side effects

Taking quetiapine

Your doctor will advise you on how long it is best to keep taking your medication. This may vary depending on what you’re taking it for and how many times you’ve been unwell.

If it is prescribed for psychotic symptoms or schizophrenia, it is recommended that you take this medication for at least six months to two years after your first episode of illness. It may be appropriate to continue for longer if you had more than one episode of illness.

If you are taking quetiapine to treat bipolar mania or depression, then you will need to discuss long-term medicines for your bipolar disorder with your doctor. This is to help stop the illness coming back.

For bipolar disorder, it is important to remain on medicines in the long term because every time you become ill, there is more chance of you becoming ill again. Quetiapine can be used as a long-term medicine, but there are other choices too. You should discuss your options with your doctor.

For schizoaffective disorder, it is probably best to keep taking quetiapine for several years to reduce the chances of the illness coming back. We know less about schizoaffective disorder, but it has some similarities to bipolar disorder and some similarities to schizophrenia.

If you are taking quetiapine to help with feelings and emotions, like severe agitation, irritability or aggression, your doctor will review your medication with your regularly.

You will get most benefit from your quetiapine if you take it every day at the dose prescribed by your doctor.

You will start with a low dose that your doctor will increase slowly to a dose that is effective for you. This may take several days or weeks.

You will usually take your dose once or twice a day.

It doesn’t matter what time you take it each day but try to take it at about the same time each day. Choose a time that you can always remember. This could be a mealtime or when you brush your teeth.

You can take the ordinary tablets with or without food and they should be swallowed with a drink of water – the tablets have an unpleasant bitter taste if chewed.

The prolonged-release (long-acting) tablets should not be broken as they have a special system in them to deliver the medicine into your body slowly over a few hours.

You should take the prolonged-release (long-acting) tablets by swallowing them whole with a glass of water on an empty stomach one hour before food, or two hours after food. Do not chew or crush the tablets.

The liquid comes with an oral syringe and dosing cup to help you measure the correct dose. Shake the bottle well before use. The liquid should be stored in a fridge. It has an expiry date of 28 days after you open the bottle.

If you remember later during the day, take it as soon as possible.

If you forget to take it by your next dose, just take the next dose at the correct time. Do not try to catch up on missed doses by taking a double dose.

If you forget to take your tablets for a few days, you may start getting your old symptoms back or some withdrawal symptoms. Talk to your doctor if this happens.

Regularly forgetting to take your medication can increase the risk of you becoming ill again and may mean that your symptoms could be worse if you become unwell again.

If you are struggling to remember to take your medication regularly as prescribed by your doctor, speak to your pharmacist and doctor for advice to help you.

Stopping quetiapine too soon after you have recovered may increase your risk of becoming unwell again. Discuss stopping your medication with your doctor. Planning and support are important to stopping quetiapine successfully.

Quetiapine is not addictive, but if stopped suddenly, or the dose you are taking is reduced too much at once, you may experience withdrawal symptoms. These are caused by the receptors and levels of chemical transmitters in your brain readjusting after you reduce or stop your medication. Your brain can take a while to adapt to this change.

Some of the symptoms you get may be like symptoms you had when you were unwell, so understandably, you might feel anxious or upset that your illness could be returning.

Withdrawal symptoms usually start within a few days of stopping (or sometimes reducing) your medication. A wide range of symptoms have been reported. You may experience a few or a range of these:

difficulty getting to sleep or disturbed sleep
low mood, feeling anxious or agitated or restless
dizziness or light-headedness
headaches
reduced concentration or feeling confused
feeling sick or being sick, diarrhoea
flu-like symptoms
tense or jerky muscles and slow movements
uncontrollable movement of face or body
hallucinations, intrusive thoughts (you may experience these even if your medication wasn’t prescribed to treat psychosis)

It is not possible to predict if you will experience withdrawal symptoms, or how bad they will be if you do experience them. If you do experience symptoms, they are usually mild and don’t last long, but for some these could be severe enough to make you feel very unwell and last longer (two to three months or more). Arrange an appointment with your doctor to discuss your symptoms and seek advice if you are concerned or unable to tolerate them.

Some people have thoughts about harming themselves or taking their own lives soon after they stop this medicine. If you have any thoughts like this, it is important you get urgent help. Contact your doctor immediately for advice and support. This could be your GP or specialist mental health team. If you are able, share how you are feeling with family member or friend as well so they can support you to get help. You may have discussed what to do if you got these thoughts with your doctor when starting this medicine and created a safety plan. Reading this may also be helpful to remind you about who to contact for support and what you can do to help you cope.

You can stop taking quetiapine safely with your doctor’s help. Planning a gradual withdrawal together can help to minimise or prevent the withdrawal symptoms you experience.

Warnings and safety

If you have taken more than the dose prescribed by your doctor, contact NHS 111 immediately to ask for advice, or ask a family member or friend to do this for you. This is important even if you don’t feel any different.

NHS 111 can give you advice and direct you to the best place to get more help if you need it.

If you have taken too much medication on purpose, or if after taking this you quickly feel unwell, call 999 or get someone to take you to A&E straight away. This includes any of the following signs:

feeling sleepy or tired
unusual body movements you can’t control
problems standing and walking
feeling dizzy (due to low blood pressure)
uneven heartbeat
seizures or fits

If you need to go to A&E, do not travel alone or drive yourself there. Get your parent, family member or friend to go with you to support you and keep you safe on the way. If someone is not able to drive you there, call for an ambulance. Take your medication with you and tell doctors how much you have taken.

Suicidal thoughts

While taking quetiapine you may have thoughts about hurting yourself or taking your own life. These thoughts could be caused by mental illness or maybe a side effect of your medicine. They have been reported during treatment with quetiapine or soon after stopping treatment.

If you have any thoughts like this, it is important you get urgent help. Contact your doctor immediately for advice and support. This could be your GP or specialist mental health team. If you are able, share how you are feeling with family member or friend as well so they can support you to get help.

If you discussed with your doctor what to do if you get these thoughts and created a safety plan, read this to remind you who to contact for support and what you can do to help you cope.

Read our guide to suicidal feelings

Serious side effects

Quetiapine can sometimes cause serious side effects, including allergic reactions.

Stop taking quetiapine and go to a hospital straight away if you get any of the following symptoms:

difficulty breathing
an allergic reaction or allergy (including symptoms such as swelling of your face, eyelids, lips, tongue or throat so that you cannot swallow or breathe, or really bad itching of the skin with raised lumps)
fever, muscle stiffness, sweating or reduced consciousness (these symptoms could be caused by neuroleptic malignant syndrome)
seizures or fits
a painful erection (priapism) that lasts longer than three hours

Get your parent, family member or friend to take you or go with you to support you and keep you safe on the way. If someone is not able to drive you there, call for an ambulance. Take your medication with you.

Contact your doctor immediately but don't stop taking quetiapine, if you get any of the following symptoms:

movements of the tongue, mouth and face that you cannot control (this could be a condition called tardive dyskinesia)
tensing or contraction of muscles that you are not able to control (this could affect any muscle, including your eyes, mouth, tongue or jaw)
any unusual bleeding or bruising
sudden fever, sore throat or mouth ulcers
swelling, pain, and redness in the leg (this could be a blood clot and may lead to chest pain and difficulty breathing)
yellowing of the skin or whites of the eyes (these may be signs of hepatitis)
a sudden change in your mental state, or difficulty with your memory
severe abdominal pain and feeling sick
develop new symptoms including needing to drink a lot, needing to pee a lot, feeling weak or increased appetite and feeling hungry (these might indicate your body is not processing sugar very well)

Feeling a little dizzy or sleepy is common, particularly at the start of treatment. This usually passes, but if you feel very dizzy or excessively sleepy, contact your doctor.

If you are unable to contact your doctor, call NHS 111 for urgent advice.

Side effects and your health

Side effects are more common when you first start taking quetiapine. Many go away as you continue your medicine. If they don’t get better, or if you are worried by them and they are causing you distress, speak to your doctor or pharmacist about them.

Very common side effects of quetiapine (affecting more than one in ten people) include:

dizziness, which may lead to falls
headache
dry mouth
feeling sleepy
weight gain
unusual muscle movements

Common side effects of quetiapine (affecting up to one in ten people) include:

feeling like your heart is pounding, racing or skipping beats
indigestion or constipation (having difficulty pooing)
feeling weak
swelling of the arms or legs
high blood sugar
blurred vision
unusual dreams or nightmares
increased appetite
disturbances in speech or language
thoughts of suicide or worsening of your depression
shortness of breath
being sick (mainly in older people)

Young people are more likely than adults to get the following side effects:

having thoughts about hurting themselves or taking their own lives
increased appetite
higher blood pressure
movement disorders
higher levels of the hormone prolactin in the blood
feeling irritable

There are other side effects that you can get when taking this medicine. We have only included the most common ones here.

This list of side effects can look scary. You may not experience any of them, but it’s important to be aware of them so you know what to do if they do happen.

Unless your side effects are very severe or distressing, try to continue taking your medication until you can talk to your doctor. Your doctor can make changes to your medication to help if needed.

You should have your weight, blood sugar, blood fats, prolactin level, blood pressure and pulse measured before you start quetiapine and regularly during early treatment, then at least every six months (if you are under 18) or once a year (if you are over 18) after that.

A blood test will be required to check your blood sugar, blood fats and prolactin level.

Your doctor might also recommend additional monitoring. This might include checking your heart with an electrocardiogram (ECG) and checking your liver and thyroid function. This is done by taking a blood test.

They might also check your height and development. If you have periods, they may ask if there have been any changes to the pattern or frequency of these.

It is very important to go for these checks when you are asked to do so. If you are worried or anxious about the monitoring, talk to your doctor, care team or practice nurse about this for advice and support.

You could take some of these measurements at home (e.g. weight ) and keep a record of the results to share with your doctor when they review your treatment.