Quetiapine belongs to a group of medicines called antipsychotics.
Keep your regular appointments with your doctor. This is so your progress can be checked.
The most common side-effects include feeling sleepy or dizzy, headache, and increased weight.
Do not drink alcohol or grapefruit juice.
|Type of medicine||An antipsychotic medicine|
|Used for||Easing the symptoms of schizophrenia; mood disorders associated with bipolar disorder|
|Also called||Seroquel®; Atrolak® XL; Biquelle® XL; Brancico® XL; Mintreleq® XL; Seroquel® XL; Sondate® XL; Zaluron® XL|
|Available as||Standard-release tablets and prolonged-release tablets|
Quetiapine belongs to a group of medicines called antipsychotics. It may have been prescribed for you to relieve the symptoms of schizophrenia or, alternatively, for a mood disorder such as mania or depression. In all of these conditions, quetiapine works on the balance of chemical substances in your brain.
Quetiapine is available as standard-release tablets (which are generally taken twice daily) and also as modified-release tablets (which are taken once daily). Modified-release tablets have the letters 'XL' after the brand name - these release quetiapine more slowly and evenly throughout the course of the day.
Before taking quetiapine
Some medicines are not suitable for people with certain conditions, and sometimes a medicine may only be used if extra care is taken. For these reasons, before you start taking quetiapine it is important that your doctor knows:
- If you are pregnant or breastfeeding.
- If you have a heart condition or blood vessel disease.
- If you have had a stroke, or if you have been told you have 'thickening' of the blood vessels to your brain.
- If you have liver, kidney, or prostate problems.
- If you have any problems with your breathing, or if you have any difficulties swallowing.
- If you have breathing difficulties whilst sleeping (sleep apnoea).
- If you have any of the following: epilepsy, Parkinson's disease, raised pressure in your eye (glaucoma) or a condition which causes muscle weakness, called myasthenia gravis.
- If you have ever had yellowing of your skin or of the whites of your eyes (jaundice) or a blood disorder.
- If you have a tumour on your adrenal gland (a condition called phaeochromocytoma).
- If you have had problems with alcohol or drug abuse.
- If you have had an allergic reaction to a medicine.
- If you are taking or using any other medicines. This includes any medicines you are taking which are available to buy without a prescription, as well as herbal and complementary medicines.
How to take quetiapine
- Before you start the treatment, read the manufacturer's printed information leaflet from inside the pack. It will give you more information about quetiapine and it will also provide you with a full list of the side-effects which you may experience from taking it.
- Take quetiapine exactly as your doctor tells you to. It is taken once or twice a day depending upon the type of tablet prescribed. There are several different strengths of tablet available so your doctor will prescribe a dose to suit your condition. The directions for taking the tablets will be printed on the label of the pack to remind you about what the doctor said to you.
- Try to get into the habit of taking your doses at the same times of day each day, as this will help you to remember to take them regularly. If you are taking quetiapine for depression, you should take your doses at bedtime.
- Standard-release quetiapine tablets (these are usually taken twice daily) can be taken either before or after meals.
- If you have been given prolonged-release tablets (these have the letters 'XL' after the brand name) you must swallow the tablet whole when your stomach is empty. This means that you should not chew or break the tablet before your swallow it, and that you should take each of your doses at least an hour before a meal, or wait until two hours afterwards.
- Do not drink grapefruit juice while you are on quetiapine. This is because a chemical in grapefruit is likely to increase the amount of quetiapine in your bloodstream and make side-effects more likely.
- If you forget to take a dose, take it as soon as you remember unless it is nearly time for your next dose, in which case leave out the forgotten dose. Do not take two doses together to make up for a missed dose.
Getting the most from your treatment
- Your treatment will require careful monitoring to make sure that you get the best possible benefit from quetiapine. Keep your regular doctor's appointments so that your progress can be checked. You will need to have some tests from time to time.
- Quetiapine tablets come in different strengths and colours. If your dose is changed, your tablets may look different. If you are unsure about your tablets at any time, please ask your pharmacist for advice.
- Treatment with quetiapine is usually long-term unless you experience an adverse effect. Keep taking the tablets unless your doctor tells you otherwise. Stopping quetiapine suddenly can cause problems so your doctor may want you to reduce your dose gradually if this becomes necessary.
- If you drink alcohol, ask your doctor for advice. Alcohol increases the risk of side-effects from quetiapine so it is best avoided.
- If you have diabetes you may need to check your blood glucose more frequently, as quetiapine may affect the levels of sugar in your blood. Your doctor will advise you about this.
- Some medicines similar to quetiapine can cause the skin to become more sensitive to sunlight than normal. It may be advisable to use a sunscreen in bright sunlight until you know how your skin reacts.
- If you are due to have any medical or dental treatment, tell the person carrying out the treatment which medicines you are taking. This is important because quetiapine may interfere with any anaesthetic you receive.
- If you buy or take any 'over-the-counter' medicines or herbal remedies, please check with a pharmacist that they are suitable for you to take with quetiapine.
- A small number of people taking medicines for mood disorders can have thoughts about harming themselves or ending their lives, particularly when a new medicine is started. It is very important that you tell your doctor about this if it happens to you.
Can quetiapine cause problems?
Along with their useful effects, most medicines can cause unwanted side-effects although not everyone experiences them. The table below contains some of the most common ones associated with quetiapine. You will find a full list in the manufacturer's information leaflet supplied with your medicine. The unwanted effects often improve as your body adjusts to the new medicine, but speak with your doctor or pharmacist if any of the following continue or become troublesome.
|Very common quetiapine side-effects (these affect more than 1 in 10 people)||What can I do if I experience this?|
|Changes to the results of some blood tests||Your doctor will check for these|
|Headache||Drink plenty of water and ask your pharmacist to recommend a suitable painkiller. If the headaches continue, let your doctor know|
|Feeling dizzy or light-headed when you stand up||This can happen particularly when you first start taking quetiapine. Getting up more slowly until you are aware how you react should help|
|Feeling sleepy or drowsy||Do not drive and do not use tools or machines. Avoid alcohol|
|Increased weight, dry mouth||Speak with your pharmacist if troublesome|
|Feeling restless or shaky, unusual or uncontrollable muscle movements||Speak with your doctor about any of these. Your treatment may need adjusting|
|Common quetiapine side-effects (these affect less than 1 in 10 people)||What can I do if I experience this?|
|Indigestion, feeling sick (nausea) or being sick (vomiting)||Stick to simple meals - avoid rich or spicy foods|
|Constipation||Eat a well-balanced diet and drink several glasses of water each day|
|Blurred vision||Do not drive and do not use tools or machines|
|Feeling tired, increased appetite, abnormal dreams, having a feeling that your heart is pounding (palpitations), feeling short of breath, swollen feet or ankles, feeling irritable||If any of these become troublesome, speak with your doctor|
Important: if you experience symptoms such as muscle stiffness, a very high temperature, feeling confused, a fast heartbeat and sweating, you should contact your doctor immediately. These can be signs of a rare but serious condition known as neuroleptic malignant syndrome.
If you experience any other symptoms which you think may be due to the tablets, please speak with your doctor or pharmacist for further advice.
How to store quetiapine
- Keep all medicines out of the reach and sight of children.
- Store in a cool, dry place, away from direct heat and light.
Important information about all medicines
Never take more than the prescribed dose. If you suspect that you or someone else might have taken an overdose of this medicine, go to the accident and emergency department of your local hospital. Take the container with you, even if it is empty.
This medicine is for you. Never give it to other people even if their condition appears to be the same as yours.
Do not keep out-of-date or unwanted medicines. Take them to your local pharmacy which will dispose of them for you.
If you have any questions about this medicine ask your pharmacist.
Further reading and references
Manufacturer's PIL, Seroquel® 25 mg, 100 mg, 150 mg, 200 mg, 300 mg film-coated tablets; AstraZeneca UK Limited, The electronic Medicines Compendium. Dated May 2016.
Manufacturer's PIL, Seroquel® XL, 50 mg, 150 mg, 200 mg, 300 mg, 400 mg prolonged-release tablets; AstraZeneca UK Limited, The electronic Medicines Compendium. Dated May 2016.
British National Formulary, 75th Edition (Mar 2018); British Medical Association and Royal Pharmaceutical Society of Great Britain, London.