Quetiapine - Use | Dose | Side Effects

Quetiapine (also known as SEROquel) belongs to the group of medicines known as antipsychotics. These medicines improve symptoms of certain types of mental diseases such as:

  • Hallucinations (if for example, you hear unexplained voices), a strange and disturbing thoughts, changes in behavior, loneliness and confusion.
  • A mood disorder in which a patients feels overly excited or upset. People with this condition can be established that they require less sleep than usual, they are talkative, and have the rapid flow of thoughts and ideas. Nonetheless, they can felt extremely irritated.
  • A mood disorder in which a patients feels overly sad (depressed) all the time, feel guilty, feel that they have less energy, have lost their appetite and can not sleep.

Your doctor may order further treatment, and when you 're feeling better, because it reduces possibility of returning symptoms of your disease. It can be useful if your treatment include your family and friends. Ask them to read this and help in monitoring signs of disease and medicine treatment.

Warning and precautions

Do not take quetiapine (Seroquel):

  • If you are allergic (hypersensitive) to quetiapine.
  • If you are taking any of the following medications:
    • Some medicines used to treat HIV (e.g., nelfinavir, ritonavir, saquinavir)
    • Medicines from among the azoles (for the treatment of fungal infections)
    • Erythromycin, clarithromycin, or (for the treatment of infection)
    • Nefazodone (for treating depression).

If any of the above apply to you, do not take quetiapine (Seroquel). If you have any doubts, before taking the medication, contact your doctor or pharmacist.

Be careful with the medicine quetiapine (Seroquel):

Elderly people with dementia (people with severely impaired brain function ) should not take quetiapine (Seroquel). The reason is that a group of medicines that includes quetiapine (Seroquel), in demented elderly may increase the risk of stroke, and in some cases the risk of death.

Inform you doctor

  • if you have any heart problems or low blood pressure;
  • if you have suffered a stroke, especially if you're already in the elderly age;
  • if you have liver problems;
  • if you have or ever had an epileptic seizure;
  • if you have diabetes or are at risk of that disease. If this is the case, during the treatment, your doctor may check the level of sugar in your blood;
  • if you have a history of low levels of white blood cells (which may or may not have been caused by the use of other medicines)
  • if you have a high levels of cholesterol or triglycerides;
  • if you have a cataracts.

Other notes:

Thoughts of harming and worsening of symptoms People suffering from depression and/or anxiety disorders can sometimes think about how to harming themselves or suicide. This may be particularly expressed when patients are first time taking medication for the treatment of mental illness, because these medicines take some time to work. People who are prone to thinking about harming or killing, are those who are already try to hurt themselves, and patients under 25 years. It has been shown that there is an increased risk of suicidal behavior in young adults with psychiatric disorders, which are suffering from depression. If at any time you start thinking to harm or take away life, you should contact your doctor or go to the nearest hospital! If you think that it might be useful, tell a friend or relative that you are depressed or have an anxiety disorder. Ask them to read this and warns you if they notice that a disease state deteriorated or are concerned about changes in your behavior.

Use with other medicines (Interactions)

Warn your doctor if you use any of the following medications:

  • medicines for the treatment of depression and anxiety
  • medicines for the treatment of epilepsy (such as phenytoin and carbamazepine)
  • medicines for the treatment of high blood pressure (antihypertensive) and heart rhythm disorder such as: amiodarone, flecainide, droneradone, disopyramide, procainamide, sotalol, quinidine etc.
  • rifampicin (used to treat tuberculosis)
  • barbiturates (medicines for sleep problems) such as: phenobarbital
  • thioridazine, ziprasidone, pimozide, iloperidone etc (also an antipsychotic)
  • anticancer medicines such as: nilotinib, toremifene, vandetanib, arsenic trioxide, vemurafenib etc.

Before you stop taking any of the medications you normally take, talk to your doctor.

Taking with food and drink

Quetiapine (Seroquel) can be taken without regard to food.  You should not take alcohol during treatment with this medicine because you may be sleepy. During treatment, do not drink grapefruit juice, because it may have a negative affect on the mechanisms action of the medicine, thereby jeopardizing its effectiveness.

Pregnancy and breast-feeding

Tell your doctor if you are pregnant or trying to get pregnant, or if you are breast-feeding, before you start taking quteiapine (Seroquel).

Driving and using machines

Quetiapine (Seroquel) may cause sleepiness. Do not drive and do not operate any tools or machines while you are taking this medicine.

Dosage and administration

Always take medication as directed by your doctor. If you are not sure how to take your medicine, contact your doctor or pharmacist. Your doctor will decide on the initial dose of the medicine, which can gradually be increased, and the number of tablets to be taken on the day. This will depend on your illness and needs, but daily dose will typically range between 150 and 800 mg. You will take your tablets once a day (in the evening before bedtime) or twice daily, depending on your disease. Do not halve the tablet, chew or crumble. Swallow the tablets whole with some water. Quetiapine (Seroquel) can be taken with a meal or on an empty stomach.


Your doctor can begin treatment with a lower dose of the quetiapine, and gradually increased up.

Patients with liver disease

Your doctor can begin treatment with a lower dose of the quetiapine, and gradually increased up.

Children and teens

Quetiapine (Seroquel) is not recommended for people younger than 18 years. Even if you feel better, do not stop taking the quetiapine until you are instructed to do so, by your doctor recommends.


If you take more quetiapine (Seroquel) than you were prescribed by your doctor, you can feel the drowsiness, dizziness and irregular heartbeat. In these circumstances, immediately contact your doctor or the nearest hospital. Bring your box with pills.

If you forget to take quetiapine (Seroquel)

If you forget to take medicine, take it as soon as you remember. Do not take two doses of the medicine per day, or double dose to make up for.

If you stop taking quetiapine (Seroquel)

If you decide to stop your treatment, always prior consult to your doctor. If you suddenly stop taking this medicine, you may have insomnia, nausea, or you suffer from headaches, diarrhea, vomiting, dizziness, or be irritable. Before your treatment is completely cancel, your doctor may advise you to gradually reduce the dose, until complete cessation of taking quetiapine (Seroquel). If you have any further questions on the use of quetiapine (Seroquel), contact your doctor or pharmacist.

Side effects

Common side effects (occurring in about 1 in 100 people):

  • convulsions (epileptic seizures similar)
  • allergic reaction accompanied by a red, bulging skin rash, swelling of eyelids, face, lips, mouth or tongue, itching, difficulty breathing or swallowing
  • uncontrolled movements, especially of the face and tongue.

Rare side effects (occurring in about 1 in 10 000 people)

  • high body temperature (fever), long-term inflammation of the throat or ulcers in the mouth, rapid breathing, sweating, muscle stiffness, feeling of extreme stupor or unconsciousness, significant increase in blood pressure and heart rate
  • yellowing of the skin or eyes (jaundice)
  • prolonged and painful erection (priapism)
  • blood clots such as deep vein thrombosis of the legs or in the lungs, which can cause chest pain and difficulty breathing

Very rare side effects (affects less than 1 in 10 000 people)

  • severe allergic reaction (called anaphylaxis), which can make it difficult to breathe or cause shock;
  • inflammation of the liver (hepatitis);
  • rapid swelling of the skin, usually around the eyes, lips and the area of the throat (angioedema).

Other possible side effects

Very common side effects (occurring in more than 1 in 10 people)

  • dizziness, headache, dry mouth;
  • sleepiness (which while taking the medicine may disappear);
  • withdrawal symptoms (symptoms that occur when you stop taking the medicine), and include: insomnia, nausea, headache, diarrhea, vomiting, dizziness and irritability (listed symptoms usually disappear after a week when is taken the last dose);
  • weight gain.

Common side effects (occurring in about 1 in 100 people)

  • rapid heartbeat
  • stuffy nose
  • constipation, stomach upset (indigestion)
  • feeling of weakness, fatigue
  • swelling of the arms or legs
  • low blood pressure when standing up. This may be the reason why you feel dizzy or fainting
  • elevation of blood sugar levels
  • blurred vision
  • abnormal muscle movements (difficulties in initiating muscle activity, tremors, feeling restlessness or painless muscle stiffness)
  • restless dreams and nightmares
  • increased hunger
  • irritability
  • difficulty in speech

Uncommon side effects (occurring in about 1 in 1,000 people)

  • uncomfortable feeling in the legs (also called restless leg syndrome)
  • difficulty swallowing

Rare side effects (occurring in about 1 in 10 000 people)

  • swelling breasts and unexpectedly secretion of milk (women and men)
  • absence or irregular menstrual

Very rare side effects (affects less than 1 in 10 000 people)

  • worsening of pre-existing diabetes mellitus
  • severe rash, blisters or red spots on the skin

Some of side effects can be observed only if you do a blood test. This involves an increase in specific fat (triglyceride and total cholesterol) and the blood sugar as well as reduction in the number of certain types of blood cells and increase levels of the hormone prolactin in the blood. Your doctor may ask you to occasionally do a blood tests. If you notice any side effects please tell your doctor or pharmacist.

Children and adolescents (10 to 17 years)

The side effects listed in adults may also occur in children and adolescents. The following listed side effects were observed only in children and adolescents:

Very common side effects (occurring in more than 1 in 10 people)

  • increase in blood pressure

The following listed side effects have been reported more frequently in children and adolescents:

Very common side effects (occurring in more than 1 in 10 people)

  • increase levels of the hormone prolactin in the blood which in rare cases can lead to swelling breast and unexpected secretion of milk (girls and boys) and the absence or irregular menstruation in girls
  • increased appetite
  • abnormal muscle movements ( difficulties in initiating muscle activity, tremors, painless muscle stiffness).

Information on this website are provided for educational purposes only and are not intended for medical advice, diagnosis or treatment.

If you have any concerns or questions about your health, you should always consult with a physician or other health-care professional.