QUETIAPINE (Systemic)
Some commonly used brand names are:
In the U.S.?
Category
Description
Quetiapine (kwe-TYE-a-peen) is used to treat psychotic disorders, such as schizophrenia.This medicine has NOT been approved to treat behavioral problemsin older adult patients who have dementia.
Quetiapine is available only with your doctor's prescription, in the followingdosage form:
Oral- Tablets (U.S. and Canada)
Before Using This Medicine
In deciding to use a medicine,the risks of taking the medicine must be weighed against the good it willdo. This is a decision you and your doctor will make. For quetiapine, thefollowing should be considered:
Allergies?Tell your doctor if you have ever had any unusual orallergic reaction to quetiapine. Also tell your health care professional ifyou are allergic to any other substances, such as foods, preservatives, ordyes.
Pregnancy?Quetiapine has not been studied in pregnant women.However, studies in rats and rabbits have shown that quetiapine at doses higherthan the highest human dose causes reduced weight and other problems in thefetus. Before taking this medicine, make sure your doctor knows if you arepregnant or if you may become pregnant.
Breast-feeding?Quetiapine has been shown to pass into the milkof animals. It is not known whether this medicine passes into breast milk.However, quetiapine is not recommended for use during breast-feeding, becauseit may cause unwanted effects in nursing babies. Be sure you have discussedthe risks and benefits of the medicine with your doctor.
Children?Studies on this medicine have been done only in adultpatients, and there is no specific information comparing use of quetiapinein children with use in other age groups.
Older adults?This medicine has been tested in a limited numberof patients 65 years of age or older and has not been shown to cause differentside effects or problems in older people than it does in younger adults. However,quetiapine may be removed from the body more slowly in older adults, so anolder adult may receive a lower dose than a younger adult. This medicine hasNOT been approved to treat behavioral problems in older adults with dementia.
Other medicines?Although certain medicines should not be usedtogether at all, in other cases two different medicines may be used togethereven if an interaction might occur. In these cases, your doctor may want tochange the dose, or other precautions may be necessary. When you are takingquetiapine, it is especially important that your health care professionalknow if you are taking any of the following:
- Alcohol (with chronic use) or
- Barbiturates or
- Carbamazepine (e.g., Tegretol) or
- Griseofulvin (e.g., Fulvicin) or
- Phenylbutazone (e.g., Butazolidin) or
- Phenytoin (e.g., Dilantin) or
- Primidone (e.g., Mysoline) or
- Rifampin (e.g., Rifadin) or
- Saquinavir (e.g., Invirase) or
- Troglitazone (e.g., Rezulin)?These medicines may cause lowerblood levels of quetiapine; the dose of quetiapine may need to be changedif one of these medicines is started or stopped during treatment with quetiapine
- Central nervous system (CNS) depressants (medicines that cause drowsiness)or
- Tricyclic antidepressants (medicine for depression)?Quetiapinemay increase the CNS depressant effects of these medicines, such as drowsiness
- Clarithromycin (e.g., Biaxin) or
- Diltiazem (e.g., Cardizem) or
- Erythromycin (e.g., E-Mycin, E.E.S.) or
- Fluconazole (e.g., Diflucan) or
- Itraconazole (e.g., Sporanox) or
- Ketoconazole (e.g., Nizoral) or
- Nefazodone (e.g., Serzone) or
- Verapamil (e.g., Calan)?These medicines may cause higher bloodlevels of quetiapine, increasing the chance of side effects
Other medical problems?The presence of other medicalproblems may affect the use of quetiapine. Make sure you tell your doctorif you have any other medical problems, especially:
- Alzheimer's disease?Quetiapine may cause problems with swallowing,which may increase the chance of pneumonia; also, the chance of seizures maybe increased
- Breast cancer, or history of or
- Underactive thyroid?Quetiapine may make these conditions worse
- Dehydration?Decreased blood pressure caused by quetiapine maybe more severe; chance of developing heatstroke may be increased
- Heart disease or
- Stroke, or history of?Decreased blood pressure caused by quetiapinemay be more severe or may make these conditions worse
- Kidney disease (severe) or
- Liver disease?Higher blood levels of quetiapine may occur,increasing the chance of side effects; the dose may need to be changed
- Seizures, or history of?Chance of seizures may be increased
Proper Use of This Medicine
Take this medicine only as directed by your doctor to benefit yourcondition as much as possible. Do not take more or less of it and do not takeit more or less often than your doctor ordered.
Quetiapine may be taken with or without food on a full or empty stomach.However, if your doctor tells you to take it a certain way, take it as directed.
Dosing?The dose of quetiapine will be different fordifferent patients. Follow your doctor's orders or thedirections on the label. The following information includes only theaverage doses of quetiapine. If your dose is different,do not change it unless your doctor tells you to do so.
The number of tablets that you take depends on the strength of the medicine.Also, the number of doses you take each day, the timeallowed between doses, and the length of time you take the medicine dependon the medical problem for which you are taking quetiapine.
- For oral dosage form (tablets):
- For schizophrenia:
- Adults?At first, 25 milligrams (mg) two times a day. The doseusually is increased to 300 to 400 mg a day, which is divided and given intwo or three doses a day. Your doctor may increase your dose further, if needed.However, the dose usually is not more than 800 mg a day.
- Children?Use and dose must be determined by the doctor.
Missed dose?If you miss a dose of quetiapine, take it as soonas possible. However, if it is almost time for your next dose, skip the misseddose and go back to your regular dosing schedule. Do not double doses.
Storage?To store this medicine:
- Keep out of the reach of children.
- Store away from heat and direct light.
- Do not store in the bathroom, near the kitchen sink, or in otherdamp places. Heat or moisture may cause the medicine to break down.
- Do not keep outdated medicine or medicine no longer needed. Be surethat any discarded medicine is out of the reach of children.
Precautions While Using This Medicine
Your doctor should check your progress at regular visits,especially during the first few months of treatment with this medicine. Thiswill allow your dosage to be changed if necessary to meet your needs.
This medicine may add to the effects of alcohol andother CNS depressants (medicines that make you drowsy or less alert).Some examples of CNS depressants are antihistamines or medicine for hay fever,other allergies, or colds; sedatives, tranquilizers, or sleeping medicine;prescription pain medicine or narcotics; barbiturates; medicine for seizures;muscle relaxants; or anesthetics, including some dental anesthetics. Check with your doctor before taking any of the above whileyou are using quetiapine.
Quetiapine may cause drowsiness, especially during the first week of use. Make sure you know how you react to this medicine beforeyou drive, use machines, or do anything else that could be dangerous if youare not alert.
Dizziness, lightheadedness, or fainting may occur,especially when you get up from a lying or sitting position. Getting up slowlymay help. If the problem continues or gets worse, check with your doctor.
Quetiapine may make it more difficult for your body to cool down. Use extra care not to become overheated and to drink plentyof fluids during exercise or hot weather while you are taking this medicine. Overheating may result in heatstroke.
Side Effects of This Medicine
Along with its needed effects, quetiapine cansometimes cause serious side effects. Some side effects will have signs orsymptoms that you can see or feel. Your doctor may watch for others, suchas changes in the lenses of the eyes, by doing certain tests. Tardive dyskinesia(a movement disorder) may occur and may not go away after you stop using themedicine. Signs of tardive dyskinesia include fine, worm-like movements ofthe tongue, or other uncontrolled movements of the mouth, tongue, cheeks,jaw, or arms and legs. Another serious but rare side effect that may occuris the neuroleptic malignant syndrome (NMS). You andyour doctor should discuss the good this medicine will do as well as the risksof taking it.
Stop taking this medicineand get emergency help immediately if the following side effects occur:
Rare?Symptoms of NMS; two or more occur together; most ofthese effects do not require emergency medical attention if they occur alone
Convulsions (seizures); difficult or unusually fast breathing; fast heartbeat or irregular pulse; high fever; high or low (irregular) blood pressure; increased sweating; loss of bladder control; severe muscle stiffness; unusually paleskin; unusual tiredness or weakness
Check withyour doctor as soon as possible if any of the following side effects occur:
Less common
Dizziness, lightheadedness, or fainting, especially when gettingup from a lying or sitting position; fever, chills,muscle aches, or sore throat; loss of balance control; mask-like face; shufflingwalk; skin rash; slowedmovements; stiffness of arms or legs; swelling of feet or lower legs; tremblingand shaking of hands and fingers; trouble in breathing,speaking, or swallowing
Rare?Symptoms of underactive thyroid; usually two or moreoccur together; these effects do not require medical attention if they occuralone unless they continue or are bothersome
Dry, puffy skin; loss of appetite; tiredness; weight gain
Symptoms of overdose?May be similar to side effects seen at normal dosesbut may be more severe or two or more may occur together
Drowsiness; fast, slow, or irregularheartbeat; low blood pressure; weakness
Other side effects may occur that usually donot need medical attention. These side effects may go away during treatmentas your body adjusts to the medicine. However, check with your doctor if anyof the following side effects continue or are bothersome:
Other side effects not listed above may also occur in some patients. If younotice any other effects, check with your doctor.
Developed: 02/17/1998
Revised: 08/22/2005
