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|Quetiapine fumarate Quetiapine Fumarate

Quetiapine fumarate

Generic name: Quetiapine fumarate
Brand names: Seroquel

Why is Quetiapine fumarate prescribed?

Quetiapine fumarate is prescribed for the treatment of schizophrenia, a mental disorder marked by delusions (false beliefs), hallucinations, disrupted thinking, and loss of contact with reality. It is also used for the short-term treatment of mania associated with bipolar disorder.

Quetiapine fumarate is the first in a new class of antipsychotic medications. Researchers believe that it works by diminishing the action of dopamine and serotonin, two of the brain"s chief chemical messengers.

Most important fact about Quetiapine fumarate

Quetiapine fumarate may cause tardive dyskinesia, a condition characterized by uncontrollable muscle spasms and twitches in the face and body. This problem can be permanent, and appears to be most common among older adults, especially women.

How should you take Quetiapine fumarate?

Your doctor will increase your dose gradually until the drug takes effect. If you stop Quetiapine fumarate for more than 1 week, you"ll need to build up to your ideal dosage once again.

--If you miss a dose...

Take it as soon as you remember. If it is almost time for the next dose, skip the one you missed and go back to your regular schedule. Do not take 2 doses at once.

--Storage instructions...

Store at room temperature.

What side effects may occur?

Side effects cannot be anticipated. If any develop or change in intensity, inform your doctor as soon as possible. Only your doctor can determine if it is safe for you to continue taking Quetiapine fumarate.

• More common side effects may include:
  Abdominal pain, constipation, diminished movement, dizziness, drowsiness, dry mouth, excessive muscle tone, headache, indigestion, low blood pressure (especially upon standing), nasal inflammation, neck rigidity, rapid or irregular heartbeat, rash, sleepiness, tremor, uncontrollable movements, weakness

Why should Quetiapine fumarate not be prescribed?

If Quetiapine fumarate gives you an allergic reaction, you will not be able to use Quetiapine fumarate.

Special warnings about Quetiapine fumarate

Call your doctor immediately if you develop muscle stiffness, confusion, irregular or rapid heartbeat, excessive sweating, and high fever. These are signs of Neuroleptic Malignant Syndrome (NMS), a serious--and potentially fatal--reaction to the drug. Be especially wary if you have a history of heart attack, heart disease, heart failure, circulation problems, or irregular heartbeat.

Particularly during the first few days of therapy, Quetiapine fumarate can cause low blood pressure, with accompanying dizziness, fainting, and rapid heartbeat. To minimize these effects, your doctor will increase your dose gradually. If you are prone to low blood pressure, take blood pressure medication, or become dehydrated, use Quetiapine fumarate with caution.

Quetiapine fumarate also tends to cause drowsiness, especially at the start of therapy, and can impair your judgment, thinking, and motor skills. Until you are certain of the drug"s effect, use caution when operating machinery or driving a car.

Certain antipsychotic drugs, including Quetiapine fumarate, are associated with an increased risk of developing high blood sugar, which on rare occasions has led to coma or death. See your doctor right away if you develop signs of high blood sugar, including dry mouth, unusual thirst, increased urination, and tiredness. If you have diabetes or have a high risk of developing it, see your doctor regularly for blood sugar testing.

People at high risk of suicide attempts should be prescribed the lowest dose possible to reduce the risk of intentional overdose.

Quetiapine fumarate should be used cautiously in older people and those with Alzheimer"s disease. Antipsychotic drug treatment has been associated with swallowing and breathing problems in these patients.

Animal studies suggest that Quetiapine fumarate may increase the risk of breast cancer, although human studies have not confirmed such a risk. If you have a history of breast cancer, see your doctor regularly for checkups.

If you are having problems with your vision, tell your doctor. There is a chance that Quetiapine fumarate may cause cataracts, and you may be asked to see an eye doctor when you start Quetiapine fumarate therapy, and every 6 months thereafter.

Quetiapine fumarate poses a very slight risk of seizures, especially if you are over 65, or have epilepsy or Alzheimer"s disease. The drug can also suppress an underactive thyroid, and generally causes a minor increase in cholesterol levels. There is also a remote chance that it will trigger a prolonged and painful erection.

Other antipsychotic medications have been known to interfere with the body"s temperature-regulating mechanism, causing patients to overheat. Although this problem has not occurred with Quetiapine fumarate, caution is still advisable. Avoid exposure to extreme heat, strenuous exercise, and dehydration.

Quetiapine fumarate is prescribed for the short-term treatment of rapid-onset bipolar mania; it is not approved for preventing future episodes. The effectiveness of the drug for treating mania for more than 3 weeks has not been studied.

The safety and effectiveness of Quetiapine fumarate have not been studied in children.

Possible food and drug interactions when taking Quetiapine fumarate

Quetiapine fumarate increases the effects of alcohol. Avoid alcoholic beverages while on Quetiapine fumarate therapy.

If Quetiapine fumarate is taken with certain other drugs, the effects of either could be increased, decreased, or altered. It is especially important to check with your doctor before combining Quetiapine fumarate with the following:

Barbiturates such as phenobarbital
Carbamazepine (Tegretol)
Cimetidine (Tagamet)
Erythromycin (Eryc, Ery-Tab)
Fluconazole (Diflucan)
Itraconazole (Sporanox)
Ketoconazole (Nizoral)
Levodopa (Laradopa, Sinemet)
Lorazepam (Ativan)
Phenytoin (Dilantin)
Rifampin (Rifadin, Rifamate, Rimactane)
Steroid medications such as hydrocortisone and prednisone
Thioridazine (Mellaril)

Special information if you are pregnant or breastfeeding

The possibility of harm to a developing baby has not been ruled out. You should take Quetiapine fumarate during pregnancy only if the benefits outweigh this potential risk. Notify your doctor as soon as you become pregnant or decide to become pregnant.

It is not known whether Quetiapine fumarate appears in breast milk, and breastfeeding is not recommended.

Recommended dosage

SCHIZOPHRENIA

Adults

The usual dosage range is 300 to 400 milligrams a day, divided into two or three smaller doses. Doses as low as 150 milligrams a day sometimes prove effective, and the dose rarely exceeds 750 milligrams per day. Doses above 800 milligrams per day have not been tested for safety. The dose is gradually increased over 4 days until the most effective dose is reached, using the following schedule: Day 1: Take 25 milligrams twice a day. Days 2, 3, and 4: The doctor will increase each daily dose by 25 to 50 milligrams, taken either two or three times a day. Day 5 and up: If needed, the doctor may increase each dose by 25 to 50 milligrams every 2 or more days.

BIPOLAR MANIA (SHORT-TERM TREATMENT OF ACUTE EPISODES)

Adults

The usual dosage range is 400 to 800 milligrams a day. Doses above 800 milligrams a day have not been tested for safety. The dosage will be gradually increased over 4 to 6 days until the most effective dose is reached, using the following schedule: Day 1: Take 50 milligrams twice a day. Day 2: The doctor will increase the dose to 100 milligrams twice a day. Day 3: The doctor will increase the dose to 150 milligrams twice a day. Day 4: The doctor will increase the dose to 200 milligrams twice a day. Days 5 and 6: If needed, the doctor may increase each dose by no more than 200-milligram increments to a total daily dose of 800 milligrams.

DOSAGE ADJUSTMENT

If you have liver problems, you may be started at 25 milligrams a day. The doctor will increase the dose as needed in increments of 25 to 50 milligrams a day based on your body"s response.

The dosage may also need to be lowered if you are weak, elderly, or prone to low blood pressure reactions. You may also need your dose adjusted if you"re taking certain drugs, including Dilantin, Tegretol, and phenobarbital.

Overdosage

Any medication taken in excess can have serious consequences. If you suspect an overdose, seek medical help immediately.

• Symptoms of Quetiapine fumarate overdose may include:
  Dizziness, drowsiness, fainting, rapid heartbeat