Quetiapine 

Overview

One of the second-generation antipsychotic drugs, often known as atypical antipsychotics, is Seroquel (quetiapine). (For a description of how these antipsychotics work, see the handout “Second-Generation Antipsychotics” Quetiapine differs from other medications in that it differs considerably from the more conventional, older antipsychotic drugs, such thioridazine, chlorpromazine, and Haldol (haloperidol). The Second-generation antipsychotics are less likely to cause adverse effects and have a broader range of action more so than the usual antipsychotics for movement problems. While traditional antipsychotics primarily act as dopamine-receptor antagonists, second-generation antipsychotics inhibit both serotonin and dopamine receptors.
When Quetiapine was originally made available for purchase in the US in 1997, medication could only be used to treat adult schizophrenia. Clinical research conducted in the following years revealed that Seroquel, like many other atypical antipsychotics, are useful in the treatment of bipolar disorder’s acute mania. The U.S. Food and Drug Administration FDA authorized Quetiapine for the treatment of depressive episodes, but not the XR version bipolar disorder-related acute mania. It is also authorized for the upkeep of bipolar disorder therapy.

prescription with divalproex (Depakote) or lithium, however Quetiapine has not received approval from the FDA for use in minors or teenagers. The term “labeled use” refers to the administration of a drug for its authorized uses. However, in actual practice, when published clinical studies, case reports, or their own are available, doctors often prescribe drugs for unapproved applications. The safety and effectiveness of certain medicines are supported by clinical experiences. Similar to various anti-second-generation Quetiapine may be used off-label to treat pediatric patients with psychotics as well as other psychiatric conditions.

Information about Dosing

Quetiapine is used at a beginning dose of 25–50 mg twice a day for schizophrenia. The amount administered is boosted by 25–50 mg every day or two until the desired dose of 300–400 mg double day is achieved. If necessary, the dose may be raised to a maximum of 800 mg per day after a few weeks. Quetiapine offers a broad dosage range. The range of effective doses for schizophrenia is 150–800 mg/day.
The suggested dosage for treating bipolar disorder-related depressive episodes is 50 mg at 100 mg at bedtime on the first day, 200 mg on the second, 300 mg on the third, and so on.
When treating acute mania in bipolar disorder, 100 mg/day is often started in two doses.
supplied dosages, and on the fourth day, the dosage has quickly raised to 400 mg/day. When necessary, the dose is 200 mg every day, up to a maximum of 800 mg per day on the seventh day. Quetiapine may be used either on its own or in conjunction with another mood stabilizer, such Depakote, until severe mania subsides. To determine the lowest dose necessary to sustain remission, dosage modifications can be necessary.
For elderly people or those with a medical problem, a more careful dose regimen is advised like hepatic illness. A lower beginning and finishing dose together with a gradual increase in dosage are recommended.

Typical Side Effects

Weakness and lightheadedness are two of Seroquel’s frequent adverse effects. It might be troublesome to remain sleepy throughout the day. Taking a lower dose in the morning and a bigger amount of the split dosage at bedtime may reduce drowsiness throughout the day. For instance, the patient would take 200 mg if the daily prescription was 300 mg, 100 mg at night and throughout the morning.

Extrapyramidal symptoms (EPS) are quite rare while using Seroquel. Neurological EPS
disruptions in the brain region responsible for controlling motor coordination brought on by antipsychotics (or other sources). Muscle stiffness, tremors, drooling, restlessness, and a “mask-like” facial expression are some of these adverse effects , a shuffling stride, and dystonia—muscle spasms that cause an irregular posture. EPS imitate Parkinson’s disease, and a large number of the symptoms and indicators are similar in both illnesses. Certain patients report akathisia, a self-described restless feeling that is followed by fidgeting and an inability to remain still when sitting or standing. Reducing the dose of the antipsychotic or taking an additional drug (anticholinergic) may help treat EPS in order to mitigate the adverse impact.

Quetiapine treatment often results in weight increase in patients. It seems that Quetiapine stimulates hunger and might cause some underlying metabolic alterations. The health of this weight increase is the main worry as repercussions for the patient, such as the possibility of diabetes and elevated cholesterol levels other fats, which might raise the chance of heart problems. Additionally, If they start to feel self-conscious about gaining too much weight, they should take their medicine. Should this adverse consequence be When anything goes wrong, individuals should talk to their doctor rather than stopping their prescription. Weight may frequently be controlled without taking Quetiapine with diet and exercise.

Quetiapine may prevent blood vessels from closing as a compensatory reaction to postural shift, which might cause a brief dip in blood pressure when the patient stands up too quickly. induce lightheadedness and dizziness. Orthostatic hypotension is the term for this response. Patients in particular, Elderly people and those on hypertension drugs should exercise caution and climb gradually to enable the body to adjust to prevent a sharp reduction in blood pressure by adjusting to the shift in posture.

Adverse Events and Safety Measures

Quetiapine may decrease mental and physical alertness, as well as produce sleepiness and sedation. Individuals should hold off on engaging in potentially risky tasks like operating equipment or driving a vehicle until they are certain that their capacity to do these jobs won’t be impacted by these adverse effects.

One possible side effect of antipsychotic treatment is tardive dyskinesia (TD). It is described as aberrant involuntary motions that develop slowly. Lip puckering, face grimacing, tongue darting and writhing, finger “pill-rolling,” and other abnormal motions are characteristic symptoms of TD, a possibly irreversible illness. It is thought that as therapy continues, the chance of TD rises. When the patient’s overall cumulative prescription quantity for antipsychotic drugs rises. The danger of TD compared to traditional antipsychotics, is much lower when it comes to second-generation antipsychotics.

An uncommon and severe response to antipsychotics is known as neuroleptic malignant syndrome (NMS). Severe muscular rigidity, raised body temperature, elevated heart rate and blood pressure, and irregular heartbeat are the symptoms as heartbeat and heavy perspiration. Coma and delirium may result from NMS. If medical assistance is not received, it may be deadly. There is no test to determine a person’s susceptibility to getting NMS in the presence of an antipsychotic. Because NMS is a medical emergency, it must be identified as soon as possible. demands being hospitalized, stopping the antipsychotic right away, and receiving urgent medical care.

Patients with brief, asymptomatic elevations in liver enzymes have been reported. However, it was determined that the higher enzyme levels were transient and not dangerous. However, patients’ liver Prior to starting Quetiapine therapy and again on occasion while on medication, function should be checked by laboratory testing.

Abnormalities in glucose control have been linked to the use of Quetiapine and other second-generation antipsychotic medications. Hyperglycemia, or elevated blood glucose levels, may be brought on by Quetiapine and sometimes result in diabetes mellitus. Although weight increase and glucose problems may sometimes be linked, both diseases can also occur in
patients who have not gained a lot of weight. Individuals who have gained considerable weight are more vulnerable to the adverse effects of medicine on cholesterol and blood sugar levels. A hyperglycemia warning is now mandated by the FDA and diabetes mellitus in their labeling, along with the usage of Quetiapine and other second-generation antipsychotics. individuals using Seroquel, particularly those with a history of diabetes in their family or a confirmed diagnosis, should be informed about this negative side effect and should periodically check their blood sugar levels while using Seroquel.

There is a higher chance of mortality among older dementia patients receiving treatment with second-generation antipsychotics, such as Seroquel. Data from clinical trials indicate that older people are more at risk compared to people receiving a placebo who did not get any medication for their dementia. Why these drugs are more likely to cause problems in this particular population is unknown. Although very low, the FDA mandates that Quetiapine include a warning about the potential risk in the package insert.

Seroquel’s labeling must include a warning about the possibility of suicide as part of its prescription for the treatment of depression. connected to drugs that treat depression. Short-term research revealed that antidepressants raised the risk of suicide thoughts and actions in kids and teenagers with severe depression and other mental health illnesses. Based on these results, the FDA mandates that the package insert include a warning that the prescriber recognize the potential for suicide in their patients who are beginning antidepressant medication, particularly in the case of younger individuals. The FDA’s studies indicate that the possibility of suicidal thoughts and actions linked to Age is a factor in antidepressant use. This is a phenomenon that most likely affects younger people.

to happen early on in the therapeutic regimen. Adults above the age of 24 did not seem to have any higher antidepressant risk of suicidality as compared to placebo. The results among patients older than 65 years indicated that the “protective effect” of antidepressants on suicide thoughts and actions. When beginning or discontinuing antidepressant medication, the patient especially if they are a kid or adolescent should be continuously monitored for worsening depressive symptoms.

Utilization during pregnancy and nursing: Category C

Seroquel’s safety during pregnancy has not been investigated in female subjects. The medication’s impact is Unknown to pregnant women who are growing a fetus. Studies on animals may reveal impacts on the growth of the fetus, however sufficient and well monitored human research are lacking. Human impacts are not typically predicted by research conducted on animals. As such, the use of Quetiapine in expectant mothers should always be considered in relation to the possible dangers. Women who are or may become pregnant should talk to their doctor about this. When women stop taking Seroquel, they could have a psychotic episode again. In these situations, the doctor could talk about the necessity to resume the medicine or look into getting a different prescription or course of therapy.

Quetiapine should not be used by nursing women since minute quantities may find their way into breast milk and be consumed by the unborn child. Breastfeeding should not begin if quitting the antipsychotic is not an option.

Potential Interactions with Drugs

When used with Seroquel, some drugs may have drug interactions that change their levels, which might cause unintended effects. The following provides an overview of potential medication interactions with Seroquel.  

• Alcohol consumption should be avoided by Quetiapine patients since the combination may impair thinking, judgment, and coordination. 
• Medicines that lower blood pressure Orthostatic hypotension may be more likely when Quetiapine is used with antihypertensive drugs such Inderal (propranolol) and Catapres (clonidine) and magnify its consequences. 
• Diflucan (fluconazole), itraconazole, and Nizoral (ketoconazole) , Antifungal medications may slow down Seroquel’s metabolism, raising blood levels and the risk of adverse consequences. 
• (carbamazepine) as well as (phenytoin), Tegretol and Dilantin may lower Quetiapine blood levels, which would reduce the medication’s ability to alleviate symptoms.
  of the disease. 
• Depressants of the central nervous system Drugs used for sedation, including barbiturates and benzodiazepines (such as Valium), opioid painkillers, and antihistamines, can increase sedation when combined with Seroquel.

Overdosing 

The most typical symptoms of a Quetiapine overdose include profound drowsiness, orthostatic hypotension, disorientation, and convulsions, a fast and erratic heart rate, and stiff muscles. The quantity consumed determines the result Particularly if Quetiapine was used in addition to other drugs.

Treating any suspected overdose as an emergency is imperative. The individual has to be brought to the emergency space for care and observation. It is advisable to bring the prescription bottle of medicine (as well as any additional medication that may have been taken in excess) since the information on the label may be useful in helping the treating physician figure out how many tablets the patient has taken.

Precaution Points to Remember

Quetiapine should never be stopped without first talking to your doctor.
• Take the missed dosage as soon as you remember that day. If the next scheduled dosage is approaching, skip the one you missed dosage and go on according to your usual dosing regimen. Avoid taking two doses at once. You may take Quetiapine with or without meals.
• Quetiapine may make you drowsy and sedentary, particularly when starting treatment. It may also make you attentive. When driving or doing other duties that call for attentiveness, proceed with care.
• Keep the medicine out of direct sunlight and dampness, in the light-resistant container that came with it. Warmth and Moisture may hasten the disintegration of your prescription and cause it to lose its medicinal benefits.
• Make sure kids can’t get to your medicine.