Quetiapine 400mg ER Tablets

Quetiapine is an atypical antipsychotic with a broad receptor binding profile. It exhibits antagonism at serotonin 5-HT2A and dopamine D2 receptors, which is thought to mediate its antipsychotic effects. It also has high affinity for histamine H1 and alpha1-adrenergic receptors, contributing to side effects like sedation and orthostatic hypotension. It has moderate affinity for alpha2-adrenergic receptors and muscarinic M1 receptors. The active metabolite, norquetiapine (N-desalkylquetiapine), has high affinity for the norepinephrine transporter (NET) and partial agonist activity at the 5-HT1A receptor, which may contribute to its antidepressant effects.

Urgent Side Effects: Seek Medical Help Right Away

Although rare, some people may experience severe and potentially life-threatening side effects while taking this medication. If you notice any of the following symptoms, contact your doctor or seek immediate medical attention:

Signs of an allergic reaction, such as:
+ Rash
+ Hives
+ Itching
+ Red, swollen, blistered, or peeling skin (with or without fever)
+ Wheezing
+ Tightness in the chest or throat
+ Difficulty breathing, swallowing, or talking
+ Unusual hoarseness
+ Swelling of the mouth, face, lips, tongue, or throat
Signs of low thyroid levels, including:
+ Constipation
+ Sensitivity to cold
+ Memory problems
+ Mood changes
+ Burning, numbness, or tingling sensations
Severe dizziness or fainting
Chest pain or pressure, rapid heartbeat, or irregular heartbeat
Difficulty controlling body movements, twitching, balance problems, or trouble swallowing or speaking
Shakiness, difficulty moving around, or stiffness
Drooling
Seizures
Changes in vision
Severe constipation or stomach pain (may indicate a serious bowel problem)
Difficulty urinating
Flu-like symptoms
Enlarged breasts, nipple discharge, erectile dysfunction, or menstrual changes
Tardive dyskinesia, a severe muscle problem that may cause involuntary movements (more common in people with diabetes, older adults, especially older females, and those taking higher doses or using the medication for an extended period)

If you experience any of the following symptoms, contact your doctor right away:
Trouble controlling body movements
Problems with your tongue, face, mouth, or jaw, such as:
+ Tongue sticking out
+ Puffing cheeks
+ Mouth puckering
+ Chewing movements

Other Possible Side Effects

Like all medications, this drug can cause side effects. While many people may not experience any side effects or only minor ones, it's essential to discuss any concerns with your doctor. If you experience any of the following side effects, contact your doctor or seek medical help if they bother you or persist:

Dizziness, drowsiness, fatigue, or weakness
Headache
Nervousness or excitability
Difficulty sleeping
Constipation
Dry mouth
Increased appetite
Weight gain
Upset stomach or vomiting
Stomach pain
Back pain
Stuffy nose

This is not an exhaustive list of possible side effects. If you have questions or concerns, contact your doctor. You can also report side effects to the FDA at 1-800-332-1088 or online at https://www.fda.gov/medwatch.

Before Taking This Medication: Important Information to Share with Your Doctor

It is essential to inform your doctor about the following:

Any allergies you have, including allergies to this medication, its components, or other substances, such as foods or drugs. Be sure to describe the allergic reaction you experienced, including any symptoms that occurred.
Certain health conditions, including:
+ Low levels of potassium or magnesium in your blood.
+ A history of abnormal heart rhythms, such as a prolonged QT interval on an electrocardiogram (ECG).
If you are taking any medications that can cause abnormal heart rhythms, specifically those that can prolong the QT interval. There are many drugs that can have this effect, so it is crucial to ask your doctor or pharmacist if you are unsure.

This list is not exhaustive, and it is vital to discuss all your medications and health conditions with your doctor. Please provide your doctor and pharmacist with a comprehensive list of:

All prescription and over-the-counter (OTC) medications you are taking.
Any natural products or vitamins you are using.
All your health problems, including any medical conditions or allergies.

Before starting, stopping, or changing the dose of any medication, including this one, you must consult with your doctor to ensure your safety. It is crucial to verify that it is safe to take this medication with all your other medications and health conditions.

Important Warnings and Cautions for Patients Taking This Medication

Informing Your Healthcare Providers
It is essential to inform all your healthcare providers, including doctors, nurses, pharmacists, and dentists, that you are taking this medication.

Caution with Daily Activities
Avoid driving and engaging in activities that require alertness until you understand how this medication affects you. To minimize the risk of dizziness or fainting, rise slowly from a sitting or lying down position, and exercise caution when climbing stairs.

Potential Side Effects
Rarely, cataracts may occur. Additionally, this medication may increase the risk of developing high blood sugar, diabetes, high cholesterol, and weight gain, which can contribute to heart and brain blood vessel disease.

Monitoring for High Blood Sugar
If you experience symptoms of high blood sugar, such as confusion, drowsiness, unusual thirst or hunger, frequent urination, flushing, rapid breathing, or fruity-smelling breath, notify your doctor promptly.

Risk of Infection
Low white blood cell counts have been associated with this medication, increasing the risk of infection. In rare cases, these infections can be fatal. Inform your doctor if you have a history of low white blood cell count, and seek immediate medical attention if you experience symptoms of infection, such as fever, chills, or sore throat.

Neuroleptic Malignant Syndrome (NMS)
A rare but potentially life-threatening condition called NMS may occur. Seek immediate medical attention if you experience symptoms such as fever, muscle stiffness, dizziness, severe headache, confusion, altered thinking, rapid heartbeat, irregular heartbeat, or excessive sweating.

Dizziness and Falling
This medication may cause dizziness, drowsiness, and impaired balance, increasing the risk of falls and related injuries, such as fractures.

Constipation and Bowel Blockage
Constipation is a common side effect of this medication. In rare cases, bowel blockage may occur, which can be fatal, especially when combined with other medications that slow gastrointestinal movement. If you have concerns, discuss them with your doctor.

Special Considerations for Older Adults
If you are 65 or older, use this medication with caution, as you may be more susceptible to side effects. Additionally, older adults with dementia who take this medication have an increased risk of stroke, which can be fatal. This medication is not approved for treating dementia-related mental health issues.

Pregnancy and Breastfeeding
This medication may affect fertility, but this effect is reversible when the medication is discontinued. If you are pregnant, plan to become pregnant, or are breastfeeding, discuss the benefits and risks with your doctor. Taking this medication during the third trimester of pregnancy may cause side effects or withdrawal symptoms in the newborn.

Pediatric Use
If the patient is a child, use this medication with caution, as the risk of certain side effects may be higher in children. High blood pressure has been reported in children and teenagers taking this medication; therefore, regular blood pressure monitoring is essential, as advised by your child's doctor.

• Strong CYP3A4 inhibitors (e.g., ketoconazole, itraconazole, clarithromycin, erythromycin, protease inhibitors like ritonavir, indinavir, nelfinavir, saquinavir)

• CYP3A4 inducers (e.g., carbamazepine, phenytoin, rifampin, barbiturates, St. John's Wort) - may significantly decrease quetiapine levels, requiring dose adjustment or alternative therapy.
• CNS depressants (e.g., alcohol, benzodiazepines, opioids, sedating antihistamines) - additive CNS depressant effects.
• Drugs that prolong QT interval (e.g., Class IA and III antiarrhythmics, some antipsychotics, moxifloxacin) - theoretical risk of additive QT prolongation, though quetiapine itself has minimal effect.
• Antihypertensives - enhanced hypotensive effects due to alpha1-adrenergic antagonism.

• Dopaminergic agonists (e.g., levodopa, bromocriptine) - quetiapine may antagonize their effects.
• Anticholinergic drugs - potential for additive anticholinergic side effects (e.g., constipation, dry mouth, urinary retention).

• Not available

• Sedation/Drowsiness
• Dizziness/Orthostatic Hypotension
• Dry mouth
• Constipation
• Tachycardia
• Weight gain
• Blurred vision
• Urinary retention
• Akathisia (restlessness)
• Dystonia (muscle spasms)
• Parkinsonism (tremor, rigidity)
• Tardive dyskinesia (involuntary movements)
• Signs of hyperglycemia (polyuria, polydipsia, polyphagia)
• Signs of neuroleptic malignant syndrome (fever, muscle rigidity, altered mental status, autonomic instability)
• Suicidal thoughts or behaviors (especially in young adults and adolescents)

Category C. Use during pregnancy only if the potential benefit justifies the potential risk to the fetus. Neonates exposed to antipsychotic drugs during the third trimester of pregnancy are at risk for extrapyramidal and/or withdrawal symptoms following delivery.

Quetiapine is excreted into human milk. The decision to breastfeed should consider the developmental and health benefits of breastfeeding, the mother’s clinical need for quetiapine, and any potential adverse effects on the breastfed infant from the drug or from the underlying maternal condition. Monitor infants for sedation, irritability, poor feeding, and developmental milestones.

Not approved for use in pediatric patients under 10 years of age for any indication. For adolescents (10-17 years) with bipolar mania and adolescents (13-17 years) with schizophrenia, specific dosing guidelines apply. Not established for bipolar depression or adjunctive MDD in pediatric patients. Increased risk of suicidal thoughts and behaviors in children, adolescents, and young adults.

Increased risk of mortality in elderly patients with dementia-related psychosis (Black Box Warning). Increased risk of orthostatic hypotension, sedation, and falls. Lower starting doses and slower titration are recommended. Monitor closely for adverse effects.

• Quetiapine ER should be taken once daily, preferably in the evening, without food or with a light meal (e.g., 300 calories).
• Orthostatic hypotension is a common side effect, especially during initial titration. Advise patients to rise slowly.
• Significant weight gain and metabolic changes (hyperglycemia, dyslipidemia) are common. Regular monitoring of weight, glucose, and lipids is crucial.
• Sedation is a prominent side effect, often utilized for sleep induction in patients with insomnia associated with their psychiatric condition.
• Do not crush, chew, or break the extended-release tablets, as this will alter drug release and may lead to rapid absorption and increased side effects.
• Patients should be monitored for suicidal ideation, especially at the beginning of treatment and with dose changes, particularly in younger populations.
• Consider the active metabolite, norquetiapine, which has antidepressant properties and may contribute to the efficacy in bipolar depression and adjunctive MDD.

• Other atypical antipsychotics (e.g., Olanzapine, Risperidone, Aripiprazole, Ziprasidone, Lurasidone, Cariprazine, Brexpiprazole)
• Mood stabilizers (e.g., Lithium, Valproate, Lamotrigine) for bipolar disorder
• Antidepressants (e.g., SSRIs, SNRIs) for major depressive disorder (as monotherapy or in combination with other agents)
• ECT (Electroconvulsive Therapy) for severe or treatment-resistant conditions

If your symptoms or health issues persist or worsen, it is essential to contact your doctor promptly. To ensure safe use, never share your medication with others or take someone else's medication. This medication is accompanied by a Medication Guide, which provides crucial information for patients. Please read this guide carefully and review it again whenever you receive a refill of this medication. If you have any questions or concerns about this medication, consult your doctor, pharmacist, or other healthcare provider. In the event of a suspected overdose, immediately call your local poison control center or seek emergency medical attention. When reporting the incident, be prepared to provide details about the medication taken, the amount, and the time it occurred.