Quiet 300 XR Tablet 10pcs

Uses of Quiet XR 300mg Tablet

• Schizophrenia
• Bipolar disorder
• Depression

How does Quiet XR 300mg Tablet work?

It acts by blocking certain receptors (dopamine (D2), serotonin 2A (5HT2A)) in the brain that cause abnormal mood changes and mental problems. As a result, it improves the positive and negative symptoms of schizophrenia and bipolar disorder.

Side Effects of Quiet XR 300mg Tablet

• Headache
• Dry Mouth
• Constipation
• Dizziness
• Sleepiness

Quick Suggestions:

• Regular monitoring and consultation with your doctor are essential to manage and adjust the treatment for the best results.
• Inform your doctor of any pre-existing conditions, other medications you are taking, and any side effects you experience.
• Follow your doctor’s instructions carefully regarding the dosage and duration of the medication.

Indications of Quiet XR 300mg Tablet

Quiet XR 300mg Tablet is used to manage bipolar disorder, schizophrenia, and depression (major depressive disorder). Bipolar disorder (also known as manic depression) is a mental disorder characterized by alternative episodes of mania (sudden unusual extreme sense of happiness) and depression.

Quetiapine Pharmacology and Mechanism of Action

Chemical Class:

• Quetiapine Fumarate is an atypical psychotropic agent that belongs to the chemical class known as dibenzothiazepine derivatives.

Receptor Antagonism:

• Quetiapine acts as an antagonist at multiple neurotransmitter receptors in the brain, including:
  • Serotonin Receptors: 5HT1A and 5HT2
  • Dopamine Receptors: D1 and D2
  • Histamine Receptors: H1
  • Adrenergic Receptors: α1 and α2

Lack of Affinity:

• Quetiapine has negligible affinity for cholinergic muscarinic and benzodiazepine receptors.

Proposed Mechanism of Action:

• The precise mechanism of action for quetiapine is not fully understood. However, its efficacy in treating schizophrenia and other psychoses is thought to be due to the combined antagonism of dopamine D2 and serotonin 5HT2 receptors.
  • Dopamine D2 Antagonism: May help reduce the positive symptoms of schizophrenia, such as hallucinations and delusions.
  • Serotonin 5HT2 Antagonism: May help alleviate negative symptoms and improve cognitive function.

Side Effects Explained by Receptor Antagonism:

• Somnolence: Likely due to antagonism of histamine H1 receptors.
• Orthostatic Hypotension: Attributed to antagonism of adrenergic α receptors.

Quetiapine Dosage Guidelines

Schizophrenia

Immediate Release:

• Day 1: 50 mg/day PO divided q12hr
• Days 2-3: Increase daily by 25-50 mg q8-12hr to 300-400 mg by Day 4
• Further Adjustments: Increments of 25-50 mg q12hr at intervals >2 days
• Dosage Range: 150-750 mg/day

Extended Release:

• Day 1: 300 mg/day PO
• Subsequent Increases: Up to 300 mg/day at intervals >1 day
• Maintenance (monotherapy): 400-800 mg/day
• Reinitiation:
  • If discontinued >1 week: Retitrate dose
  • If discontinued <1 week: Reinitiate at previous maintenance dose

Bipolar I Disorder (Mania)

Immediate Release (Monotherapy or Adjunct to Lithium/Divalproex):

• Day 1: 100 mg/day PO divided q12hr
• Day 2: 200 mg/day PO divided q12hr
• Day 3: 300 mg/day PO divided q12hr
• Day 4: 400 mg/day PO divided q12hr
• Further Adjustments: Up to 800 mg/day by Day 6 in increments <200 mg/day
• Dosage Range: 400-800 mg/day (max 800 mg/day)

Extended Release:

• Day 1: 300 mg PO once daily
• Day 2: 600 mg PO once daily
• Maintenance (Day 3 onward): 400-800 mg/day PO

Bipolar Disorder (Depressive Episodes)

Immediate Release or Extended Release:

• Day 1: 50 mg PO at bedtime
• Day 2: 100 mg PO at bedtime
• Day 3: 200 mg PO at bedtime
• Maintenance (Day 4 onward): 300 mg PO at bedtime

Bipolar I Disorder (Maintenance)

Immediate Release:

• Dosage Range: 400-800 mg/day PO divided q12hr

Extended Release:

• Dosage Range: 400-800 mg/day PO in a single dose

Major Depressive Disorder

Extended Release (Adjunct to Antidepressants):

• Days 1 and 2: 50 mg PO in the evening
• Day 3: May increase to 150 mg PO in the evening
• Dosage Range: 150-300 mg/day

Special Populations

Elderly:

• The slower rate of dose titration and lower daily therapeutic dose are recommended.

Hepatic Impairment:

• Initial dose: 25 mg daily
• Increase in increments of 25-50 mg daily until effective dose according to response and tolerability.

Pediatric Dose

Schizophrenia:

Immediate Release:

• Day 1: 50 mg/day PO divided q12hr
• Days 2-3: Increase daily by 25-50 mg q8-12hr to 300-400 mg by Day 4
• Further Adjustments: Increments of 25-50 mg q12hr at intervals >2 days
• Dosage Range: 150-750 mg/day

Extended Release:

• Day 1: 300 mg/day PO
• Subsequent Increases: Up to 300 mg/day at intervals >1 day
• Maintenance (monotherapy): 400-800 mg/day
• Reinitiation:
  • If discontinued >1 week: Retitrate dose
  • If discontinued <1 week: Reinitiate at previous maintenance dose

Bipolar I Disorder (Mania):

Immediate Release (Monotherapy or Adjunct to Lithium/Divalproex):

• Day 1: 100 mg/day PO divided q12hr
• Day 2: 200 mg/day PO divided q12hr
• Day 3: 300 mg/day PO divided q12hr
• Day 4: 400 mg/day PO divided q12hr
• Further Adjustments: Up to 800 mg/day by Day 6 in increments <200 mg/day
• Dosage Range: 400-800 mg/day (max 800 mg/day)

Extended Release:

• Day 1: 300 mg PO once daily
• Day 2: 600 mg PO once daily
• Maintenance (Day 3 onward): 400-800 mg/day PO

Bipolar Disorder (Depressive Episodes):

• Day 1: 50 mg PO at bedtime
• Day 2: 100 mg PO at bedtime
• Day 3: 200 mg PO at bedtime
• Maintenance (Day 4 onward): 300 mg PO at bedtime

Bipolar I Disorder (Maintenance):

Immediate Release:

• Dosage Range: 400-800 mg/day PO divided q12hr

Extended Release:

• Dosage Range: 400-800 mg/day PO in a single dose

Administration: This can be taken with or without food. It is advised to take it at the same time each day to maintain consistent medication levels in the body.

• Missed Dose: If you miss a dose, take it as soon as you remember. However, if it is close to the time of your next dose, skip the missed dose and resume your usual dosing schedule.
• Discontinuation: Do not stop taking Quiet XR 300 suddenly without consulting your doctor, as it may worsen your symptoms.

Drug Interactions and Precautions for Quetiapine

Increased Risk of Drowsiness and Postural Hypotension:

• Alcohol: Consuming alcohol while taking quetiapine can increase the risk of drowsiness and postural hypotension. It is advisable to avoid alcohol to prevent these effects.

Interaction with CYP3A4 Enzyme:

• CYP3A4 Inducers: Medications such as phenytoin and carbamazepine are known to induce the CYP3A4 enzyme. These inducers can decrease the plasma levels of quetiapine, potentially reducing its efficacy.
  • Phenytoin and Carbamazepine: May require dosage adjustments of quetiapine to maintain therapeutic levels.
• CYP3A4 Inhibitors: Medications such as ketoconazole and erythromycin inhibit the CYP3A4 enzyme. These inhibitors can increase the plasma levels of quetiapine, potentially increasing the risk of side effects.
  • Ketoconazole and Erythromycin: May necessitate a lower dose of quetiapine to avoid toxicity.

Recommendations

1. Avoid Alcohol: Patients should be advised to avoid alcohol while on quetiapine therapy due to the risk of increased drowsiness and postural hypotension.
2. Monitor Drug Interactions:
   • With CYP3A4 Inducers (e.g., Phenytoin, Carbamazepine): Regular monitoring of quetiapine levels and possibly increasing the dose of quetiapine.
   • With CYP3A4 Inhibitors (e.g., Ketoconazole, Erythromycin): Monitoring for signs of quetiapine toxicity and possibly reducing the dose of quetiapine.

Contraindications

Avoid taking Quetiapine if you are allergic to it. Seek immediate medical attention if you notice any symptoms such as skin rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, breathing difficulty, etc.

Pregnancy & Lactation

The safety and efficacy of Quetiapine during human pregnancy have not been established. Therefore, Quetiapine should only be used during pregnancy if the benefits justify the potential risks and the administered dose and duration of treatment should be as low and as short as possible. The degree to which Quetiapine is excreted into human milk is unknown. Women who are breast-feeding should therefore be advised to avoid breast-feeding while taking Quetiapine.

Precautions & Warnings

• Neuroleptic Malignant Syndrome (NMS): Discontinue immediately and seek medical help if you experience symptoms like fever, muscle rigidity, and altered consciousness or seizures.
• Orthostatic Hypotension: Initially, this medicine may cause a sudden drop in blood pressure when changing positions. Rise slowly if you have been sitting or lying down to prevent dizziness.
• Driving and Machinery: Causes dizziness and sleepiness; avoid driving or operating heavy machinery until you know how this medicine affects you.
• Weight Gain: May increase weight; adopt a healthy diet and exercise regularly to manage this side effect.
• Diabetes Risk: May increase the risk of developing diabetes; monitor blood glucose levels regularly.
• Mood Changes: Report any unusual changes in mood or behavior, new or worsening depression, or suicidal thoughts to your doctor.

Storage Conditions:

• Store in a cool, dry place away from light.
• Keep out of reach of children.
• Do not use it after the expiry date stated on the blister pack and carton. The expiry date refers to the last day of that month.