Quetiapine

Aka: Quetiapine, Seroquel

advertisement

II. Class

  1. Atypical Antipsychotic (Second Generation Antipsychotic)
  2. Neuroleptic
  3. Dibenzothiazepine Antipsychotic

III. Mechanism

  1. Stronger Antagonist at Serotonin 5HT2 receptors than Dopamine D2 receptors
  2. Potent alpha-1 Adrenergic ReceptorAntagonist (risk of Hypotension)
  3. Weak Antagonist at Dopamine (D2), Histamine muscarinic (M1) and Serotonin (5HT-1A) with risk of sedation

IV. Indications

  1. Schizophrenia
  2. Psychosis in Dementia
  3. Bipolar Disorder
  4. Mania
  5. Major Depression (adjunct)
  6. Autism (not FDA approved)
  7. Insomnia (not FDA approved)
  8. Obsessive Compulsive Disorder (not FDA approved)
  9. Generalized Anxiety Disorder (not FDA approved)

V. Precautions

  1. Use lower doses and slower titration in the elderly and liver dysfunction
    1. Start at 25 mg/day and increase by no more than 25 to 50 mg/day
  2. Restart dose titration if Quetiapine was stopped for more than 7 days
  3. Low risk of Tardive Dyskinesia and Extrapyramidal Side Effects

VI. Dosing: Schizophrenia

  1. Adults (or Children age 13 to 17 years) Regular Immediate Release Oral Tablets
    1. Initial: 25 mg orally twice daily
    2. Increase in 25-50 mg/day increments divided 2-3 times daily
    3. Example of a more rapid titration
      1. Day 1: Take 25 mg orally twice daily
      2. Day 2: Take 50 mg orally twice daily
      3. Day 3: Take 100 mg orally twice daily
      4. Day 4: Take 150 mg orally twice daily
      5. Day 5: Take 200 mg orally twice daily
    4. Target: 300-400 mg/day orally divided twice to three times daily
    5. Maximum dose: 800 mg/day
  2. Adults (or Children age 13 to 17 years) Sustained Release Tablets (Seroquel XR)
    1. Avoid taking Sustained Release Tablets with food
    2. May start at up to 300 mg orally each evening at bedtime
      1. May increase up to 300 mg/day
    3. Example of dose titration
      1. Dose 1: Take 50 mg orally at bedtime
      2. Dose 2: Take 100 mg orally at bedtime
      3. Dose 3: Take 200 mg orally at bedtime
      4. Dose 4: Take 300 mg orally at bedtime
      5. Dose 5: Take 400 mg orally at bedtime
    4. Target 400 to 800 mg/day
    5. Maximum 800 mg/day

VII. Dosing: Acute Bipolar Mania or Mixed Disorder

  1. Adults Regular (or Children age 13 to 17 years) Immediate Release Oral Tablets
    1. Day 1: Start 50 mg orally twice daily
    2. Day 2: Take 100 mg orally twice daily
    3. Day 3: Take 150 mg orally twice daily
    4. Day 4: Take 200 mg orally twice daily
    5. Day 5: Take 300 mg orally twice daily
    6. Day 6: Take 400 mg orally twice daily
    7. Target: 400 to 600 mg/day (up to 800 mg/day in adults)
    8. Maximum: 600 mg/day (up to 800 mg/day in adults)
  2. Adults (or Children age 13 to 17 years) Extended Release Oral Tablets (Seroquel XR)
    1. Avoid taking Sustained Release Tablets with food
    2. May consider rapid start higher dosing in adults (or use titrating dose below)
      1. Day 1: 300 mg orally at bedtime
      2. Day 2: 600 mg orally daily bedtime
    3. Titrate to dose in children age 13 to 17 years
      1. Day 1: Start 50 mg orally at bedtime
      2. Day 2: Take 100 mg orally at bedtime
      3. Day 3: Take 200 mg orally at bedtime
      4. Day 4: Take 300 mg orally at bedtime
      5. Day 5: Take 400 mg orally at bedtime
    4. Target: 400 to 600 mg orally daily each evening (up to 800 mg/day in adults)
    5. Maximum: 600 mg/day (up to 800 mg/day in adults)

VIII. Dosing: Bipolar Depression or Major Depression

  1. Adults Extended Release Oral Tablets (Seroquel XR)
    1. Titrate rapidly as below in Bipolar Depression (more gradually in Major Depression)
    2. Day 1: Start 50 mg orally at bedtime
    3. Day 2: Take 100 mg orally at bedtime
    4. Day 3: Take 200 mg orally at bedtime
    5. Day 4: Take 300 mg orally at bedtime
    6. Continue 300 mg orally daily at bedtime
    7. Maximum: 30 mg/day

IX. Dosing: Miscellaneous

  1. Adults with Refractory Insomnia (not FDA approved)
    1. Start 50 mg orally at bedtime
    2. Titrate as needed to effect
    3. Maximum: 400 mg
  2. Elderly Regular Oral Tablets
    1. Initial dose: 12.5 mg orally at bedtime
    2. Titrate dose every few days (caution due to sedation)

X. Pharmacokinetics: Quetiapine Regular Tablets

  1. Use lower doses and slower titration in the elderly and liver dysfunction
  2. Lipophilic
  3. Large volume of distribution (10 L/kg +/-4 L/kg)
  4. Plasma Protein binding: 83%
  5. Not dialyzable
  6. Half-Life: 6 hours
  7. Peak Levels: 2-3 hours
  8. Metabolism: CYP 3A4

XI. Adverse Effects: General

  1. Sedation
  2. Headache
  3. Orthostatic Hypotension
  4. Cataract formation
  5. Dry Mouth (although Anticholinergic effects are minimal with Quetiapine)
  6. Weight gain
  7. Hyperglycemia and increased risk of Diabetes Mellitus
  8. Neuroleptic Malignant Syndrome
  9. QTc Prolongation

XII. Adverse Effects: Overdose

  1. See Quetiapine Overdose
  2. Somnolence
  3. Tachycardia
  4. Hypotension

XIII. Drug Interactions

  1. Metabolized by CYP3A4
    1. Decrease dose to one-sixth of typical dose when on strong CYP3A4 inhibitors
    2. Increase dose (as much as 5 fold) when on stong CYP3A4 inducers
  2. Increase Antipsychotic levels (toxicity risk): Monitor for toxicity
    1. Clarithromycin
    2. Erythromycin
    3. Grapefruit juice
    4. Fluconazole
    5. Itraconazole
    6. Ketoconazole
    7. Quinidine
  3. Decrease Antipsychotic levels (lower efficacy)
    1. Barbiturates
    2. Carbamazepine
    3. Phenytoin
    4. Rifampin
    5. Theophylline
  4. Other effects
    1. Avoid concurrent use of other medications prolonging QT Interval
      1. See Prolonged QT Interval due to Medication

XIV. Safety

  1. Pregnancy Category C
  2. Avoid in Lactation

XV. Monitoring

  1. See Quetiapine Overdose
  2. See Antipsychotic
  3. Screen for Cataract formation every 6 months
  4. Consider EKG, Electrolyte and Magnesium monitoring due to QT Interval prolongation risk
  5. Monitor weight, Fasting Glucose and Serum Triglycerides (at baseline and periodically)

XVI. Resources

  1. Quetiapine (DailyMed)
    1. https://dailymed.nlm.nih.gov/dailymed/lookup.cfm?setid=6b7d7d2f-a50b-8e21-2de4-ccc102016384

XVII. References

  1. (2016) Med Lett Drugs Ther 58(1510): 160-5
  2. Olson (2020) Clinical Pharmacology, Medmaster Miami, p. 42-3
  3. Otter and Tomaszewski (2018) Crit Dec Emerg Med 32(8): 32
  4. Hamilton (2020) Tarascon Pocket Pharmacopoeia

Images: Related links to external sites (from Bing)

These images are a random sampling from a Bing search on the term "Quetiapine." Click on the image (or right click) to open the source website in a new browser window. Search Bing for all related images

Related Studies

Cost: Medications

quetiapine (on 12/21/2022 at Medicaid.Gov Survey of pharmacy drug pricing)
QUETIAPINE 150 MG TABLET Generic $1.17 each
QUETIAPINE ER 150 MG TABLET Generic $0.27 each
QUETIAPINE ER 200 MG TABLET Generic $0.32 each
QUETIAPINE ER 300 MG TABLET Generic $0.36 each
QUETIAPINE ER 400 MG TABLET Generic $0.41 each
QUETIAPINE ER 50 MG TABLET Generic $0.17 each
QUETIAPINE FUMARATE 100 MG TAB Generic $0.05 each
QUETIAPINE FUMARATE 200 MG TAB Generic $0.11 each
QUETIAPINE FUMARATE 25 MG TAB Generic $0.03 each
QUETIAPINE FUMARATE 300 MG TAB Generic $0.14 each
QUETIAPINE FUMARATE 400 MG TAB Generic $0.18 each
QUETIAPINE FUMARATE 50 MG TAB Generic $0.05 each
FPNotebook does not benefit financially from showing this medication data or their pharmacy links. This information is provided only to help medical providers and their patients see relative costs. Insurance plans negotiate lower medication prices with suppliers. Prices shown here are out of pocket, non-negotiated rates. See Needy Meds for financial assistance information. GoodRx is another tool for finding lower drug prices.

Related Topics in Pharmacology

advertisement