Quetiapine (Seroquel)

 

HALF-LIFE: Quetiapine 6-7 hours; Norquetiapine (active metabolite)
STARTING DOSE: IR: 25mg-50mg PO BID; XR: 300mg PO QHS
TARGET DOSING RANGE: 50mg-800mg daily
BEST TIME TO DOSE: Bedtime
HOW TO DOSE:
>> IR: Initial 25mg-50mg PO BID. Increase by 50mg-100mg per day
every 1-4 days.
>> XR: Initial 150mg-300mg PO QHS. Increase by 150mg-300mg per day every 2-7 days.
>> Max dose 800mg/day (some patients may require doses of up to 1200mg/day)
PREGNANCY: Minimal data on safety.
BREASTFEEDING: Minimal data on safety.

 

 

FDA INDICATIONS:
1) Schizophrenia, 13yo and older
2) Bipolar disorder (manic/mixed), 10yo and older
3) Bipolar depression
4) Adjunctive treatment in Unipolar Major Depression

 

 

Additional Information

Norquetiapine is the active metabolite of quetiapine and has antagonist effects at NET (norepinephrine transporter), 5HT7, 5HT2C, and α2 receptors as well as partial agonist effects at 5HT1A receptors

Quetiapine is a different drug at different doses

Hypnotic dose: 50mg

Antidepressant dose: 300mg

Antipsychotic dose: 800mg

Very Low risk for extrapyramidal side effects (EPS)

Very low risk for prolactin elevation

Weak D2 antagonism makes quetiapine a preferred antipsychotic for Parkinson’s (although pimavanserin is a better option)

Weight Gain is common

Sedation is common

Orthostatic hypotension is common

Intermediate-high cardio-metabolic risk (↑triglycerides, insulin resistance)

References:

  1. Cooper, J. R., Bloom, F. E., & Roth, R. H. (2003). The biochemical basis of neuropharmacology (8th ed.). New York, NY, US: Oxford University Press.
  2. Iversen, L. L., Iversen, S. D., Bloom, F. E., & Roth, R. H. (2009). Introduction to neuropsychopharmacology. Oxford: Oxford University Press.
  3. Puzantian, T., & Carlat, D. J. (2016). Medication fact book: for psychiatric practice. Newburyport, MA: Carlat Publishing, LLC.
  4. J. Ferrando, J. L. Levenson, & J. A. Owen (Eds.), Clinical manual of psychopharmacology in the medically ill(pp. 3-38). Arlington, VA, US: American Psychiatric Publishing, Inc.
  5. Schatzberg, A. F., & DeBattista, C. (2015). Manual of clinical psychopharmacology. Washington, DC: American Psychiatric Publishing.
  6. Schatzberg, A. F., & Nemeroff, C. B. (2017). The American Psychiatric Association Publishing textbook of psychopharmacology. Arlington, VA: American Psychiatric Association Publishing.
  7. Stahl, S. M. (2014). Stahl’s essential psychopharmacology: Prescriber’s guide (5th ed.). New York, NY, US: Cambridge University Press.
  8. Stahl, S. M. (2013). Stahl’s essential psychopharmacology: Neuroscientific basis and practical applications (4th ed.). New York, NY, US: Cambridge University Press.
  9. Whalen, K., Finkel, R., & Panavelil, T. A. (2015). Lippincotts illustrated reviews: pharmacology. Philadelphia, PA: Wolters Kluwer.