Can high doses of Seroquel (Quetiapine) cause hypotension even with chronic administration?

From the Guidelines

High doses of Seroquel (quetiapine) can cause hypotension even with chronic administration, particularly at doses above 300mg daily, due to its alpha-1 adrenergic blocking properties. According to the study published in the Annals of Oncology in 2018 1, quetiapine may cause orthostatic hypotension and dizziness, highlighting the need for caution when prescribing high doses. The study suggests that reducing the dose in older patients and those with hepatic impairment can help minimize these risks.

Key points to consider when prescribing high doses of quetiapine include:

• Monitoring for symptoms like dizziness, lightheadedness, or fainting, especially when standing up quickly
• Increased risk in elderly patients, those with cardiovascular conditions, or patients taking other medications that lower blood pressure
• Potential benefits of splitting the daily dose, taking it with food, or adjusting the timing to bedtime administration to manage side effects
• The importance of weighing the therapeutic benefits of quetiapine against the potential risks of hypotension, particularly in vulnerable patient populations.

As noted in the study 1, other second-generation antipsychotics like olanzapine may also cause orthostatic hypotension, emphasizing the need for careful consideration of the potential risks and benefits of these medications.

From the FDA Drug Label

Quetiapine may induce orthostatic hypotension associated with dizziness, tachycardia and, in some patients, syncope, especially during the initial dose-titration period, probably reflecting its α 1-adrenergic antagonist properties. Orthostatic hypotension, dizziness, and syncope may lead to falls Quetiapine should be used with particular caution in patients with known cardiovascular disease (history of myocardial infarction or ischemic heart disease, heart failure, or conduction abnormalities), cerebrovascular disease or conditions which would predispose patients to hypotension (dehydration, hypovolemia, and treatment with antihypertensive medications)

High doses of Seroquel (Quetiapine) can cause hypotension, even with chronic administration, due to its α 1-adrenergic antagonist properties.

• Key factors that increase the risk of hypotension include:
  • Known cardiovascular disease
  • Cerebrovascular disease
  • Conditions that predispose patients to hypotension, such as dehydration, hypovolemia, and treatment with antihypertensive medications
• Precautions should be taken to minimize the risk of orthostatic hypotension and syncope, including limiting the initial dose and monitoring patients closely, especially during the initial dose-titration period 2

From the Research

Hypotension and Seroquel (Quetiapine)

• High doses of Seroquel (Quetiapine) can cause hypotension, but the provided studies do not directly address this specific question.
• However, the studies suggest that certain antipsychotic and antidepressant medications can cause hypotension, particularly orthostatic hypotension, as a side effect 3, 4, 5, 6.
• Orthostatic hypotension is a common adverse effect of antipsychotics, and the risk is increased in patients with disorders of the autonomic nervous system, fluid imbalance, and those taking concomitant drug therapy that affects hemodynamic tone 3.
• The study on antidepressant drugs effects on blood pressure found that certain antidepressants, such as serotonin-norepinephrine reuptake inhibitors, can carry a greater risk of hypertension, but may also cause orthostatic hypotension, especially in patients with cardiovascular diseases 4.
• Another study found that venlafaxine, a serotonin-norepinephrine reuptake inhibitor, can be associated with adverse blood pressure effects, including orthostatic hypotension, in depressed older adults 5.
• A scoping review identified various drug classes, including neuroleptics, that can cause hypotension, highlighting the importance of healthcare professionals being aware of nonantihypertensive drugs that can cause hypotension 6.

Chronic Administration

• The studies do not provide direct evidence on the effects of chronic administration of high doses of Seroquel (Quetiapine) on hypotension.
• However, the study on antipsychotic pharmacotherapy and orthostatic hypotension suggests that prospective monitoring for changes in postural blood pressure is important, particularly in patients with psychotic disorders who may not articulate symptoms of orthostasis 3.
• The study on venlafaxine treatment in depressed older adults found that a large proportion of older adults treated with venlafaxine experience orthostatic hypotension, putting them at risk for falls, even with chronic administration 5.