What are the cardiac risks associated with Ativan (lorazepam) use?

From the Guidelines

Ativan (lorazepam) does not have a significant direct effect on prolonging the QTc interval, but its use requires caution due to potential indirect cardiac risks. The primary concerns with Ativan are related to its potential to cause respiratory depression, especially when combined with other central nervous system depressants, which can indirectly affect cardiac function through hypoxemia 1.

Key Considerations

• Ativan can cause mild hypotension and bradycardia, particularly in elderly patients or those with pre-existing cardiovascular conditions, when administered intravenously or at higher doses.
• The medication may potentiate the cardiac depressant effects of other medications, such as opioids, alcohol, or other central nervous system depressants.
• Long-term use of Ativan can lead to physiological dependence, and abrupt discontinuation could trigger autonomic nervous system instability, affecting heart rate and blood pressure.
• Patients with severe pulmonary disease or sleep apnea should use Ativan cautiously due to the risk of respiratory depression and subsequent indirect cardiac effects.

Clinical Implications

The use of Ativan should be carefully considered, especially in patients with pre-existing cardiac conditions or those taking other medications that could potentiate its effects. Monitoring is crucial to minimize the risk of adverse cardiac events. According to the available evidence, the primary focus should be on the cautious use of Ativan, especially in vulnerable populations, rather than a direct concern about QTc interval prolongation 1.

Management and Monitoring

• Patients should be started on the lowest effective dose, and regular monitoring of their cardiac and respiratory status is recommended, especially in high-risk populations.
• The combination of Ativan with other central nervous system depressants should be avoided whenever possible to minimize the risk of respiratory depression and subsequent cardiac complications.
• For patients requiring long-term use of Ativan, gradual tapering should be considered when discontinuing the medication to prevent withdrawal symptoms that could affect cardiac stability.

From the Research

Cardiac Risks Associated with Ativan (Lorazepam) Use

• Ativan (lorazepam) is a benzodiazepine used to treat anxiety disorders, insomnia, and seizures.
• The cardiac risks associated with Ativan use are not well-established, but studies suggest that benzodiazepines may not significantly prolong the QT interval 2.
• A study found that intramuscular lorazepam did not significantly prolong the QT interval in patients with schizophrenia, with effects nullified by correction for heart rate elevation 2.

QT Interval Prolongation and Ativan

• QT interval prolongation is a potential risk factor for Torsades de Pointes (TdP), a life-threatening cardiac arrhythmia 3, 4.
• However, studies have not found a significant association between Ativan use and QT interval prolongation 2.
• Other factors, such as hypokalemia, use of diuretics, and antiarrhythmic drugs, are known to increase the risk of QT interval prolongation 4.

Polytherapy and QT Interval Prolongation

• Combining Ativan with other psychotropic drugs, such as antidepressants, may increase the risk of QT interval prolongation 5.
• A study found that combination therapy with an antipsychotic and an antidepressant significantly prolonged the QT interval, while monotherapy with an antipsychotic did not 5.
• Another study found that antidepressants, including selective serotonin reuptake inhibitors and venlafaxine, may increase the risk of QT interval prolongation 6.