What are Benzodiazepines?
Benzodiazepines are a class of psychoactive drugs known for their depressant effect on the central nervous system (CNS) [1]. They have been in clinical use since the 1960s and are among the most widely prescribed drug classes in the United States [1, 2]. Examples of benzodiazepines are the generic name alprazolam drug or diazepam, sold under multiple brand names including Valium.
Benzodiazepines work by enhancing the activity of GABA, an inhibitory neurotransmitter. This slows neurotransmission and produces sedative and anxiolytic effects [2]. They act through allosteric modulation of the GABA-A receptor, a chloride ion channel, their common and predominant mechanism of action [3]. This means they bind to a side pocket of the receptor, changing the way it sense natural GABA released within your body.
Uses of benzodiazepines
These drugs are used for a broad range of conditions, including anxiety and obsessive-compulsive disorders, phobias, sleep-related problems associated with insomnia, and for the management of alcohol and GHB withdrawal [4]. They are also used for those struggling with sleep, anxiety, spasticity due to CNS pathology, muscle relaxation, and epilepsy [1].
Benzodiazepine risks and side effects
However, despite their usefulness, benzodiazepines present a potential for substance abuse disorders relating to benzodiazepines and dependence [4]. Their regular use has been shown to cause severe, harmful psychological and physical dependence, leading to withdrawal symptoms similar to that of alcohol withdrawal [1]. Other potential side effects include low blood pressure due to sedative properties on the cardiovascular system
What is Trazodone?
Trazodone is a prescription drug in the class of antidepressants, meaning it is primarily used to treat major depressive disorder in adults [5]. Trazodone has a unique pharmacological profile, differing from other antidepressants, such as tricyclic or monoamine oxidase inhibitor antidepressants (MAO inhibitor) , and is considered to represent a new class of antidepressant drugs [6]. It is also different to serotonin reuptake inhibitors (SRIs) or selective serotonin reuptake inhibitors (SSRIs), as it is also a serotonin agonist.
The exact mechanism of how trazodone works has yet to be fully understood, but it is believed to increase serotonin levels in the brain. Serotonin is a chemical in the brain that helps stabilize mood and is often abbreviated to 5-HT [5]. Trazodone blocks the postsynaptic serotonin receptors, 5-HT(2A), and 5-HT(2C) and weakly inhibits presynaptic 5-HT transporters [7].
What is trazodone used for?
In addition to its antidepressant effects, trazodone has been found to have anxiolytic and hypnotic activity. This makes it helpful for treating conditions beyond depression, such as anxiety disorders, panic disorders, insomnia, and chronic pain [8]. It can also be used for post traumatic stress disorder in patients who do not respond to the first line therapy or cognitive behavioral therapy. The maximum dose of trazodone is 600mg a day in inpatient settings, but a lower dose is given in outpatient settings that is well tolerated over long-term use [9].
It's important to know that while trazodone is FDA-approved for the treatment of depression, its use for other conditions is considered off-label in the United States [10].
Trazodone risks and side effects
Adverse effects of trazodone include a risk for serotonin syndrome, a condition where your body has too much serotonin. It has potential interactions with cardiovascular medications and common side effects include heart palpitations, suicidal thoughts or hallucinations. These negative side effects usually subside after stopping trazodone [9].
Is Trazodone a Benzodiazepine?
Trazodone is not a benzodiazepine.
Trazodone is a unique antidepressant that belongs to the class of serotonin receptor antagonists and reuptake inhibitors [11]. This means it mimics the activity of serotonin and activates serotonin receptors, and blocks reuptake receptors, which facilitates its antidepressant effects. In contrast, benzodiazepines mimic the activity of the GABA neurotransmitter, an inhibitory neurotransmitter. This means it binds to GABA receptors. The role of serotonin in the brain is much more complex, as it modulates the activity of neurons dependent on the spectrum of receptors it acts on. This means that trazodone is chemically distinct from benzodiazepines and has different pharmacological targets [12].
Trazodone and benzodiazepines for anxiety
Despite their distinct pharmacology, there is an overlap in the uses of trazodone and benzodiazepines. It has been shown that trazodone can be used for some of the anxiolytic purposes benzodiazepines are used for [13]. Thanks to the complex properties of serotonin in the brain, trazodone can also reduce anxiety, which is what benzodiazepines do, and promote sedation and treat sleep disorders. This property is particularly useful in benzodiazepine-dependent patients - that is, patients who are addicted or tolerant to the effects of benzodiazepines. In contrast to benzodiazepines, trazodone use is non-addictive, meaning it is a safe and potentially long-term alternative for this patient group [12].
Summary: Is Trazodone a Benzodiazepine?
To summarise, trazodone is an antidepressant and is not a benzodiazepine. However, trazodone can have anxiolytic and sedative properties similar to benzodiazepines, albeit with a lower risk of becoming dependent on the drug. Therefore, your healthcare provider may prescribe trazodone for you for anxiety or insomnia, demonstrating comparable mental health benefits.
Caution
Trazodone and benzodiazepine drugs in general are prescription drugs and must not be taken outside of medical supervision. Always consult a medical professional when starting a new medication to avoid unwanted drug interactions.