Anxiety disorders are common in Americans, affecting more than one in four adults at some point in their lives. Treatment typically consists of a combination of pharmacotherapy and cognitive behavioral therapy. Neurotransmitters like serotonin, norepinephrine, and gamma-aminobutyric acid (GABA) are involved in the pathophysiology of anxiety disorders, so drugs that target these neurotransmitters are often used to help control symptoms. These neurotransmitters facilitate communication between nerve cells in the brain. When that communication is disrupted, symptoms of depression, anxiety, and other disorders can develop.
PET scans have demonstrated a reduction in serotonin receptor binding in patients with anxiety disorder. Selective serotonin reuptake inhibitors (SSRIs), a class of antidepressants that includes fluoxetine, citalopram, and sertraline work by increasing the availability of serotonin in the space between nerve cells (synapse) and allow for improved communication between cells and a reduction in symptoms. Sometimes, at the start of therapy, SSRIs may increase anxiety temporarily. Older drugs called tricyclic antidepressants (amitriptyline, nortriptyline) may be used also, but they have more side effects than the SSRIs.
SSRIs have to be taken for several weeks before the full benefits of the medications are realized. Patients who have severe symptoms, acute anxiety, or panic attacks may need a faster acting medication to resolve symptoms until the antidepressant starts working.
Benzodiazepines such as alprazolam, clonazepam, or diazepam can help provide immediate relief from anxiety. These drugs enhance the effects of the neurotransmitter GABA in the brain and reduce anxiety, cause sedation, and also have muscle relaxant and anticonvulsant effects. Because of the difference in the drug target, medications like benzodiazepines are more like to be habit-forming, and can cause withdrawal symptoms upon discontinuation. Patients taking benzodiazepines as an adjunct when starting an SSRI should be tapered over several weeks as the SSRI takes effect. In some patients with refractory anxiety, benzodiazepines may need to be taken long term. Some patients may benefit from the additional effects on sleep, muscle relaxation, and control of seizures.
Benzodiazepine abuse is a problem also, and may be overlooked due to the recent increased focus on opioid abuse. Benzodiazepines are abused by users practicing self-medication, and have also been used in criminal activity to sedate victims and facilitate sexual abuse. Flunitrazepam, (a.k.a. roofies) is a benzodiazepine that causes amnesia and is often used in this manner.
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