What are Anxiety Disorders and Facts
Anxiety disorders are classified into different categories such as generalized anxiety disorder (GAD), panic disorder, social anxiety disorder(SAD), and phobias. Obsessive-compulsive disorder (OCD) and post-traumatic stress disorder (PTSD) are also closely related to anxiety disorders. Generalized anxiety disorder is described as excessive worrying about everyday things. Panic disorder is described as "out of the blue" panic attacks that happen unexpectedly and even possibly during sleep. Social anxiety disorder is characterized as extreme fear of being judged by others in social situations. Obsessive-compulsive disorder (OCD) is described as unwanted thoughts (obsession) that cause a person to repeatedly perform a routine (compulsion) to ease their anxiety. PTSD occurs in people who have witnessed or experienced a traumatizing event causing them to have flashbacks or nightmares.
Here are some interesting facts about anxiety disorders:
Recommended Anxiety Medications by Type of Disorder
The following recommendations for treatment of anxiety disorders are from the World Federation of Societies of Biological Psychiatry (WFSBP) guidelines published in 2012. This guideline is based on analyzing relevant data from 510 clinical trials that showed drug effectiveness over placebo. Using this data, recommendations were based on both evidence and risk versus benefit of each anti-anxiety medication.
Generalized anxiety disorder: The first line of treatment for GAD are selective serotonin reuptake inhibitor (SSRIs), serotonin-norepinephrine reuptake inhibitor (SNRIs), and Lyrica (pregabalin). Other treatment options include buspirone and hydroxyzine.
Panic disorder: The first treatment option for panic disorder are SSRIs and venlafaxine (Effexor). Benzodiazepines may be needed for severe panic attacks to relieve symptoms.
Social Anxiety Disorder: The recommendations for SAD are SSRIs and venlafaxine. Benzodiazepines have not been studied enough for recommendation at this time. Evidence is lacking for use of tricyclic-antidepressants (TCAs) for treating SAD. SAD is usually a chronic disorder and should be treated long term.
Obsessive Compulsive Disorder: SSRIs and clomipramine are preferred treatment options for OCD. OCD requires long-term treatment at a dose where the patient "feels well".
Post-Traumatic Stress Disorder: First line treatments for PTSD are SSRIs and venlafaxine. Fluoxetine and sertraline are effective for long term treatment. PTSD should be treated for at least 12-24 months.
Overview of Drugs for Anxiety
Below is a quick review of drugs for anxiety disorders.
Selective serotonin reuptake inhibitor (SSRIs) block serotonin (a chemical produced by nerve cells that can influence mood) from being reabsorbed into nerve cells and broken down. This causes more serotonin to be available which helps to improve mood. It may take up to 2-4 weeks to show full effectiveness.
Warnings and precautions for SSRIs include monitoring of worsening or unusual change in behavior, slow reduction in dose if discontinuing treatment, risk of bleeding, and avoidance of alcohol consumption. Patients with a history of mania may experience manic episodes and there is a risk of serotonin syndrome if combined with other serotonergic medications. Side effects of SSRIs include nausea, diarrhea, headache, fatigue, drowsiness, insomnia, weight loss, sexual dysfunction, serotonin syndrome, and suicide risk. Some of their drug interactions include interactions with monoamine oxidase inhibitors (for example, selegiline), tryptophan, St. John's Wort, NSAIDs, warfarin, and aspirin. Examples of drugs in this class include Lexapro, Celexa, Paxil, Prozac, and Zoloft.
Lexapro (escitalopram) 5 mg, 10 mg, 20 mg
Lexapro is FDA approved for the treatment of generalized anxiety disorder. In three 8 weeks studies of Lexapro (10-20mg) against placebo, Lexapro produced greater reduction in symptoms of anxiety. The initial dose for Lexapro is 10 mg once daily which can be increased to 20 mg once daily.
Celexa (citalopram) 10 mg,20 mg, 40 mg
Celexa is an antidepressant medication that can also be used to treat anxiety disorders. The usual starting dose of Celexa is 20 mg once daily and can be increased up to 40 mg.
Paxil (paroxetine) 10 mg, 20 mg, 30 mg, 40 mg or Paxil CR 12.5 mg, 25 mg, 37.5 mg
Paxil is FDA approved for the treatment of several types of anxiety such as generalized anxiety disorder, obsessive-compulsive disorder, panic disorder, post-traumatic stress disorder, and social anxiety disorder. In clinical trials, 64% of the patients treated with Paxil showed improvement compared to 34.7% patients receiving placebo. The usual dosing for Paxil is 20 mg once daily and the dose may be increased by increments of 10 mg. The usual dosing for Paxil CR is 12.5 mg once daily and may increase by increments of 12.5 mg.
Prozac (fluoxetine) 10 mg, 20 mg, 40 mg
Prozac is FDA approved for treatment of OCD and panic disorder. In two 13-week studies for the treatment of OCD, Prozac (20 mg, 40 mg, 60 mg) showed a 20% increase in much improvement compared to placebo. At the end of follow up 64% of patients treated with Prozac (10 mg to 60 mg) were free of panic attacks compared to 44% of patients treated with placebo. The usual dosing of Prozac is 20 mg in the morning. For panic disorder the dosage is 10 mg in the morning.
Zoloft (sertraline) 25 mg, 50 mg, 100 mg
Zoloft is FDA approved for several types of anxiety disorders including panic disorder, OCD, PTSD, and social anxiety disorder. In clinical trials, Zoloft has was more effective than placebo in the treatment of OCD, PTSD, social anxiety disorder, and panic disorder. The usual starting dose for Zoloft is 25 mg once daily and can be increased to a max dose of 200 mg.
Serotonin-norepinephrine reuptake inhibitor (SNRIs) block both serotonin and norepinephrine from being reabsorbed into nerves. Allowing more serotonin and norepinephrine to be available, which improves mood. This class of drugs can also be used to treat depression and anxiety disorders. It may take up to 4 to 6 weeks for full effectiveness. Some common side effects of SNRIs are nausea, diarrhea, constipation, increased sweating, headache, dizziness, insomnia, drowsiness, and fatigue. Some serious side effects include high blood pressure, Stevens-Johnson syndrome, bleeding, liver failure, suicide, and serotonin syndrome. Some drug-drug interactions include cimetidine, ciprofloxacin, fluvoxamine, paroxetine, NSAIDs, warfarin, aspirin, and monoamine oxidase inhibitors (MAOIs).
Effexor XR (venlafaxine) 37.5 mg, 75 mg, 150 mg
Effexor is FDA approved for the treatment of anxiety disorders which includes GAD, social anxiety disorder, and panic disorder. In a clinical trial for the treatment of GAD Effexor XR 37.5 mg was more effective than placebo. In several clinical trials for the treatment of social anxiety disorder and panic disorder Effexor XR 75 mg was more effective than placebo in reducing anxiety and number of panic attacks. The usual starting dose of Effexor XR is 37.5 to 75 mg once daily and may be increased by 75 mg weekly if needed.
Cymbalta (Duloxetine) 30 mg, 60 mg
Cymbalta is FDA approved for the treatment of GAD. In 3 clinical trials Cymbalta 60 to 120 mg was more effective than placebo. The usual starting dose of Cymbalta is 60 mg once daily and may be increased to 120 mg once daily. An initial dose of 30 mg once daily can also be used if a patient does not tolerate the drug.
Benzodiazepines are used for short-term treatment of anxiety. This drug class works through binding to GABA receptors. GABA is a neurotransmitter that promotes relaxation and benzodiazepines enhance its effects. Some common side effects include drowsiness, light-headedness, fatigue, dizziness, dry mouth, constipation, nausea, coordination problem, and confusion. Benzodiazepines require gradual dose reduction when discontinuing due to serious withdrawal side effects such as seizures. Alcohol consumption increases the sedative effect of benzodiazepines. Benzodiazepines increase suicide risk, can cause liver failure, and they are associated with dependence and abuse if used long term. Benzodiazepines may interact with fluoxetine, propoxyphene, oral contraceptives, diltiazem, erythromycin, clarithromycin, isoniazid, carbamazepine, and amiodarone. Benzodiazepines used for treatment of anxiety include Xanax, Klonopin, Ativan, and Valium.
Xanax (alprazolam) 0.25 mg, 0.5 mg, 1 mg, 2 mg
Xanax is FDA approved for the treatment of anxiety and panic disorder. In a 4 week clinical trial, Xanax (up to 4 mg) was more effective than placebo for reduction of anxiety. In 3 clinical studies for the treatment of panic attacks 37 to 83% of patients treated with Xanax had no panic attacks. For anxiety the usual starting dose is 0.25 to 0.5 mg three times a day and may increase every 3 or 4 days up to a maximum dose of 4 mg in divided doses. For panic disorder the dose is 0.5 mg three times a day. The usual dosage range is 1 to 10 mg/day.
Klonopin (clonazepam) 0.125 mg, 0.25 mg, 0.5 mg, 1 mg, 2 mg
Klonopin is FDA approved for the treatment of panic disorders. In two clinical trials (9-week and 6-week) Klonopin was more effective than placebo. At the end of treatment 74% of patients treated with Klonopin (0.5 mg to 4 mg) were free of panic attacks compared to 56% of patients treated with placebo. In a 6-week trial, 62% of patients treated with Klonopin (0.5 mg to 4 mg) were panic attack free compared to 37% of patients treated with placebo. The usual starting dose of Klonopin is 0.25 mg twice daily for 3 days, then increased to 1 mg daily.
Ativan (lorazepam) 0.5 mg, 1 mg, 2 mg
Ativan is FDA approved for the treatment of GAD and excessive anxiety prior to surgery. For GAD the usual starting dose for Ativan is 2 to 3 mg divided into 2 or 3 doses and may be increased to 6 mg divided into 2 or 3 doses. For anxiety prior to surgery, the dose is Ativan 0.5 mg intramuscularly 2 hours before surgery.
Valium (Diazepam) 2 mg, 5 mg, 10 mg
Valium is FDA approved for the treatment of anxiety disorders. The usual starting dose for Valium is 2 to 10 mg twice to four times daily depending on severity of anxiety.
Tricyclic antidepressants (TCAs) are also effective for the treatment of anxiety disorders. These medications work through several different mechanisms. Their main mechanism of action is prevention of neurotransmitters (serotonin and norepinephrine) from degrading, which improves mood. They can be used long term compared to the short term use of benzodiazepines. Examples of TCAs used for treatment of anxiety are amitriptyline, Tofranil (imipramine) and Anafranil (clomipramine). Their side effects include sedation, dry mouth, constipation, abnormal heart rhythm, and weight gain. TCAs are lethal in overdose cases and have more side effects than SSRIs and SNRIs.
Lyrica (Pregabalin) is a calcium channel modulator and is effective for treatment of GAD. It affects the release of neurotransmitters from nerves and its effects occur within a few days. Its main side effects are dizziness and drowsiness.
Hydroxyzine is a very sedating antihistamine that is effective for GAD. It is used when its sedating effects are desired or when other medications have failed. Its main side effects are sedation, confusion, dry mouth, delirium, and other anticholinergic side effects.
Atypical Antipsychotics: Quetiapine (Seroquel) and risperidone (Risperdal) have been used for treating GAD or combined with other medications in severe and treatment resistant anxiety disorder cases. Due to their side effects they are reserved for when other options have failed.
List of Recommended Anxiety Medications
Selective Serotonin Reuptake Inhibitors (SSRIs)
Serotonin-norepinephrine Reuptake Inhibitor (SNRIs)
Effexor XR (venlafaxine)
Tricyclic Antidepressants (TCAs)
Other Anti-anxiety Medications
Bandelow, Borwin, Leo Sher, Robertas Bunevicius, Eric Hollander, Siegfried Kasper, Joseph Zohar, and Hans-Jürgen Möller. "Guidelines for the Pharmacological Treatment of Anxiety Disorders, Obsessive–compulsive Disorder and Posttraumatic Stress Disorder in Primary Care."International Journal of Psychiatry in Clinical Practice 16.2 (2012): 77-84.