From the Guidelines
The most rapid-acting antidepressants for anxiety are ketamine and esketamine (Spravato), with ketamine typically administered intravenously at doses of 0.5-1.0 mg/kg over 40 minutes, and esketamine given as a nasal spray at 56-84 mg twice weekly for the first month, then weekly to biweekly, as supported by the most recent study 1 and 1.
Rapid-Acting Antidepressants for Anxiety
These medications can provide relief within hours to days, unlike traditional antidepressants which take weeks. For more accessible options, certain SSRIs like escitalopram (10-20 mg daily) or sertraline (50-200 mg daily) may work faster for anxiety than for depression, often showing benefits within 1-2 weeks, as noted in studies 1 and 1.
Key Considerations
- Benzodiazepines like lorazepam (0.5-2 mg as needed) provide immediate anxiety relief but aren't antidepressants and carry risks of dependence, so they're best used short-term while waiting for antidepressants to take effect.
- These rapid-acting treatments work by quickly modulating glutamate and GABA neurotransmitter systems rather than slowly adjusting serotonin levels.
- Side effects of ketamine/esketamine include dissociation and blood pressure changes, requiring monitoring during administration in controlled settings, as highlighted in study 1.
Additional Options
- SNRIs, such as venlafaxine, are also suggested for social anxiety disorder, as recommended in the Japanese Society of Anxiety and Related Disorders/Japanese Society of Neuropsychopharmacology clinical practice guideline 1 and 1.
- The choice of medication should be governed by considerations such as pharmacokinetics, pharmacodynamics, tolerability, cost, insurance formularies, and unique risks leading to warnings or precautions, as discussed in study 1 and 1.
From the FDA Drug Label
The efficacy of Escitalopram in the acute treatment of Generalized Anxiety Disorder (GAD) was demonstrated in three, 8-week, multicenter, flexible-dose, placebo-controlled studies that compared Escitalopram 10-20 mg/day to placebo in adult outpatients between 18 and 80 years of age who met DSM-IV criteria for GAD In all three studies, Escitalopram showed statistically significant greater mean improvement compared to placebo on the Hamilton Anxiety Scale (HAM-A)
The most rapid-acting antidepressants for anxiety that can be identified from the provided information are:
- Escitalopram: It has been shown to be effective in the acute treatment of Generalized Anxiety Disorder (GAD) in as little as 8 weeks 2. However, the term "most rapid-acting" is not explicitly defined in the provided drug labels, and no direct comparison with other antidepressants is made. Therefore, Escitalopram can be considered a rapid-acting antidepressant for anxiety, but it is unclear if it is the most rapid-acting compared to other options.
From the Research
Rapid-Acting Antidepressants for Anxiety
- Ketamine has been shown to have rapid onset activity in treatment-resistant depression, post-traumatic stress disorder, and obsessive-compulsive disorder, with reduced anxiety reported by patients within 1 hour of dosing 3.
- A dose-response profile was noted for anxiolytic effects, dissociative side effects, and changes in blood pressure and heart rate, with minor changes at 0.25 mg/kg, and progressively greater and more durable changes at the higher doses 3.
- Benzodiazepines, such as alprazolam and clonazepam, have been found to have antipanic and antiphobic activity, with effects comparable to but more rapid than antidepressants 4.
- Ketamine may be a potential therapeutic alternative for patients with refractory generalized anxiety disorder/social anxiety disorder, with broad efficacy in disorders characterized by negative emotional states 3, 5.
- Esketamine, a derivative of ketamine, has also been found to be an effective rapid-acting antidepressant, with common adverse events including dissociation, anxiety, nausea, increased blood pressure, and headache 6.
Comparison of Treatment Options
- Selective serotonin reuptake inhibitors (SSRIs) are associated with a delay of several weeks in onset of therapeutic effect and have the potential to exacerbate anxiety and panic early in the treatment course 7.
- Benzodiazepines present rapid onset of action, but can cause tolerance and dependence, highlighting the need for careful consideration of the risks and benefits of each treatment option 7.
- Head-to-head comparisons of SSRIs and benzodiazepines are limited, and future studies should aim to provide more direct comparisons of the risks, benefits, and limitations of each group 7.