Medications:

Selective serotonin-reuptake inhibitors (SSRIs), or the serotonin-norepinephrine reuptake inhibitor (SNRI) venlafaxine (Effexor), are the primary first-line treatment for anxiety disorders. For patients who are not helped by these drugs, benzodiazepines, either alone or in combination with an antidepressant, may be prescribed. Other types of antidepressants, including tricyclic antidepressants and monoamine oxidase inhibitors (MAOIs), may also be used to treat patients with severe or chronic forms of anxiety disorders.

Drug therapies for anxiety disorders work best in combination with cognitive behavioral therapy.

Antidepressants

Selective Serotonin Reuptake Inhibitors (SSRIs). SSRIs include fluoxetine (Prozac), sertraline (Zoloft), paroxetine (Paxil), fluvoxamine (Luvox), citalopram (Celexa), and escitalopram (Lexapro).

SSRIs can cause agitation, nausea, and diarrhea. Sexual function side effects include low sex drive, inability to have an orgasm, and impotence. Over time, many SSRI-treated patients gain weight, although the degree of weight gain varies depending on the drug. Elderly people taking these drugs should take the lowest effective dose possible, and those with heart problems should be monitored closely.

There have been many concerns about SSRIs and increased risk for suicidal behavior. Both adults and children who are treated with SSRIs should be carefully monitored for any worsening of depressive symptoms or changes in behavior. This is especially important during the first few months of antidepressant treatment.

Paroxetine has been linked to heart-related birth defects when women took this drug during the first trimester of pregnancy. Experts are also advising caution in prescribing other types of SSRIs to pregnant women. While certain SSRIs may carry increased risks for some specific type of rare birth defects, research suggests that the overall risks are minimal. Still, women who are pregnant or who are considering becoming pregnant should discuss the potential risks of these drugs with their doctors.

Serotonin-norepinephrine reuptake inhibitors (SNRIs). SNRIs are known as dual inhibitors because they work on two neurotransmitters -- norepinephrine and serotonin. Venlafaxine (Effexor) is an SNRI that is approved for treatment of generalized anxiety disorder, social anxiety disorder, and panic disorder in adults. (It is not approved for children.) As with many SSRIs, venlafaxine impairs sexual function. Venlafaxine can increase blood pressure and heart rate and should be used with caution in patients with high blood pressure or heart disease. Some patients report severe withdrawal symptoms, including dizziness and nausea. This drug has a serious risk for overdose. Venlafaxine should not be taken during the last trimester of pregnancy because the drug can cause complications in newborn infants.

Duloxetine (Cymbalta) also acts on both serotonin and norepinephrine. In 2007, it was approved for treatment of generalized anxiety disorder. Side effects are generally mild and include dry mouth, nausea, and sleepiness. Patients with narrow-angle glaucoma or patients with liver or kidney diseases should not take duloxetine. Because duloxetine can cause liver damage, patients who drink large quantities of alcoholic beverages should not take it.

Mitrazapine (Remeron) is another type of SNRI that is sometimes used for treatment of post-traumatic stress disorder and social anxiety disorder.

Tricyclic Antidepressants. Tricyclics are an older type of antidepressant. Tricyclics used for treatment of anxiety disorder include imipramine (Tofranil, for generalized anxiety disorder, panic disorder), nortriptyline (Pamelor, for panic disorder), desipramine (Norpramin, for panic disorder), and clomipramine (Anafranil, for obsessive compulsive disorder). Clomipramine is approved specifically for OCD, but because of its severe side effects it is usually used only if SSRIs have failed to help.

Side effects of TCAs include sleep disturbance, abrupt reduction in blood pressure upon standing, weight gain, sexual dysfunction, and mental disturbance. Elderly patients and those with a history of seizures, cardiac problems, closed-angle glaucoma, and urinary retention or obstruction should be closely supervised when taking tricyclics.

Monoamine Oxidase Inhibitors. Monoamine oxidase inhibitors (MAOIs) are the oldest type of antidepressant. The MAOI phenelzine (Nardil) is sometimes used to treat social anxiety disorder or post-traumatic stress disorder that has not responded to other treatments.

MAOIs commonly cause weight gain, drowsiness, dizziness, sexual dysfunction, and insomnia. Dietary restrictions are the main problem with these drugs. Severe high blood pressure (hypertension) can be brought on by eating certain foods that have a high tyramine content, including cheese, red wine, and processed meats. High blood pressure can also occur when MAOIs are taken with certain drugs, including some common over-the-counter cough medications and decongestants. MAOIs can cause birth defects and should not be taken by pregnant women.

Most serious, fatal reactions can occur when MAOIs and SSRIs or venlafaxine are taken at the same time. There should be at least a 2- to 5-week break if a patient is changing from one type of antidepressant to the other.

Benzodiazepines

Benzodiazepines are safe and effective medications for most anxiety disorders and have been the standard of treatment for years. However, their on-going use has been associated with a high risk for dependency and abuse. Therefore, they have been supplanted in most cases by SSRIs and other newer antidepressants. For anxiety disorders, benzodiazepines are most often used to treat panic disorder, and are sometimes used for social anxiety disorder and generalized anxiety disorder. These drugs include alprazolam (Xanax), clonazepam (Klonopin), and lorazepam (Ativan).

Benzodiazepines have many side effects, generally associated with chronic use. The most common are daytime drowsiness and a hung-over feeling. In rare cases, they can cause agitation. They may worsen respiratory problems. Benzodiazepines are potentially dangerous when used in combination with alcohol. Overdoses can be serious, although they are very rarely fatal.

The elderly are more susceptible to side effects and should usually start at half the dose prescribed for younger people. These drugs increase the risk of falling, which can increase the risk for hip fracture in older people. Also of concern are studies showing a high risk of automobile accidents in people who take benzodiazepines. Benzodiazepines taken during pregnancy are associated with birth defects, and they should not be used by pregnant women or by nursing mothers.

Loss of Effectiveness and Dependence. Eventually these drugs can lose their effectiveness with continued use at the same dosage. As a result, patients may want to increase their dosage to prevent anxiety. This causes dependency, which can occur after taking these drugs for several weeks.

Withdrawal and its Treatments. Withdrawal symptoms can be very severe, even in people who rapidly discontinue benzodiazepines after taking them for only 4 weeks. Symptoms include sleep disturbance and anxiety, which can develop within hours or days after stopping the medication. Some patients experience stomach distress, sweating, and insomnia, which can last 1 - 3 weeks. The longer the drugs are taken and the higher their dose, the more severe these symptoms can become. Simply tapering off gradually helps about 60% of people stop taking these drugs. Certain medications (anti-seizure drugs, antidepressants, buspirone) may also help with withdrawal.

Azapirones (Buspirone)

Azapirones, such as buspirone (BuSpar), act on serotonin receptors called 5-HT(1A). Buspirone appears to work as well as a benzodiazepine for treating generalized anxiety disorder. It usually takes several days to weeks for the drug to be fully effective. It is not useful against panic attacks.

Buspirone does not produce any immediate euphoria or change in sensation, so some people believe, erroneously, that the drug doesn't work. Such qualities result in a very low potential for abuse. In fact, unlike the benzodiazepines, buspirone is not addictive, even with long-term use, so it may be particularly useful for the patient whose anxiety disorder coexists with alcoholism or drug abuse.

Buspirone also seems to have less pronounced side effects than benzodiazepines and no withdrawal effects, even when the drug is discontinued quickly. Common side effects include dizziness, drowsiness, and nausea. Buspirone should not be used with monoamine oxidase inhibitors (MAOIs).

Beta-Blockers

Beta-blockers, including propranolol (Inderal) and atenolol (Tenormin), block the nerves that stimulate the heart to beat faster. They affect only the physiologic symptoms of anxiety (particularly rapid heart rate) and are most helpful for phobias, particularly performance anxiety. They may be taken before entering a situation where anxiety symptoms tend to occur. Beta-blockers are less effective for other forms of anxiety.

Atypical Antipsychotics

Atypical antipsychotics are mostly used for treating schizophrenia, bipolar disorder, and major depressive disorder. Doctors sometimes use the atypical antipsychotic olanzapine (Zyprexa) for treating severe cases of post-traumatic stress disorder. However, olanzapine has severe side effects, including weight gain and increased high blood sugar levels, which can increase the risk for diabetes. [For more information, see In-Depth Report #47: Schizophrenia.]

Anticonvulsants

Pregabalin (Lyrica) and gabapentin (Neurontin) are drugs used to treat seizures and other conditions. Researchers are investigating whether these drugs may be useful for certain anxiety disorders, such as social anxiety disorder and general anxiety disorder. Their exact role in the treatment of anxiety disorders is not clear, however.

Herbs and Supplements

Generally, manufacturers of herbal remedies and dietary supplements do not need FDA approval to sell their products. Just like a drug, herbs and supplements can affect the body's chemistry, and therefore have the potential to produce side effects that may be harmful. There have been a number of reported cases of serious and even lethal side effects from herbal products. Always check with your doctor before using any herbal remedies or dietary supplements.

Studies indicate that the dietary supplement inositol may have benefits for panic disorder and, possibly, obsessive compulsive disorder. Inositol is part of the vitamin B complex.

Some patients use aromatherapy as a relaxation aid. Aromatherapy is in general safe, but some plant extracts in these formulas have been linked to skin allergies.

There is no evidence supporting the efficacy of valerian, St. John’s wort, or passionflower for treatment of anxiety. The herbal remedy kava has been associated with liver problems and should not be avoided, especially by patients with liver disease or those who use alcohol. Kava can also interact dangerously with medications that are metabolized by the liver.