- How Do They Work?
- Different Types
- Side Effects & Warnings
- Drug Interactions
- Example Anxiety Medications
What are anxiety medications and how do they work?
Anxiety is a normal and useful response to potentially stressful or dangerous situations. It increases our awareness of what's going on around us. For most people, anxiety is short-lived and normally goes away once the situation has passed. This is not the case for an estimated 40 million adults in the United States who have some type of anxiety disorder and experience ongoing and unwarranted psychological distress. That distress may also manifest itself in physical symptoms such as muscle tension, headaches, or chest pain.
Anxiety medications include multiple types of drugs that are used to treat the symptoms of anxiety disorders. The three most commonly prescribed types of anxiety medication are
- anti-anxiety medications (also known as anxiolytics), and
Antidepressants and anxiolytic medications work primarily by affecting the balance of certain chemicals in the brain known as neurotransmitters. Beta-blockers and other types of drugs are used to address the physical symptoms that may accompany an anxiety attack. First-generation antihistamines are also used to help with anxiety symptoms because they have a sedating effect.
Anxiety disorders are associated with certain chemical imbalances in the brain involving neurotransmitters such as
- norepinephrine, and
- gamma-aminobutyric acid or GABA.
These chemicals are associated with an individual's sense of well-being or with the ability to relax.
- Anxiety medications can't cure an anxiety disorder, but altering the level of these chemicals, antidepressants and anti-anxiety drugs help control the psychological symptoms.
- Beta-blocking drugs work by blocking the receptors that are associated with some of the physiological symptoms of anxiety -- including rapid heartbeat.
For what conditions are anxiety medications used?
Anxiety medications are used either alone or in combination with psychotherapy to treat a number of different disorders all classified as “anxiety disorders.” These include:
Which anxiety medication is used depends on the specific diagnosis:
- Antidepressants known as selective serotonin reuptake inhibitors (SSRIs) are used to treat panic disorder, obsessive-compulsive disorder, social anxiety disorder, general anxiety disorder, and post-traumatic stress disorder.
- Tricyclic antidepressants (TCAs) are used in treating panic disorder, post-traumatic stress disorder, and general anxiety disorder. One tricyclic, clomipramine (Anafranil), may also be used to treat obsessive-compulsive disorder.
- The antidepressants known as monoamine oxidase inhibitors (MAOIs) are used for panic disorder, social anxiety disorder, and post-traumatic stress disorder.
- Other antidepressants, including serotonin-norepinephrine reuptake inhibitors (SNRIs), are used for panic disorder, obsessive-compulsive disorder, social anxiety disorder, general anxiety disorder, and post-traumatic stress disorder.
- Buspirone (BuSpar), an anti-anxiety drug, is used in the treatment of general anxiety disorder.
- Benzodiazepines are used to treat general anxiety disorder, social anxiety disorder, and panic disorder.
- First-generation antihistamines, such as diphenhydramine, can be used to treat general anxiety disorder.
- Beta-blockers, such as propranolol, are used to treat performance anxiety, a kind of social anxiety disorder, and are sometimes used for panic disorder.
- Alpha-blockers, such as prazosin, are used in treating post-traumatic stress disorder, specifically for nightmares.
- Other drugs, such as anticonvulsants and antipsychotics are used as augmentation therapy to increase the overall response to therapy when symptoms persist after receiving treatment with first-line anti-anxiety drugs.
Are there differences among anxiety medications?
Anxiety medications in the same drug class work in a similar way and there are similarities between classes of anxiety medications.
- SSRIs affect brain serotonin levels. They are the first line for treating most types of anxiety.
- Other antidepressants, including tricyclics (TCAs) and monoamine oxidase inhibitors (MAOIs), that also act on brain serotonin and norepinephrine levels have more limited use because of their side effects and drug interactions.
The anxiolytic drugs, which specifically target these disorders, work in different ways and have specific treatment applications.
- Benzodiazepines act on the neurotransmitter gamma-aminobutyric acid (GABA).
- Buspirone (BuSpar) enhances the activity of serotonin.
- The antihistamine hydroxyzine (Atarax, Vistaril), has a sedative effect by blocking certain receptors in the brain.
Medications normally used to treat high blood pressure also have specific off-label uses for treating panic disorders.
- The beta-blockers propranolol (Inderal) and atenolol (Tenormin) have become a popular remedy for performance anxiety, also known as stage fright. They may also have some use in PTSD.
- The alpha-blocker prazosin (Minipress) eases nightmares from PTSD.
- Other alpha-blockers, such as clonidine (Catapres) and guanfacine (Tenex), may also be useful for treating PTSD.
What are the warnings/precautions/side effects of anti-anxiety medications?
- All antidepressants may increase the risk of suicide in children, adolescents, and young adults up to the age of 24. Also, using other antidepressants with MAO inhibitors poses the serious risk of developing severe, possibly fatal side effects. A space of 14 days needs to be allowed between the use of the two types of drugs.
- Abrupt withdrawal of selective serotonin reuptake inhibitors (SSRIs) and serotonin-norepinephrine reuptake inhibitors (SNRIs) may result in anxiety, confusion, dizziness, and agitation.
- Other drugs that interfere with coagulation, including aspirin and other nonsteroidal anti-inflammatory medications, should be avoided when using SSRIs and SNRIs.
- Combining SSRIs or SNRIs with tryptophan, migraine drugs known as triptans, and other drugs that increase serotonin levels may lead to a serious, life-threatening reaction.
- Some SSRIs and SNRIs may cause a drop in blood sodium levels, especially in dehydrated patients, the elderly, or those using diuretics.
- If a patient develops a rash while using fluoxetine (Prozac), the medication should be discontinued, as this might indicate a serious allergic or other reaction. Fluoxetine commonly causes insomnia and may cause significant weight loss.
- Duloxetine (Cymbalta) can cause liver damage and should not be used by alcohol abusers or by those with pre-existing liver disease. It may also cause dizziness on standing or even fainting early in therapy.
- Venlafaxine (Effexor) may significantly increase cholesterol levels. It may also decrease appetite and cause weight loss. Some patients may experience a sustained increase in blood pressure when using venlafaxine. And venlafaxine should be used with caution in patients with glaucoma.
- Mirtazapine (Remeron) may rarely cause a serious blood disorder called agranulocytosis. If fever, sore throat, or other signs of infection develop while on mirtazapine, and white blood cell counts are elevated, the medication should be discontinued. Mirtazapine may cause an increase in appetite and weight gain. It may also cause drowsiness and/or dizziness. And it can increase cholesterol and triglyceride levels as well as affect liver enzyme levels.
- Some tricyclic antidepressants (TCAs) may cause drowsiness. Anticholinergic side effects commonly occur with TCAs. These include dry mouth, urinary retention, blurry vision, and constipation. TCAs also interact with a wide array of drugs, sometimes with fatal results. Additionally, TCAs are a significant cause of death from drug overdoses.
- Patients with cardiac disease may need to avoid the use of tricyclic antidepressants, and TCAs should not be used in the recovery period immediately following a heart attack.
- TCAs should be used with caution in patients with glaucoma and a history of seizures.
- With monoamine oxidase inhibitors, it's important to monitor blood pressure during therapy. If palpitations or headaches occur while MAOIs are being used, treatment should be stopped, as these may be signs of a potentially fatal hypertensive crisis.
- Foods containing tyramine should not be eaten while using MAOIs. Doing so may trigger a hypertensive crisis. These would include foods smoked, aged, pickled, or fermented -- or food with natural bacterial contamination. Examples of such foods include beer, wine, yeast, liver, dry sausages, fava beans, and yogurt.
- MAOIs interact with a wide array of prescription and nonprescription drugs. Patients should make sure doctors and other health care professionals know they are using these medications.
- Patients using MAOIs may experience drowsiness and dizziness; insomnia is also possible. Other side effects of MAOIs include weight gain, sexual dysfunction, constipation, and other gastrointestinal problems.
- Trazodone (Desyrel) can cause priapism (sustained, painful erections). It can also cause drowsiness. Food significantly affects the absorption of trazodone in some patients. Therefore, trazodone should be taken after a meal or snack.
- Bupropion (Wellbutrin) may increase the risk of seizures, especially at higher doses. It may also cause a significant increase in blood pressure. About one out of every three patients using bupropion experiences insomnia. Bupropion may cause a dry mouth.
- Sweating, constipation, and loss of appetite have been reported with desvenlafaxine. Eye pain, visual changes, and ocular swelling are possible with desvenlafaxine.
- Erectile dysfunction, increased heart rate and/or palpitations, sweating, and constipation are common side effects of levomilnacipran.
- The most common side effect of milnacipran is nausea. Taking it with food can minimize discomfort.
- Atomoxetine may increase suicidal thoughts in teens and children. Other atomoxetine side effects include dizziness, tiredness, mood swings, nausea, vomiting, decreased appetite, trouble urinating, and sexual side effects.
- Nefazodone may increase suicidal thoughts in children and young adults.
Anxiolytics (Anti-Anxiety Medications)
- Benzodiazepines should not be abruptly stopped because of the risk of seizures and other serious side effects. It is dangerous to combine benzodiazepines with other central nervous system depressants, including alcohol. Doing so may cause profound drowsiness and/or impair breathing. Those who have breathing difficulties such as sleep apnea or chronic obstructive pulmonary disease (COPD) should not use benzodiazepines.
- Benzodiazepines frequently cause drowsiness; therefore, care should be taken when operating machinery or motor vehicles.
- Side effects of antihistamines include drowsiness and dry mouth.
- The anticonvulsant divalproex (Depakote) may cause life-threatening liver and pancreatic toxicities; it is also associated with causing birth defects. Divalproex may interfere with blood coagulation. Lethargy is a common side effect of divalproex, but if it's accompanied by vomiting and confusion it may indicate a more serious problem called hyperammonemia in which blood ammonia levels become elevated.
- Tiagabine (Gabitril) at certain dosage levels, or with increases in dose, may induce seizures even in those who have never had them. It may also cause problems with concentration, drowsiness, and dizziness.
- Anticonvulsant medications should not be withdrawn suddenly because of the risk of seizures.
- In pediatric patients, the anticonvulsant gabapentin (Neurontin) may cause behavioral problems, including restlessness, agitation, and hostility. Gabapentin may cause drowsiness.
- Lamotrigine (Lamictal) has caused life-threatening and disfiguring rashes. At the first sign of rash, the medication should be discontinued. There is no guarantee though, the rash won't continue to progress once the drug is withdrawn. Coagulation problems and other blood-related issues may also occur with this drug. It may increase suicidal thoughts or behaviors. It may cause dizziness and drowsiness.
- Use of the anticonvulsant topiramate (Topamax) may cause metabolic acidosis. Symptoms include fatigue and anorexia. Patients using topiramate should have blood bicarbonate levels monitored.
- Topiramate can cause visual changes, including decreased acuity along with eye pain. This may necessitate withdrawal of the drug to prevent permanent visual loss. Decreased sweating and the resultant increase in body temperature, sometimes severe enough to require hospitalization, may occur with topiramate. Patients should be monitored for sweat output, especially in hot weather. Side effects of topiramate include difficulty concentrating, behavioral changes, and drowsiness.
- Levetiracetam may cause mood swings, hallucinations, and unusual behaviors -- as well as fatigue, weakness, and problems walking or moving.
- Pregabalin commonly causes dizziness as well as sleepiness. It may also cause life-threatening allergic reactions.
- Vigabatrin is under a restricted-use program primarily because it can cause vision loss in anyone who takes it, at any dose. Visual loss commonly includes loss of peripheral vision. Vigabatrin has also been linked to suicidal thoughts.
- Beta-blockers should not be withdrawn suddenly because severe cardiac problems, including heart attacks, may occur. Beta-blockers also should not be used in patients with certain breathing disorders, including bronchitis and emphysema.
- Beta-blockers can mask signs and symptoms of hypoglycemia and overactive thyroid disease. Dizziness and drowsiness can occur with beta-blockers.
- The alpha-blocker prazosin (Minipress) can cause dizziness and lightheadedness, both common side effects. Early in treatment, fainting can occur, especially when standing up.
- The alpha-blockers clonidine (Catapres) and guanfacine (Tenex) may cause dry mouth, drowsiness, dizziness, constipation, sedation, and weakness.
- An increased risk of death is seen in elderly patients with dementia-related psychosis who use antipsychotic drugs. These drugs may also increase the risk of suicidal thinking and behavior in younger patients.
- Movement disorders may develop during the use of antipsychotics. Especially with prolonged use, tardive dyskinesia may become irreversible. Antipsychotics may cause hypoglycemia, which can be life-threatening.
- Neuroleptic malignant syndrome, characterized by high fever, muscular rigidity, and abnormal cardiac symptoms, may occur with antipsychotics.
- Drowsiness is a common side effect of antipsychotics. They may also cause difficulty swallowing. Antipsychotics may interfere with the body's ability to control core temperature, therefore, exercise caution in situations that raise body temperature (strenuous exercise, hot weather).
- The antipsychotic ziprasidone (Geodon) prolongs the QT interval, which could lead to fatal heart arrhythmias in some patients. Ziprasidone should not be given to those with a history of QT prolongation or to those who may be taking other drugs that prolong the QT interval.
- The antipsychotic risperidone (Risperdal) may increase the risk of cerebrovascular events, such as stroke, in elderly patients with dementia-related psychosis.
- Patients taking the antipsychotic quetiapine (Seroquel) should be examined for cataracts and other changes to the eyes. This drug may also cause dizziness, fainting, and drowsiness.
- The antipsychotic olanzapine (Zyprexa) may elevate triglyceride levels and cause weight gain. Common side effects include drowsiness, dry mouth, and dizziness.
What are some drug interactions for anti-anxiety drugs?
- Alprazolam increases blood levels of the antidepressants imipramine and desipramine. Alprazolam may also interact with some calcium channel blockers and with grapefruit juice. Carbamazepine decreases blood levels of alprazolam.
- Combining benzodiazepines with alcohol or other central nervous system depressants can cause increased sedation and potentially dangerous respiratory depression.
- Fluoxetine, propoxyphene, and oral contraceptives increase blood levels of alprazolam (Xanax), as do ketoconazole, itraconazole, nefazodone, fluvoxamine, and erythromycin.
- Oral antifungal agents such as ketoconazole and itraconazole may significantly decrease blood levels of clonazepam (Klonopin).
- Serious side effects, including respiratory arrest, may occur if lorazepam (Ativan) is combined with clozapine. The dosage of lorazepam should be halved when taken with valproate or probenecid.
- Theophylline and aminophylline may affect the sedative effects of lorazepam.
- Several drugs can increase the blood levels of triazolam (Halcion), including isoniazid, oral contraceptives, and ranitidine. Ketoconazole, itraconazole, and nefazodone have a profound effect on triazolam metabolism and should not be taken with it. Grapefruit juice also increases the amount of triazolam in the blood.
- Triazolam may interact with calcium channel blockers, antidepressants, ergotamine, amiodarone, and cyclosporine.
Selective Serotonin Reuptake Inhibitors
- SSRIs should not be used with MAOIs. Additionally, serotonin syndrome may occur if SSRIs are administered with triptan migraine drugs, linezolid (Zyvox), St. John's Wort, lithium, or tramadol. Combining SSRIs with aspirin, other nonsteroidal anti-inflammatory drugs, or warfarin, increases the risk of bleeding.
- Levels of imipramine and desipramine have been shown to significantly increase when taken with certain SSRIs. Combining SSRIs with antipsychotic drugs may result in neuroleptic malignant syndrome, a serious side effect.
- Citalopram (Celexa) may cause a significant rise in blood levels of desipramine and other tricyclic antidepressants.
- Taking fluoxetine (Prozac) with pimozide or thioridazine is contraindicated because of possibly dangerous effects on heart rhythm. Stable levels of phenytoin and carbamazepine may rise to toxic levels if fluoxetine is introduced.
- Plasma levels of pimozide, thioridazine, alosetron, astemizole, cisapride, diazepam, and tizanidine increased significantly when used with fluvoxamine (Luvox). Consequently, these drugs should not be used together. Additionally, dosage adjustments may be required for warfarin, mexiletine, and theophylline when used with fluvoxamine.
- Paroxetine (Paxil) should not be used with pimozide or thioridazine because of possibly dangerous effects on heart rhythm. Digoxin, atomoxetine, risperidone, and theophylline levels may require adjustment when given with paroxetine.
- Sertraline (Zoloft) should not be used with pimozide because of the potential for severe cardiac effects.
- Vilazodone may cause eye pain, visual changes, and swelling in the ocular area.
- Vilazodone and vortioxetine can affect sodium blood levels and coagulation of blood.
Tricyclic Antidepressants (TCAs)
- TCAs should not be used with MAOIs. SSRIs may increase blood levels of TCAs, as may cimetidine. Phenytoin and barbiturates may decrease the blood levels of TCAs. Anticholinergic drugs may worsen some side effects of TCAs.
- Decongestants and other drugs containing catecholamines should not be used with TCAs. The sedative effect of TCAs may be enhanced by alcohol and other CNS depressant drugs.
- MAOIs interact with a wide range of prescription and nonprescription medications, including other antidepressants, anticonvulsants, antihistamines, and decongestants, as well as some foods. Many of these interactions can be fatal. Patients should inform all those involved in their care if they are using MAOIs.
Serotonin Norepinephrine Reuptake Inhibitors (SNRIs)
- SNRIs should not be used with MAOIs.
- Heavy alcohol use with duloxetine (Cymbalta) may result in liver injury.
- Bupropion (Wellbutrin) should not be used with the MAOI phenelzine. Use caution when bupropion is taken with drugs known to lower the seizure threshold (for example, theophylline or steroids). The use of bupropion with nicotine transdermal systems may result in hypertension.
- HIV drugs (such as ritonavir), as well as oral antifungals (for example, ketoconazole) increase plasma levels of trazodone (Desyrel). Carbamazepine reduces blood levels of trazodone. Blood levels of phenytoin and digoxin increased when given with trazodone.
Antihistamines may cause increased drowsiness when used with CNS depressants.
Large amounts of grapefruit juice may increase blood levels of buspirone. Other drugs that affect blood levels of buspirone include oral antifungals, calcium channel blockers, certain antibiotics (Erythromycin and Rifampin), and nefazodone (Serzone).
Gabapentin (Neurontin) may affect blood levels of hydrocodone and morphine. Gabapentin levels can decrease when given with the antacid Maalox. Allow 2 hours between the drugs.
The following medications significantly decrease blood levels of lamotrigine (Lamictal): oral contraceptives, phenobarbital, primidone, phenytoin, carbamazepine, oxcarbazepine, and rifampin.
The following medications decrease topiramate (Topamax) levels: phenytoin, carbamazepine, valproic acid, and lamotrigine. Using topiramate with acetazolamide or dichlorphenamide may increase the risk for kidney stones. Topiramate can interact with some drugs used for diabetes (metformin, pioglitazone), so careful blood sugar monitoring is warranted when they are combined.
The following drugs may significantly increase levels of valproate (Depakote) in the blood: aspirin and felbamate. The following drugs may significantly decrease blood levels of valproate: rifampin, and carbapenem antibiotics (imipenem, meropenem, ertapenem).
Beta-blockers used with other cardiac drugs -- calcium channel blockers, anti-arrhythmic, ACE inhibitors, digitalis -- may result in additive effects on blood pressure and heart rate, sometimes to a dangerous level.
Warfarin concentrations increase when used with propranolol.
Hypotension and cardiac arrest have occurred with the use of haloperidol and propranolol.
Sedation may increase if clonidine (Catapres) and guanfacine (Tenex) are used with other CNS depressants, including alcohol.
Increased drowsiness may occur when aripiprazole (Abilify) is given with other CNS-active drugs. Significant increases in blood levels may occur if given with oral antifungals (ketoconazole). A significant decrease in the blood level of aripiprazole may occur if given carbamazepine.
Ziprasidone (Geodon) should not be used with other drugs known to cause prolongation of the QT interval, such as thioridazine and chlorpromazine.
The effect of blood pressure-lowering medications may be enhanced when taken with either ziprasidone or risperidone (Risperdal). These medications may decrease the effectiveness of levodopa/dopamine agonists. Increased drowsiness may occur if these drugs are combined with other CNS depressants.
Carbamazepine may decrease blood levels of ziprasidone and risperidone; ketoconazole may increase levels of ziprasidone.
The following drugs may significantly increase blood levels of quetiapine (Seroquel): oral antifungals (ketoconazole), certain antibiotics (erythromycin), and protease inhibitors (indinavir). Phenytoin and thioridazine may significantly decrease the blood levels of quetiapine.
Olanzapine (Zyprexa) should be used with caution with other CNS depressant drugs and alcohol. The following drugs may increase blood levels of olanzapine: fluvoxamine, fluoxetine, rifampin, and omeprazole. Carbamazepine may decrease blood levels of olanzapine. Orthostatic hypotension potential may rise if olanzapine is used with diazepam or alcohol, and olanzapine can enhance the blood-pressure-lowering effects of other drugs.
What are some examples of anxiety medications?
Selective Serotonin Reuptake Inhibitors
- Citalopram (Celexa)
- Escitalopram (Lexapro)
- Fluvoxamine (Luvox)
- Paroxetine (Paxil)
- Fluoxetine (Prozac)
- Sertraline (Zoloft)
- Vilazodone (Viibryd)
- Vortioxetine (formerly Brintellix; now Trintellix)
- Maprotiline (Ludiomil)
- Mianserin (Norval)
- Amitryptiline (Elavil)
- Amoxapine (Asendin)
- Clomipramine (Anafranil) )
- Despiramine (Norpramin)
- Doxepin (Adapin, Sinequan)
- Imipramine (Tofranil)
- Nortriptyline (Aventyl, Pamelor)
- Protryptiline (Vivactyl)
- Trimipramine (Surmontil)
Monoamine Oxidase Inhibitors
- Isocarboxazid (Marplan)
- Phenelzine (Nardil)
- Selegiline (Emsam Patches)
- Tranylcypromine (Parnate)
Serotonin Norepinephrine Reuptake Inhibitors
- Desvenlafaxine (Pristiq)
- Duloxetine (Cymbalta)
- Levomilnacipran (Fetizma)
- Milnacipran (Savella)
- Mirtazapine (Remeron)
- Venlafaxine (Effexor)
- Atomoxetine (Strattera)
- Bupropion (Wellbutrin)
- Nefazodone (Serzone)
- Trazodone (Desyrel)
- Alprazolam (Xanax)
- Chlordiazepoxide (Librium)
- Clobazepam (Onfi)
- Clonazepam (Klonopin)
- Clorazepate (Tranxene)
- Diazepam (Valium)
- Estazolam (ProSom)
- Flurazepam (Dalmane)
- Lorazepam (Ativan)
- Midazolam (Versed)
- Oxazepam (Serax)
- Prazepam (Centrax)
- Quazepam (Doral)
- Temazepam (Restoril)
- Triazolam (Halcion)
- Hydroxyzine (Atarax, Vistaril)
- Buspirone (BuSpar)
- Carbamazepine (Tegretol)
- Gabapentin (Neurontin)
- Leveteriacetam (Keppra)
- Lamotrigine (Lamictal)
- Pregabalin (Lyrica)
- Tiagabine (Gabitril)
- Topiramate (Topamax)
- Valproic Acid (Depakote)
- Vigabatrin (Sabril)
- Propranolol (Inderal)
- Atenolol (Tenormin)
- Note: There are many other beta-blockers, but the two above are indicated for social anxiety.
- Prazosin (Minipress)
- Clonidine (Catapres)
- Guanfacine (Tenex)
- Aripiprazole (Abilify)
- Olanzapine (Zyprexa)
- Quetiapine (Seroquel)
- Risperidone (Risperdal)
- Ziprasidone (Geodon)
Anxiety Disorders Association of America
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Marina Katz, MD
American Board of Psychiatry & Neurology