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Overview of Anxiety Disorders

By

John W. Barnhill

, MD, New York-Presbyterian Hospital

Reviewed/Revised Aug 2023
View PATIENT EDUCATION

Anxiety disorders are characterized by persistent and excessive fear and anxiety and the dysfunctional behavioral changes a patient may use to mitigate these feelings. Anxiety disorders are differentiated from one another based on the specific objects or situations that induce the fear, anxiety, and associated behavioral changes.

Everyone periodically experiences fear and anxiety.

Fear is an emotional, physical, and behavioral response to an immediately recognizable external threat (eg, an intruder, a car spinning on ice).

Anxiety is a distressing, unpleasant emotional state of nervousness and uneasiness; its causes are less clear. Anxiety is less tied to the exact timing of a threat; it can be anticipatory before a threat, persist after a threat has passed, or occur without an identifiable threat.

People often experience both fear and anxiety as changes in their body (eg, sweating, nausea) and their behaviors (eg, avoidance, anger). Often, people are aware of these physical and behavioral changes without clearly identifying that they are anxious or fearful.

Adaptive anxiety can help motivate people to prepare, practice, and rehearse; it can also encourage appropriate caution in potentially dangerous situations. When anxiety causes dysfunction and undue distress, however, it is considered maladaptive and, thus, a psychiatric disorder.

The Diagnostic and Statistical Manual of Mental Disorders, 5th edition, Text Revision (DSM-5-TR) lists the various anxiety disorders in order of the typical age of onset (3 General references Anxiety disorders are characterized by persistent and excessive fear and anxiety and the dysfunctional behavioral changes a patient may use to mitigate these feelings. Anxiety disorders are... read more ):

Substance-induced/medication-induced anxiety disorder and anxiety due to another medical condition should always be considered when people present with significant anxiety.

General references

  • 1. Bandelow B, Michaelis S: Epidemiology of anxiety disorders in the 21st century. Dialogues Clin Neurosci 17(3):327-335, 2015. doi: 10.31887/DCNS.2015.17.3/bbandelow

  • 2. Penninx BW, Pine DS, Holmes EA, et al: Anxiety disorders. Lancet 97(10277):914-927, 2021. doi: 10.1016/S0140-6736(21)00359-7

  • 3. Diagnostic and Statistical Manual of Mental Disorders, 5th edition, Text Revision (DSM-5-TR). American Psychiatric Association Publishing, Washington, DC, pp 215-262.

Etiology of Anxiety Disorders

There is no single gene or psychological cause for anxiety disorders, but they do seem to develop in the context of typical biopsychosocial factors. Anxiety disorders tend to run in families, and they do so through at least 2 mechanisms (1 Etiology references Anxiety disorders are characterized by persistent and excessive fear and anxiety and the dysfunctional behavioral changes a patient may use to mitigate these feelings. Anxiety disorders are... read more ):

Many people develop an anxiety disorder, however, without an identifiable antecedent trigger. For example, most people with a snake phobia have never been bitten by a snake and do not report a characteristic traumatic experience. Anxiety can also be a response to environmental and social stressors during adulthood, such as the ending of a significant relationship or exposure to a life-threatening disaster, though most people who experience such stressors do not go on to develop an anxiety disorder.

Multiple neurotransmitters are involved in the development of anxiety disorders. The 2 predominant neurotransmitters—GABA and glutamate—play a key role, as do other neurotransmitters like serotonin, norepinephrine, and dopamine. These neurotransmitters play an important role in influencing medication selection.

Some medical disorders can directly cause anxiety. These include asthma Asthma Asthma is a disease of diffuse airway inflammation caused by a variety of triggering stimuli resulting in partially or completely reversible bronchoconstriction. Symptoms and signs include dyspnea... read more , cardiac arrhythmias Overview of Arrhythmias The normal heart beats in a regular, coordinated way because electrical impulses generated and spread by myocytes with unique electrical properties trigger a sequence of organized myocardial... read more Overview of Arrhythmias , chronic obstructive pulmonary disease (COPD) Chronic Obstructive Pulmonary Disease (COPD) Chronic obstructive pulmonary disease (COPD) is airflow limitation caused by an inflammatory response to inhaled toxins, often cigarette smoke. Alpha-1 antitrypsin deficiency and various occupational... read more Chronic Obstructive Pulmonary Disease (COPD) , heart failure Heart Failure (HF) Heart failure (HF) is a syndrome of ventricular dysfunction. Left ventricular (LV) failure causes shortness of breath and fatigue, and right ventricular (RV) failure causes peripheral and abdominal... read more Heart Failure (HF) , hyperthyroidism Hyperthyroidism Hyperthyroidism is characterized by hypermetabolism and elevated serum levels of free thyroid hormones. Symptoms include palpitations, fatigue, weight loss, heat intolerance, anxiety, and tremor... read more Hyperthyroidism , Cushing syndrome Cushing Syndrome Cushing syndrome is a constellation of clinical abnormalities caused by chronic high blood levels of cortisol or related corticosteroids. Cushing disease is Cushing syndrome that results from... read more Cushing Syndrome , and pheochromocytoma Pheochromocytoma A pheochromocytoma is a catecholamine-secreting tumor of chromaffin cells typically located in the adrenals. It causes persistent or paroxysmal hypertension. Diagnosis is by measuring catecholamine... read more .

The medications used to treat some medical disorders can also induce anxiety as a symptom. These include

  • Asthma (albuterol, corticosteroids, theophylline)

  • Attention deficit/hyperactivity disorder (amphetamines and other stimulants)

  • Hyperthyroidism (levothyroxine, liothyronine)

  • Seasonal allergies (antihistamines and decongestants)

  • Seizure disorders (phenytoin)

  • Parkinson disease (levodopa)

In addition, a variety of substances and illicit drugs can directly induce anxiety, including caffeine, cocaine Cocaine Cocaine is a sympathomimetic drug with central nervous system stimulant and euphoriant properties. High doses can cause panic, schizophrenic-like symptoms, seizures, hyperthermia, hypertension... read more , and MDMA (ecstasy Methylenedioxymethamphetamine (MDMA) MDMA (3,4-methylenedioxymethamphetamine) is an amphetamine analog with stimulant and hallucinogenic effects. MDMA acts primarily on neurons that produce and release serotonin, but it also affects... read more ). Some drugs that are generally used to induce relaxation can also cause anxiety. Cannabis Marijuana (Cannabis) Marijuana is a euphoriant that can cause sedation or dysphoria in some users. Psychologic dependence can develop with chronic use, but very little physical dependence is clinically apparent... read more (marijuana) induces anxiety in some people, either directly or through an adulterant such as phencyclidine Ketamine and Phencyclidine (PCP) Ketamine and phencyclidine are N-methyl-D-aspartate receptor antagonists and dissociative anesthetics that can cause intoxication, sometimes with confusion or a catatonic state. Overdose can... read more (PCP). Withdrawal from alcohol Alcohol Toxicity and Withdrawal Alcohol (ethanol) is a central nervous system depressant. Large amounts consumed rapidly can cause respiratory depression, coma, and death. Large amounts chronically consumed damage the liver... read more , sedatives, and some other drugs can also cause anxiety.

COVID-19–related anxiety

The COVID-19 pandemic was associated with surges in rates of depression and anxiety in people who had not been infected (2 Etiology references Anxiety disorders are characterized by persistent and excessive fear and anxiety and the dysfunctional behavioral changes a patient may use to mitigate these feelings. Anxiety disorders are... read more ). Such psychological reactions may have been exacerbations of underlying issues, but the symptoms are often intensified by media exposure, economic hardship, uncertainty regarding the future, fears of infection (for themselves and loved ones), loss of familiar supports (eg, friends, employment), and behavioral restrictions (eg, masks, social distancing).

Symptomatic COVID-19 infection is also associated with increased anxiety (3 Etiology references Anxiety disorders are characterized by persistent and excessive fear and anxiety and the dysfunctional behavioral changes a patient may use to mitigate these feelings. Anxiety disorders are... read more ). The triggers for this increased anxiety can be physiologic (eg, shortness of breath); psychological (eg, immediate fears of death); social (eg, isolation from loved ones); and pharmacologic (eg, corticosteroids are often used in treatment of COVID-19). In addition, it has been hypothesized that COVID-19 induces a host immune response that directly leads to neuropsychiatric symptoms (eg, anxiety, mood changes, neuromuscular dysfunction); these neuropsychiatric reactions may be acute or part of a syndrome known as long COVID. (See also COVID-Related Neuropsychiatric Manifestations COVID-Related Neuropsychiatric Manifestations COVID-19 is primarily an acute respiratory syndrome, but it can also cause dysfunction of multiple organs and body systems, including the brain and peripheral nervous system. COVID-19 can be... read more .)

Etiology references

  • 1. Juruena MF, Eror F, Cleare AJ, et al: The role of early life stress in HPA axis and anxiety. Adv Exp Med Biol 1191:141-153, 2020. doi: 10.1007/978-981-32-9705-0_9

  • 2. Shafran R, Rachman S, Whittal M, et al: Fear and anxiety in COVID-19: Preexisting anxiety disorders. Cogn Behav Pract 28(4):459-467, 2021. doi:10.1016/j.cbpra.2021.03.003

  • 3. Troyer EA, Kohn JN, Hong S: Are we facing a crashing wave of neuropsychiatric sequelae of COVID-19? Neuropsychiatric symptoms and potential immunologic mechanisms. Brain Behav Immun 87:34-39, 2020. doi: 10.1016/j.bbi.2020.04.027

Symptoms and Signs of Anxiety Disorders

Anxiety disorders tend to differ from usual and normal anxiety by being persistent (> 6 months), excessive, debilitating, and uncomfortable.

  • Gastrointestinal: Nausea, vomiting, diarrhea

  • Pulmonary: Shortness of breath, choking

  • Autonomic: Dizziness, faintness, sweats, hot and cold flashes

  • Cardiac: Palpitations, accelerated heart rate

  • Musculoskeletal: Muscle tension, chest pain or tightness

A panic or worry diary can be a useful tool for recording symptoms, both because retrospective anxiety reports can be vague and because treatment strategies often depend on details.

Signs and symptoms reference

  • 1. Craske MG, Stein MB: Anxiety. Lancet 388:3048-3059, 2016. doi: 10.1016/S0140-6736(16)30381-6

Diagnosis of Anxiety Disorders

  • Diagnostic and Statistical Manual of Mental Disorders, 5th edition, Text Revision (DSM-5-TR) criteria

Diagnosis of a specific anxiety disorder is based on its characteristic symptoms and signs according to DSM-5-TR. In general, an anxiety disorder may be suspected when the following apply (1 Diagnosis references Anxiety disorders are characterized by persistent and excessive fear and anxiety and the dysfunctional behavioral changes a patient may use to mitigate these feelings. Anxiety disorders are... read more ):

  • Anxiety is very distressing.

  • Anxiety interferes with functioning.

  • Anxiety does not stop spontaneously within a few days.

  • Other causes are not identified.

When diagnosing an anxiety disorder, it is important to rule out anxiety attributable to certain medical conditions (eg, asthma, hyperthyroidism), and/or substances or medications (2 Diagnosis references Anxiety disorders are characterized by persistent and excessive fear and anxiety and the dysfunctional behavioral changes a patient may use to mitigate these feelings. Anxiety disorders are... read more ). Furthermore, if present, the clinician needs to assess the extent to which the medical disorder and/or substance is actually implicated in the anxiety. As is true in all psychiatric assessments, a careful history is crucial to accurate diagnosis.

If patients meet criteria for an anxiety disorder, and the clinician concludes that the symptoms are best explained by the direct physiologic effects of a medication or illicit drug/substance, the patient is deemed to have a substance-/medication-induced anxiety disorder. Similarly, if the significant anxiety is deemed to be the direct physiologic result of another medical condition, the patient may be diagnosed with anxiety disorder due to another medical condition.

As is true for almost all psychiatric conditions, there are no laboratory tests for anxiety disorders, though laboratory tests may help identify medical conditions associated with the anxiety. Clinical judgment is required before making the diagnosis. In addition to eliciting characteristic symptoms and time course, the clinician must also evaluate whether the clinical situation meets the threshold for causing clinically significant distress and/or dysfunction.

The different anxiety disorders can often be distinguished from one another based on the answers to 3 key questions:

  • What situations induce the fear and anxiety?

  • What thoughts are associated with the anxiety?

  • What avoidance strategies are used?

Cultural factors

Culture influences the expression, conceptualization, and treatment of all psychiatric conditions, including anxiety disorders (3, 4 Diagnosis references Anxiety disorders are characterized by persistent and excessive fear and anxiety and the dysfunctional behavioral changes a patient may use to mitigate these feelings. Anxiety disorders are... read more ). During the psychiatric assessment, it is important to look for ways in which the anxiety symptoms might be affected by the surrounding political, economic, and legal systems, as well as by specific issues related to migrant status, sexual orientation, socioeconomic status, religion, spirituality, and family structures.

Patients may feel intimidated, embarrassed, or reluctant to discuss anxiety with anyone, much less physicians, who may appear to belong to a different and potentially more privileged socioeconomic group. Similarly, people who want to be "good patients" might not be upfront about psychiatric issues if they suspect that their clinicians are too busy to address anything other than their most prominent nonpsychiatric medical issue.

It can also be useful to ask patients what they think is causing their problems. Not all patients believe completely in the medical model, and, if tactfully asked, many patients might reluctantly mention that they (or their relatives) believe their symptoms were induced by a religious or other mystical source (eg, an "evil eye").

Eliciting such information improves the patient-clinician alliance, deepens the understanding of both the patient and the presenting complaints, and improves the likelihood that the patient will be more transparent and adherent going forward.

Diagnosis references

  • 1. Diagnostic and Statistical Manual of Mental Disorders, 5th edition,Text Revision (DSM-5-TR). American Psychiatric Association Publishing, Washington, DC, pp 215-221.

  • 2. Craske MG, Stein MB: Anxiety. Lancet 388:3048-3059, 2016. doi: 10.1016/S0140-6736(16)30381-6

  • 3. Diagnostic and Statistical Manual of Mental Disorders, 5th Edition, Text Revision (DSM-5-TR), Cultural Concepts of Distress. American Psychiatric Association Publishing, Washington, DC, pp 872-880.

  • 4. Lewis-Fernández R, Aggarwal NK, Lam PC, et al: Feasibility, acceptability and clinical utility of the Cultural Formulation Interview: Mixed-methods results from the DSM-5 international field trial. Br J Psychiatry 210(4):290-297, 2017. doi: 10.1192/bjp.bp.116.193862

  • 5. Kaiser BN , Haroz EE, Kohrt BA, et al: "Thinking too much": A systematic review of a common idiom of distress. Soc Sci Med 147:170-183, 2015. doi: 10.1016/j.socscimed.2015.10.044

Treatment of Anxiety Disorders

  • Psychoeducation

  • Relaxation techniques

  • Psychotherapies, such as cognitive-behavioral psychotherapy (CBT)

  • Pharmacotherapy (benzodiazepines, selective serotonin reuptake inhibitors [SSRIs])

The following general principles are important to take into consideration when treating anxiety disorders:

Psychoeducation and relaxation techniques

Psychoeducation is typically fundamental to the treatment of anxiety disorders. It can feel liberating for the patient to understand how a sometimes bewildering array of symptoms and behaviors can be conceptualized into a diagnosis. Education also provides a cognitive structure to help patients pursue a treatment that may feel uncomfortable.

Relaxation techniques should be taught early in the treatment. These techniques are useful both because fear and anxiety are fundamental to anxiety disorders and because the treatment can transiently intensify the disabling thoughts and feelings. Without a tool for controlling anxiety, many patients will not adhere to treatment. Relaxation techniques may include muscle relaxation, breathing management, yoga, hypnosis, and/or meditation, but patient preference is important in determining the specific approach. Relaxation techniques can be briefly described and then "prescribed" as homework. Adherence and effectiveness are more likely to be optimized if the clinician periodically demonstrates the techniques (eg, slow, steady breathing) with enthusiasm.

Psychotherapies

Various psychotherapies are equally efficacious for most psychiatric disorders. This equivalency appears to be related to so-called nonspecific factors, which include the personal characteristics of the therapist and a positive therapeutic climate that allows the patient to effectively engage in the talk therapy and remain adherent with agreed-upon practices and medications.

CBT involves both cognitive restructuring and exposure therapy. Cognitive restructuring begins with the idea that patients with anxiety disorders overestimate the danger (catastrophize) and underestimate their ability to deal with the danger. These inaccurate thoughts and antecedent triggers are clarified during treatment. Often, the pattern of anxiety can be neatly laid into a characteristic cycle of triggers, behaviors, and anxiety. As this cycle is clarified, patients are taught to recognize and confront their inaccurate thoughts (ie, cognitive restructuring).

CBT also focuses on the behavioral elements of the anxiety disorder. Typically, patients with anxiety disorders respond to perceived danger with a "fight-or-flight" response. Some patients with prominent anxiety are able to "fight" their anxiety, often with a counter-phobic response (eg, an actor with prominent social anxiety), but most respond with avoidance. Exposure therapy aims to identify the avoidance behavior and then present the patient with gradually intensifying opportunities to be safely exposed to the fearful trigger, gradually desensitizing the patient.

Other psychotherapies used for treatment of anxiety disorders combine aspects of CBT, relaxation, and mindfulness along with other strategies that appear to be helpful. These treatments include mindfulness-based stress reduction, hypnosis, panic-focused psychodynamic psychotherapy, interpersonal therapy, and supportive psychotherapy:

Pharmacotherapy

Pharmacotherapy is typically helpful in the management of anxiety disorders, especially when used in conjunction with any of the above psychotherapeutic techniques. Antidepressants and benzodiazepines are the 2 medication classes with the strongest evidence base, though there is also a role for nonbenzodiazepine anxiolytics (such as buspirone) and atypical antipsychotics (9 Treatment references Anxiety disorders are characterized by persistent and excessive fear and anxiety and the dysfunctional behavioral changes a patient may use to mitigate these feelings. Anxiety disorders are... read more ).

Selective serotonin reuptake inhibitors Selective Serotonin Reuptake Inhibitors (SSRIs) Several drug classes and drugs can be used to treat depression: Selective serotonin reuptake inhibitors (SSRIs) Serotonin modulators (5-HT2 blockers) Serotonin-norepinephrine reuptake inhibitors... read more (SSRIs) are generally considered first-line based on their efficacy and safety profiles. These "antidepressant" medications address the symptoms of the anxiety disorders regardless of whether there is a comorbid depressive disorder.

SSRI antidepressants are generally started at the lowest available dose to minimize adverse effects. Patients with anxiety may be sensitive to bodily changes and may discontinue treatment if they experience adverse effects early on. Once the patient has tolerated the initial dose, the antidepressant can be gradually increased until a therapeutic dose or therapeutic effect is reached. A positive clinical effect may occur at any time but often takes 6 or more weeks to achieve.

Benzodiazepines may be used for acute relief of anxiety but can create dependence Sedatives Sedatives include benzodiazepines, barbiturates, and related drugs. High doses can cause decreased level of consciousness and respiratory depression, which may require intubation and mechanical... read more and a desire for increasing levels that limit their benefit/risk ratio for chronic use (10 Treatment references Anxiety disorders are characterized by persistent and excessive fear and anxiety and the dysfunctional behavioral changes a patient may use to mitigate these feelings. Anxiety disorders are... read more ). They are often used in conjunction with an antidepressant and psychotherapy. The benzodiazepine can often be tapered once the anxiety symptoms have improved.

Treatment of comorbidities

When present, comorbid substance use disorders and other psychiatric conditions must also be appropriately managed.

Comorbid substance use disorders Substance Use Disorders Substance use disorders involve a pathologic pattern of behaviors in which patients continue to use a substance despite experiencing significant problems related to its use. Diagnosis of substance... read more are often not spontaneously reported (11 Treatment references Anxiety disorders are characterized by persistent and excessive fear and anxiety and the dysfunctional behavioral changes a patient may use to mitigate these feelings. Anxiety disorders are... read more ). Substances such as alcohol, marijuana, and benzodiazepines are often used to self-medicate by those with anxiety disorders. Patients may be reluctant to give up these substances until they trust that the clinician has a viable alternative treatment. Self-medication often leads to a vicious cycle. For example, the alcohol use that quickly reduces anxiety may be followed by rebound anxiety, followed by an increased urgency to self-medicate.

Comorbid bipolar disorder Bipolar Disorders Bipolar disorders are characterized by alternating episodes of mania and depression, although many patients have a predominance of one or the other. Exact cause is unknown, but heredity, changes... read more can cause specific management difficulties. Many people with bipolar disorder are initially misdiagnosed, particularly because they often have far more periods of depression than mania. Treatment with an antidepressant medication may be an appropriate first-line treatment for an anxiety disorder with comorbid major depression Depressive Disorders Depressive disorders are characterized by sadness severe enough or persistent enough to interfere with function and often by decreased interest or pleasure in activities. Exact cause is unknown... read more . However, for an individual with both anxiety and a bipolar disorder, that same medication choice can trigger a manic episode consisting of intensified anxiety and irritability. A missed bipolar disorder can result in decades of inappropriate treatments.

Comorbid medical disorders can also be challenging to manage. For example, asthma can physiologically cause anxiety, but so can some of the medications used to treat asthma. Anxiety can contribute to an asthma exacerbation, and fears of an asthma exacerbation can lead to avoidance behaviors (eg, diminished activity, medication nonadherence) that in turn can exacerbate asthma and lead to a diminished quality of life.

Treatment references

  • 1. Chellappa SL, Aeschbach D: Sleep and anxiety: From mechanisms to interventions. Sleep Med Rev61:101583, 2022. doi: 10.1016/j.smrv.2021.101583

  • 2. Bandelow B, Michaelis S, Wedekind D: Treatment of anxiety disorders. Dialogues Clin Neurosci 19(2):93-107, 2017. doi: 10.31887/DCNS.2017.19.2/bbandelow

  • 3. Cuijpers P, Sijbrandij M, Koole SL, et al: Adding psychotherapy to antidepressant medication in depression and anxiety disorders: a meta-analysis. World Psychiatry, 13(1), 56-67, 2014.doi: 10.1002/wps.20089

  • 4. Szuhany KL, Simon NM: Anxiety disorders: A review. JAMA 328(24):2431-2445, 2022. doi: 10.1001/jama.2022.22744

  • 5. Haller H, Breilmann P, Schröter, M. et al: A systematic review and meta-analysis of acceptance- and mindfulness-based interventions for DSM-5 anxiety disorders. Sci Rep 11(1):20385, 2021. doi: 10.1038/s41598-021-99882-w

  • 6. Valentine KE, Milling LS, Clark LJ, et al: The efficacy of hypnosis as a treatment for anxiety: A meta-analysis. Int J Clin Exp Hyposis 67(3)336-363, 2019. doi: 10.1080/00207144.2019.1613863

  • 7. Barber JP, Milrod B, Gallop R, et al: Processes of therapeutic change: Results from the Cornell-Penn Study of Psychotherapies for Panic Disorder. J Couns Psychol 67(2):222-231, 2020. doi: 10.1037/cou0000417

  • 8. Markowitz JC, Milrod B, Luyten P, et al: Mentalizing in interpersonal psychotherapy. Am J Psychother 72(4):95-100. 2019. doi: 10.1176/appi.psychotherapy.20190021

  • 9. Slee A, Nazareth I, Bondaronek P, et al: Pharmacological treatments for generalised anxiety disorder: A systematic review and network meta-analysis. Lancet 2019393(10173):768-777. doi: 10.1016/S0140-6736(18)31793-8

  • 10. Balon R, Starcevic V: Role of benzodiazepines in anxiety disorders. Adv Exp Med Biol 1191:367-388, 2020. doi: 10.1007/978-981-32-9705-0_20

  • 11. Anker JJ, Kushner MG: Co-occurring alcohol use disorder and anxiety: Bridging psychiatric, psychological, and neurobiological perspectives. Alcohol Res 40(1):arcr.v40.1.03, 2019. doi: 10.35946/arcr.v40.1.03

Drugs Mentioned In This Article

Drug Name Select Trade
Levophed
Intropin
Accuneb, ProAir digihaler, Proair HFA, ProAir RespiClick, Proventil, Proventil HFA, Proventil Repetabs, Respirol , Ventolin, Ventolin HFA, Ventolin Syrup, Volmax, VoSpire ER
Elixophyllin, Quibron T, Quibron T/SR, Respbid, Slo-Bid, Slo-Phyllin, Theo X, Theo-24, Theo-Bid Duracap, TheoCap, Theochron, Theo-Dur, Theo-Dur Sprinkle , Theolair, Theolair SR, Theovent LA, T-Phyl, Uni-Dur, Uniphyl
Ermeza, Estre , Euthyrox, Levo-T, Levothroid, Levoxyl, Synthroid, Thyquidity, Thyro-Tabs, TIROSINT, TIROSINT-SOL, Unithroid
Cytomel, Triostat
Dilantin, Dilantin Infatabs, Dilantin-125, Phenytek
INBRIJA, Larodopa
Cafcit, NoDoz, Stay Awake, Vivarin
GOPRELTO, NUMBRINO
BuSpar, Buspar Dividose
Cymbalta, Drizalma, Irenka
Effexor, Effexor XR, Venlafaxine
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