- Panic attack facts
- What are panic attacks?
- Are panic attacks serious?
- What are causes and risk factors for panic attacks?
- What are panic attack symptoms and signs in adults, teens, and children?
- How do health-care professionals diagnose panic disorder? What types of doctors treat this condition?
- What is the treatment for panic attacks? What medications treat panic attacks?
- What are complications of untreated panic attacks?
- What is the prognosis for panic disorder?
- Is it possible to prevent panic attacks?
"All of a sudden, I felt a tremendous wave of fear for no reason at all. My heart was pounding, my chest hurt, and it was getting harder to breathe. I thought I was going to die."
"I'm so afraid. Every time I start to go out, I get that awful feeling in the pit of my stomach, and I'm terrified that another panic attack is coming or that some other, unknown terrible thing was going to happen."
Panic attack facts
- Symptoms of panic attacks usually begin abruptly and include
- rapid heartbeat,
- unpleasant chest sensations,
- shortness of breath,
- stomach upset,
- tingling, and
- severe anxiousness.
- While panic disorder can certainly be serious, it is not immediately physically threatening.
- A variety of treatments are available, including several effective medications, and specific forms of psychotherapy.
- People who have panic attacks can use a number of lifestyle changes like aerobic exercise, avoiding triggers like alcohol, caffeine, and illicit drugs, as well as stress-management techniques to help decrease anxiety.
What are panic attacks?
The above statements are two examples of what a panic attack might feel like. Panic attacks may be symptoms of an anxiety disorder. Historically, panic has been described in ancient civilizations, as with the reaction of the subjects of Ramses II to his death in 1213 BC in Egypt, and in Greek mythology as the reaction that people had to seeing Pan, the half man, half goat god of flocks and shepherds. In medieval then Renaissance Europe, severe anxiety was grouped with depression in descriptions of what was then called melancholia. During the 19th century, panic symptoms began to be described as neurosis, and eventually the word panic began being used in psychiatry.
These episodes are a serious health problem in the U.S. At least 20% of adult Americans, or about 60 million people, will suffer from panic at some point in their lives. About 1.7% of adult Americans, or about 3 million people, will have full-blown panic disorder at some time in their lives, women twice as often as men. The most common age at which people have their first panic attack (onset) is between 15 and 19 years of age. Panic attacks are significantly different from other types of anxiety, in that panic attacks are very sudden and often unexpected, appear to be unprovoked, and are often disabling.
Childhood panic disorder facts include that about 0.7% of children suffer from panic disorder or generalized anxiety disorder, half as often as occurs in adolescents. While panic is found to occur twice as often in women compared to men, boys and girls tend to develop this condition at equal frequency.
Once an individual has had a panic attack, for example, while driving, shopping in a crowded store, or riding in an elevator, he or she may develop irrational fears, called phobias, about these situations and begin to avoid them. Eventually, the avoidance and level of nervousness about the possibility of having another attack may reach the point at which the mere idea of engaging in the activities that preceded the first panic attack triggers future panic attacks, resulting in the person with panic disorder potentially being unable to drive or even step out of the house (agoraphobia). Thus, there are two types of panic disorder, panic disorder with or without agoraphobia. Like other mental-health conditions, panic disorder can have a serious impact on a person's daily life unless the individual receives effective treatment.
Panic attacks in children may cause the child's grades to decline, their avoiding school and other separations from parents, as well as possibly experiencing substance abuse, depression, or suicidal thoughts, plans, and/or actions.
Are panic attacks serious?
Yes, panic attacks are real and potentially quite emotionally disabling. Fortunately, they can be controlled with specific treatments. Because of the disturbing physical signs and symptoms that accompany panic attacks, they may be mistaken for heart attacks or some other life-threatening medical problem. In fact, up to 25% of people who visit emergency rooms because of chest pain are actually experiencing panic. This can lead to people with this symptom often undergoing extensive medical testing to rule out physical conditions. Sadly, sometimes more than 90% of these individuals are not appropriately diagnosed as suffering from panic.
Loved ones, as well as medical personnel, generally attempt to reassure the panic attack sufferer that he or she is not in great danger. However, these efforts at reassurance can sometimes add to the patient's struggles. If the doctors say things like, "it's nothing serious," "it's all in your head," or "nothing to worry about," this may give the false impression that there is no real problem, they should be able to overcome their symptoms without help, and that treatment is not possible or necessary. More accurately, while panic attacks can undoubtedly be serious, they are not organ-threatening. Therefore, for people who might wonder what to do to help the panic sufferer at the time of an anxiety attack, a more effective approach tends to be acknowledge their fear and the intensity of their symptoms while reassuring the person having the panic attack that what is occurring is not life-threatening and can be treated.
What are causes and risk factors for panic attacks?
Although there are not specific causes for panic attacks in adults, teens, or children, like most other emotional symptoms, panic is understood to be the result of a combination of biological vulnerabilities, ways of thinking, and environmental factors like social stressors. According to one theory of panic disorder, the body's normal "alarm system," the set of mental and physical mechanisms that allows a person to respond to a threat, tends to be triggered when there is no danger. Scientists don't know specifically why this happens or why some people are more susceptible to the problem than others. Panic disorder has been found to run in families, and this may mean that inheritance (genetics) plays a role in determining who will develop the condition. However, many people who have no family history of the disorder develop it. Studies differ as to whether drugs like marijuana or nutritional deficiencies like zinc or magnesium deficiencies may also be risk factors for developing panic disorder.
Poverty and low education level tend to be associated with anxiety, but it is unclear if those factors cause or are caused by anxiety. While some statistics suggest that disadvantaged ethnic minorities tend to suffer from internalizing disorders like panic disorder less often than the majority population in the United States, other research shows that may be the result of differences in how ethnic groups interpret and discuss signs and symptoms of intense fright, like panic attacks. Difficulties the examiner may have in appropriately recognizing and understanding ethnic differences in symptom expression is also thought to play a role in ethnic differences in the reported frequency of panic and other internalizing disorders.
Psychologically, people who develop panic attacks or another anxiety disorder are more likely to have a history of what is called anxiety sensitivity. Anxiety sensitivity is the tendency for a person to fear that anxiety-related bodily sensations (like brief chest pain or stomach upset) have dire personal consequences (for example, believing that it automatically means their heart will stop or they will throw up, respectively). From a social standpoint, a risk factor for developing panic disorder as an adolescent or adult is a history of being physically or sexually abused as a child. This is even more the case for panic disorder when compared to other anxiety disorders. Often, the first attacks are triggered by physical illnesses, another major life stress, or perhaps medications that increase activity in the part of the brain involved in fear reactions.
What are panic attack symptoms and signs in adults, teens, and children?
As described in the first example above, the symptoms of a panic attack develop suddenly, without any apparent cause. They may include physical and emotional symptoms like
- racing or pounding heartbeat (palpitations);
- chest pains;
- stomach upset;
- dizziness, lightheadedness, nausea;
- difficulty breathing, a sense of feeling smothered;
- a choking sensation;
- hand tingling or numbness;
- hot flashes/sweating or cold flashes/chills;
- trembling and shaking;
- dreamlike sensations or perceptual distortions like a feeling of detachment;
- terror, a sense that something unimaginably terrible is about to occur and one is powerless to prevent it;
- a need to escape;
- worrying about not knowing how to control their symptoms, leading to them doing something embarrassing;
- fear of dying.
Although how long a panic attack lasts can vary greatly, its duration is typically more than 10 minutes. A panic is one of the most distressing conditions that a person can endure, and its symptoms can closely mimic those of a heart attack. Typically, most people who have one panic attack will have others, and when someone has repeated attacks with no other apparent physical or emotional cause and it negatively changes their behavior due to the attacks or feels severe anxiety about having another attack, he or she is said to have panic disorder. A number of other emotional problems can have panic attacks as a symptom. Some of these illnesses include posttraumatic stress disorder (PTSD), schizophrenia, and intoxication or withdrawal from alcohol and certain other drugs of abuse.
Some medical conditions, like thyroid abnormalities and anemia, as well as certain medications, can produce severe anxiety. Examples of such medications include stimulants like methylphenidate (Ritalin) or amphetamine salts (Adderall), diabetes medications like metformin (Glucophage) and insulin, antimalarial medications like quinine, as well as corticosteroid withdrawal, such as withdrawal from dexamethasone (Decadron). As individuals with panic disorder seem to be at higher risk of having a heart valve abnormality called mitral valve prolapse (MVP), this possibility should be investigated by a doctor since MVP may dictate the need for special precautions when the individual is being treated for any dental problem. While the development of panic attacks have been attributed to the use of food additives like aspartame, alone or in combination with food dyes, more research is needed to better understand the role such substances may have on this disorder.
Anxiety attacks that occur while sleeping, also called nocturnal panic attacks, occur less often than panic attacks during the daytime but affect about 40%-70% of those who suffer from daytime panic attacks. This symptom is also important because people who suffer from panic symptoms during sleep tend to have more respiratory distress associated with their panic. They also tend to experience more symptoms of depression and other psychiatric disorders compared to people who do not have panic attacks at night. Nocturnal panic attacks tend to cause sufferers to wake suddenly from sleep in a state of sudden fear or dread for no apparent reason. In contrast to people with sleep apnea and other sleep disorders, sufferers of nocturnal panic can have all the other symptoms of a panic attack. The duration of nocturnal panic attacks tends to be less than 10 minutes, but it can take much longer to fully calm down for those who experience them.
While panic disorder in adolescents tends to have similar symptoms as in adults, symptoms of this condition in younger children are less likely to include the thought-based or so-called cognitive aspects. Specifically, teenagers are more likely to feel unreal or as if they are functioning in a dream-like state (derealization) or be frightened of going crazy or of dying.
Symptoms of panic attacks in women tend to include more avoidance of anxiety-provoking situations, more frequent recurrence, and more often result in the use of medical care compared to panic attack symptoms in men. The frequency of panic attacks may increase, decrease, or remain unchanged during pregnancy.
How do health-care professionals diagnose panic disorder? What types of doctors treat this condition?
A variety of medical and mental-health professionals are qualified to assess and treat panic disorders. From purely medical professionals like primary-care doctors, emergency-room physicians to practitioners with mental-health training like psychiatrists, psychologists and social workers, a variety of health-care providers may be involved in the care of panic disorder sufferers. Some practitioners will administer a self-test of screening questions to people whom they suspect may be suffering from panic disorder. In addition to looking for symptoms of repeated panic attacks by asking detailed questions about the sufferer's history and conducting a mental-status examination, mental-health professionals will explore the possibility that the individual's symptoms are caused by another emotional illness instead of, or in addition to the diagnosis of panic disorder. For example, people with an addiction often experience panic attacks, but those symptom characteristics generally only occur when the person is either intoxicated or withdrawing from the substance. The practitioner will also likely ensure that a physical examination and any other appropriate medical tests have been done recently to explore whether there is any medical problem that could be contributing to the occurrence of panic attacks. That is particularly important since many medical conditions may have panic attacks as a symptom and therefore require that the underlying medical condition be treated in order to alleviate the associated anxiety. Examples of that include the need for treatment with antibiotics for infections like Lyme disease or vitamin supplements to address certain forms of anemia.
What is the treatment for panic attacks? What medications treat panic attacks?
As the result of years of research, there are a variety of treatments available to help people who suffer from panic attacks learn how to control the symptoms. This includes several effective medical treatments, and specific forms of psychotherapy. In terms of medications, specific members of the selective serotonin reuptake inhibitor (SSRI), the selective serotonin and norepinephrine reuptake inhibitors (SSNRI), and the benzodiazepine families of medications are approved by the U.S. Food and Drug Administration (FDA) for effective treatment of panic disorder. Examples of such medications include fluoxetine (Prozac), sertraline (Zoloft), paroxetine (Paxil), escitalopram (Lexapro), citalopram (Celexa), vortioxetine (Brintellix), and vilazodone (Viibryd) from the SSRI group, duloxetine (Cymbalta), venlafaxine (Effexor), desvenlafaxine (Pristiq), and levomilnacipran (Fetzima) from the SSNRI group, and clonazepam (Klonopin) and lorazepam (Ativan) from the benzodiazepine group. Although alprazolam (Xanax) is often used to treat panic attacks, its short duration of action can sometimes result in having to take it several times per day. Medications from the beta-blocker family (for example, propranolol [Inderal]) are sometimes used to treat the physical symptoms, like racing heart rate associated with a panic attack. Some individuals who suffer from severe panic attacks may benefit from treatment with gabapentin (Neurontin), which was initially found to treat seizures, or benefit from a neuroleptic medication like risperidone (Risperdal), olanzapine (Zyprexa), quetiapine (Seroquel), aripiprazole (Abilify), paliperidone (Invega), asenapine (Saphris), iloperidone (Fanapt), or lurasidone (Latuda).
Before SSRIs and SSNRIs became available, medications from the group known as the tricyclic antidepressants (TCAs) were often used to address panic disorder. Although TCAs have been found to be equally effective in treating panic attacks, SSRIs and SSNRIs have been proven to be safer and better tolerated. Therefore TCAs are used much less often than they were previously.
When used in the appropriate person with close monitoring, medications can be quite effective as part of treatment for panic disorder. However, as anything that is ingested carries a risk of side effects, it is important for the individual who has panic attacks to work closely with the prescribing health-care professional to decide whether treatment with medications is an appropriate intervention and, if so, which medication should be administered. The person being treated should be closely monitored for the possibility of side effects that can vary from minor to severe, and in some cases, even be life-threatening. Due to the possible risks to the fetus of a mother being treated for panic attacks with medication, psychotherapy should be the first treatment tried when possible during pregnancy and the risk of medication treatment should be weighed against the risk of continued panic attacks in regards to the impact of a developing fetus.
For people who may be wondering how to avoid panic attacks using treatment without prescribed medication, natural remedies may be an option. While herbal supplements that contain kava have been found to be helpful for some people with mild to moderate panic disorder, the research data is still considered to be too limited for many physicians to recommend treatment with other natural remedies like valerian or passionflower. Also, care should be taken when taking any dietary supplements, since supplements are not regulated in terms of quality, content, or effectiveness.
The psychotherapy component of treatment for panic disorder is at least as important as medication. In fact, research shows that psychotherapy alone or the combination of medication and psychotherapy treatment are more effective than medication alone in the long-term management of panic attacks. In overcoming anxiety, cognitive behavioral therapy is widely accepted as an effective form of psychotherapy treatment, for both adults and children. This form of psychotherapy seeks to help those with panic disorder identify and decrease the irrational thoughts and behaviors that reinforce panic symptoms and can be done either individually, in group therapy, in partner-assisted therapy, and even over the Internet. Behavioral techniques that are often used to decrease anxiety include relaxation techniques (like breathing techniques or guided imagery) and gradually increasing exposure to situations that may have previously triggered anxiety in the panic disorder sufferer. Helping the person with anxiety understand how to handle the emotional forces that may have contributed to developing symptoms (panic-focused psychodynamic psychotherapy) has also been found to be effective in teaching an individual with panic disorder how to prevent an anxiety attack or how to calm down in order to decrease or stop a panic attack once it starts.
There are also things that people with panic disorder can do to learn how to handle it and to make treatment more effective. Since substances like drinking alcohol or caffeinated beverages, or using illicit drugs can worsen panic attacks, those things should be avoided. Other tips to prevent or manage panic attacks include engaging in aerobic exercise and stress-management techniques like deep breathing, massage therapy, and yoga, since these self-help activities have also been found to help decrease the frequency and severity of panic attacks. Although many people use home remedies like breathing into a paper bag when afflicted by the hyperventilation that can be associated with panic, the benefit received may be the result of the individual believing it will remedy the symptoms (placebo effect). Also, breathing into a paper bag when one is already having trouble breathing can make matters worse when the hyperventilation is the result of conditions of oxygen deprivation, like an asthma attack or a heart attack.
People with panic disorder may also need treatment for other emotional problems. Depression has often been associated with panic disorder, as have alcohol and drug abuse. Fortunately, with proper treatment, these problems associated with panic disorder can be overcome effectively, just like panic disorder itself.
Sadly, many people with panic attacks do not seek or receive appropriate treatment.
What are complications of untreated panic attacks?
Without treatment, panic attacks tend to occur repeatedly for months or years. While they typically begin in young adulthood, the symptoms may arise earlier or later in life in some people. Complications, which are symptoms that can develop as a result of continued panic attacks and develop into other mental illnesses, may include specific irrational fears (phobias), especially of leaving home (agoraphobia) and avoidance of social situations. Other possible complications can include depression, work or school problems, suicidal thoughts or actions, financial problems, and alcohol or other substance abuse. Panic disorder also predisposes sufferers to developing heart disease and of dying prematurely.
If left untreated, anxiety may worsen to the point at which the person's life is seriously affected by panic attacks and by attempts to avoid or conceal them. In fact, many people have had problems with friends and family, failed in school, and/or lost jobs while struggling to cope with this condition. There may be periods of spontaneous improvement in the episodes, but panic attacks do not usually go away unless the person receives treatments designed specifically to help people with these symptoms.
What is the prognosis for panic disorder?
Often, a combination of psychotherapy and medications produces good results in the treatment of panic disorder. Improvement is usually noticed in about two to three months. Thus, appropriate treatment for panic disorder can prevent panic attacks or at least substantially reduce their severity and frequency, bringing significant relief to 70%-90% of people with the illness. More than 18% of people who are assessed but not treated for this condition tend to relapse in less than two years.
American Academy of Child & Adolescent Psychiatry. "Facts for Families: Panic Disorder in Children and Adolescents." 50 Nov. 2004.
American Psychiatric Association. Diagnostic and Statistical Manual of Mental Disorders DSM-IV-TR. 4th ed. Washington, D.C.: 2000.
American Psychiatric Association. Practice Guidelines for the Treatment of Patients With Panic Disorder. 2nd ed. Arlington, VA: 2009.
Beesdo, K., S. Knappe, and D.S. Pine. "Anxiety and anxiety disorders in children and adolescents: Developmental issues and implications for DSM-V." Psychiatric Clinics of North America 32.3 Sept. 2009: 483-524.
Breslau, J., S. Aguilar-Gaxiola, K.S. Kendler, M. Su, et al. "Specifying Race-Ethnic Differences in Risk for Psychiatric Disorder in a U.S. National Sample." Psychological Medicine 36.1 Jan. 2006: 57-68.
Busch, F.N. and B.L. Milrod. "Panic-Focused Psychodynamic Psychotherapy." Psychiatric Times 25.2 Feb. 1, 2008.
Campbell, S.G., and A.A. Abbass. "Chest Pain -- Consider Panic Disorder." Canadian Family Physician 53.5 May 2007: 807-808.
Dannon, P.N., I. Iancu, K. Lowengrub, L. Grunhaus, and M. Kotler. "Recurrence of Panic Disorder During Pregnancy: A 7-Year Naturalistic Follow-up Study." Clinical Neuropharmacology 29.3 May-June 2006: 132-137.
Dannon, P.N., and K. Lowengrub. "Panic Disorder and Pregnancy: Challenges of Caring for Mother and Child." Psychiatric Times 25.3 Mar. 2006.
David, J.E., S.H. Yale, and H.J. Vidaillet. "Hyperventilation-Induced Syncope: No Need to Panic." Clinical Medicine and Research 1.2 (2003): 137-139.
Friedlander, A.H., S.R. Marder, E.C. Sung, and J.S. Child. "Panic Disorder: Psychopathology, Medical Management and Dental Implications." The Journal of the American Dental Association 135.6 (2004): 771-778.
Furukawa, T.A., and N. Watanabe. "Psychotherapy Plus Antidepressant for Panic Disorder With or Without Agoraphobia." The British Journal of Psychiatry 188 (2006): 305-312.
Garakani, A., and A.G. Mitton. "New-onset panic, depression and suicidal thoughts, and somatic symptoms in a patient with a history of Lyme Disease." Case Reports in Psychiatry 2015.
Gomez-Caminero, A., W.A. Blumentals, L.J. Russo, R.R. Brown, and R. Castilla-Puentes. "Does Panic Disorder Increase the Risk of Coronary Heart Disease? A Cohort Study of a National Managed Care Database." Psychosomatic Medicine 67 (2005): 688-691.
Goodwin, R.D., R. Lieb, M. Hoefler, H. Pfister, et al. "Panic Attack as a Risk Factor for Severe Psychopathology." American Journal of Psychiatry 161 Dec. 2004: 2207-2214.
Ham, P., D.B. Waters, and M.N. Oliver. "Treatment of Panic Disorder." American Family Physician 71.4 Feb. 15, 2005.
Johnson, M.R., A.G. Hartzema, T.L. Mills, J.M. De Leon, M. Yang, C. Frueh, and A. Santos. "Ethnic Differences in the Reliability and Validity of a Panic Disorder Screen." Ethnic Health 12.3 June 2007: 283-296.
Katon, W.J. "Panic Disorder." The New England Journal of Medicine 354 June 2006: 2360-2367.
Kelly, C.M., A.F. Jorm, and B.A. Kitchener. "Development of Mental Health First Aid Guidelines for Panic Attacks: a Delphi Study." Biomedical Central Psychiatry 9 (2009): 49.
Kessler, R.C., W. Tat-Chiu, R. Jin, A. Meron-Ruscio, et al. "The Epidemiology of Panic Attacks, Panic Disorder and Agoraphobia in the National Comorbidity Survey Replication." Archives of General Psychiatry 63 (2006): 415-424.
Lau, K., W.G. McLean, D.P. Williams, and C.V. Howard. "Synergistic Interactions Between Commonly Used Food Additives in a Developmental Neurotoxicity Test." Toxicological Sciences 90.1 2006: 178-187.
Madaan, V. "Assessment of Panic Disorder Across the Life Span." Focus 6 Fall 2008: 438-444.
Marchesi, C. "Pharmacological Management of Panic Disorder." Neuropsychiatric Disorders Treatment 4.1 Feb. 2008: 93-106.
Merikangas, K.R., J.P. He, D. Brody, P.W. Fisher, K. Bourdon, and D.S. Koretz. "Prevalence and Treatment of Mental Disorders Among US Children in the 2001–2004 NHANES." Pediatrics 125 Jan. 2010: 75-81.
Nardi, A.E. "Some notes on a historical perspective of panic disorder." Journal of Brazilian Psychiatry (J Brasil Psiquiatr) 55.2 (2006): 154-160.
National Institute of Mental Health of the U.S. Department of Health and Human Services
Pande, A.C., M.H. Pollack, J. Crockatt, M. Greiner, G. Chouinard, et al. "Placebo-Controlled Study of Gabapentin Treatment of Panic Disorder." Journal of Clinical Psychopharmacology 20.4 Aug. 2000: 467-471.
Pincus, D.B., J.E. May, S.W. Whitton, S.G. Mattis, and D.H. Barlow. "Cognitive-Behavioral Treatment of Panic Disorder in Adolescence." Journal of Clinical Child and Adolescent Psychology 39.5 Sept. 2010: 638-49.
Pollack, M.H., et al. "Panic: Course, Complications and Treatment of Panic Disorder." Journal of Psychopharmacology 14.2.1 (2000): S25-30.
Rubinchik, S.M., A.S. Kablinger, and J.S. Gardner. "Medications for Panic Disorder and Generalized Anxiety Disorder During Pregnancy." Journal of Clinical Psychiatry 7.3 (2005): 100-105.
Saeed, S.A., R.M. Bloch, and D.J. Antonacci. "Herbal and Dietary Supplements for Treatment of Anxiety Disorders." American Family Physician 76 Aug. 2007: 549-556.
Safren, S.A., B.S. Gershuny, P. Marzol, M. Otto, and M.H. Pollack. "History of Childhood Abuse in Panic Disorder, Social Phobia and Generalized Anxiety Disorder." The Journal of Nervous and Mental Disease 190.7 July 2002: 453-456.
Sarisoy, G., O. Boke, A.C. Arik, and A.R. Sahin. "Panic Disorder With Nocturnal Panic Attacks: Symptoms and Comorbidities." European Psychiatry 23.3 Apr. 2008: 195-200.
Stores, G. "Clinical Diagnosis and Misdiagnosis of Sleep Disorders." Journal of Neurological Neurosurgical Psychiatry 78 (2007): 1293-1297.
Taborska, V. "Incidence of Latent Tetany in Patients With Panic Disorder." Cesk Psychiatry 91.3 July 1995: 183-190.
Wang, T., et al. "Adverse effects of medical cannabinoids: a systematic review." Canadian Medical Association Journal 178.13 June 2008: 1669-1678.
White, K.S., L.A. Payne, J.M. Gorman, et al. "Does maintenance CBT contribute to long-term treatment response of panic disorder with or without agoraphobia? A randomized controlled clinical trial." Journal of Consulting and Clinical Psychology 81.1 Feb. 2013: 47-57.
Yonkers, K.A., C. Zlotnick, and J. Allsworth, et al. "Is the Course of Panic Disorder the Same in Women and Men?" American Journal of Psychiatry 155 May 1998: 596-602.
Zabun, N., M.A.K. Azad, A. Rahman, M. Arifur, et al. "Comparative Analysis of Serum Manganese, Zinc, Calcium, Copper and Magnesium Level in Panic Disorder Patients." Biological Trace Element Research July 2009.
Zvolensky, M.J., and N.B. Schmidt. "Introduction to Anxiety Sensitivity." Behavior Modification 31.2 (2007): 139-144.