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Mental Illness

Mental illnesses are medical conditions involving changes in behavior, thinking or emotions that interfere with a person’s ability to do daily tasks or care for themselves. Common mental health disorders include anxiety disorders and mood disorders such as depression, schizophrenia and ADHD. Other disorders include autism, borderline personality disorder, disassociate disorders, eating disorders and obsessive compulsive disorder, also known as OCD.

People diagnosed with serious mental illness typically need a combination of medication and talk therapy to get better.

More than 46 million Americans live with mental illness.

Mental illness isn’t the fault of the person diagnosed. It’s a medical problem, just like diabetes or heart disease, and it’s also common in the United States.

For some people, symptoms of poor mental health such as feeling lonely, being overwhelmed or worrying become more serious mental illnesses.

More than 46 million Americans live with mental illness, according to the National Institute of Mental Health. That’s about 1 in 5 Americans, and 1 in 24 has a serious illness.

The good news is that mental illness is highly treatable. For example, more than 80 percent of people with depression get better after treatment. As many as 90 percent of people with panic disorders get better, according to Mental Health America.

Anxiety Disorders

These disorders are marked by severe fear or dread associated with certain situations or objects. Patients have physical reactions to these objects and situations, including rapid heartbeat and sweating. They cannot control their responses. With anxiety disorders, these feelings do not go away and can get worse. They can interfere with things like job performance, school and relationships. These disorders include panic disorder, generalized anxiety disorder, phobias, obsessive-compulsive disorder and post-traumatic stress disorder, or PTSD.

Panic Disorder

Panic disorder is an anxiety disorder marked by panic attacks. Symptoms include fast heartbeat, chest pain, trouble breathing and dizziness. Patients with panic disorder often report intense feelings of terror or impending doom associated with attacks. These attacks can happen without warning. Fear of these attacks can control a person’s life, even making it difficult to leave the home.


Phobias are irrational fears. For example, acrophobia is fear of heights and agoraphobia is fear of public places. Some people have social phobia or phobias involving tunnels, highway driving, water, animals or flying. Phobias can be treated with medication and therapy.

Post-Traumatic Stress Disorder

This happens to some people who experience or witness a terrifying or traumatic event, such as a war, a bad accident or rape. PTSD is marked by flashbacks, feeling alone, sleep disturbances and angry outbursts. People with PTSD may have uncontrollable thoughts and intrusive memories about the event, and may avoid specific places, objects or events that bring about memories of the trauma. PTSD is treated with medications and psychotherapy. The therapist may pursue various treatment techniques.

Mood Disorders

These disorders involve changes in mood or disturbances. These typically involve depression or elation, also known as mania. These disorders are highly treatable. They include major depression and bipolar disorder.


More than 17 million Americans had at least one major depressive episode in 2018, according to the Substance Abuse and Mental Health Services Administration (SAMHSA). Symptoms persist and interfere with normal life.

Symptoms include:
  • Sadness
  • Loss of interest or pleasure in things the patient used to enjoy
  • Weight loss or gain
  • Sleeping troubles
  • Loss of energy
  • Feelings of worthlessness
  • Thoughts of death or suicide

Causes can be genetic, environmental or biochemical. Treatment options include antidepressant medications and talk therapy.

Bipolar Disorder

Formerly known as manic depression, bipolar disorder causes extreme emotional lows and highs in known as depression and mania. According to an article in JAMA, about 10 million adults and children in the U.S. have this condition.

While depression has symptoms of extreme sadness or worthlessness, mania manifests as extreme elation, jumpiness and overblown feelings of self-esteem.

A person will cycle back and forth between these moods. This cycling affects their ability to perform daily tasks. The length and severity of symptoms determines whether a person has bipolar I, bipolar II or cyclothymia.

People with bipolar I have severe symptoms of mania and depression. Those with bipolar II have more serious bouts of depression, but a lesser form of mania. People with cyclothymia have less severe symptoms of depression and mania, but symptoms are more chronic in nature.

Treating bipolar disorder can be tricky because traditional treatments for depression such as antidepressants can worsen symptoms of mania. The most effective treatment plans include atypical antipsychotics, mood stabilizers and psychotherapy.


Schizophrenia is a mental illness that affects a person’s emotions, behaviors, concentration and perception of reality. This disorder is rarer than depression or anxiety, but it can be crippling.

Symptoms of this disorder fall into three categories: positive, negative and cognitive.

Positive symptoms include movement disorders, hallucinations and delusions, or fixed false beliefs. Negative symptoms include reduced feelings of pleasure in life, reduced speaking and difficulty beginning activities. Cognitive symptoms include trouble paying attention, problems processing information and difficulty understanding information and using it.

The main treatments for schizophrenia are antipsychotics and psychotherapy. Coordinated specialty care combines psychotherapy, medication, case management education, family involvement and employment services to help people live better lives.


People with ADHD, or attention-deficit/hyperactivity disorder, have symptoms of inattention, hyperactivity and impulsivity. ADHD is usually diagnosed in children, but adults can also have the disorder.

Symptoms of ADHD include trouble staying organized, trouble focusing on tasks, restlessness, forgetfulness, excessive talking or difficulty paying attention to instructions and conversations.

People with ADHD may also have co-occurring disorders such as anxiety, depression or autism spectrum disorder.

For younger children, the first line of therapy should be behavior therapy, according to the American Academy of Pediatrics. This therapy teaches children how to control symptoms by changing behaviors. It focuses on positive reinforcement of “good” behaviors and improves social skills. Other types of therapy for ADHD are cognitive behavior therapy and parental skills training.

The typical medications for ADHD are called stimulants. These include drugs such as Adderall (amphetamine) and Ritalin (methylphenidate). But these should be used with caution because they are controlled substances and can be habit-forming.

Warning Signs of Mental Health Disorders

Major mental illness rarely appears without warning. In the early stages before a disorder is recognized, friends and family members may start to notice small changes. They may feel something is not right about their loved one’s thinking, feelings or behavior.

According to the American Psychiatric Association, warning signs may include:
  • Social withdrawal or loss of interest in others
  • Drop in functioning at school, work or social activities
  • Thinking problems, which can involve concentration, memory or logical thought and speech
  • Increased sensitivity to sights, sounds, smells or touch
  • Lack of initiative or interest for involvement in activities
  • Feeling disconnected from oneself or one’s surroundings
  • Illogical thinking, including exaggerated beliefs about personal abilities to understand meanings or influence events
  • Nervousness or fear or suspicion of others
  • Unusual or peculiar behavior
  • Sleep, appetite or mood changes

If a person displays several of these symptoms at once, and if the symptoms are interfering with the person’s life, he or she should visit a mental health professional.

Risks and Causes

A person’s character flaws are not causes of mental illness, and being “weak” or “lazy” has nothing to do with them, according to the U.S. National Library of Medicine. Researchers don’t know exactly what causes mental illness, but they think it is a combination of factors.

Risk factors and causes of mental illness include:
  • Alcohol or substance abuse
  • Chemical imbalances in the brain and other biological issues
  • Exposure to toxic chemicals or viruses in the womb
  • Genes and family history
  • Having cancer or other serious medical condition
  • Injury to the brain
  • Social isolation
  • Stress or a history of abuse and other negative life experiences, especially if they happen in childhood

Can Medication Cause Mental Illness?

While medications don’t typically cause mental illness, some drugs may cause psychiatric symptoms. This is especially true if a person suddenly develops psychiatric symptoms without a prior history.

Always tell your health care provider about all prescription, over-the-counter and illicit drugs you are taking.

Psychiatric Symptoms Potentially Caused by Medications
Agitation and Psychosis
Anabolic androgenic steroids, Benadryl and other antihistamines, prednisone and other corticosteroids, agitation decongestants, Zantac (ranitidine) and other H2 blockers, NSAIDs, opioids, proton pump inhibitors, fluoroquinolones, skeletal muscle relaxants
Anabolic androgenic steroids, prednisone and other corticosteroids, decongestants, ondansetron, penicillin, muscle relaxers, cyclosporine, acyclovir, didanosine, sumatriptan
Anabolic androgenic steroids, beta blockers, prednisone and other corticosteroids, Zantac (ranitidine) and other H2 blockers, statins, tetracyclines, digoxin, efavirenz, isotretinoin, NSAIDs, fluoroquinolones
Antibiotics, NSAIDs, anabolic androgenic steroids, ACE inhibitors, beta blockers, opioids, prednisone and other corticosteroids, Zantac (ranitidine) and other H2 blockers, centrally acting blood pressure medications such as methyldopa and reserpine, lidocaine
Zantac Side Effects
Rare cases of mental confusion, depression, agitation and hallucinations have been reported by patients taking Zantac. Read more about this drug's serious side effects.
View Side Effects

Treating Mental Illness

Most mental illness can be treated in an effective way, especially with early diagnosis. Treatment options include psychotherapy, medication and learning skills to manage symptoms.

With effective treatment, people with mental illness can live better, productive lives. Treatment plans are tailored to the individual patient, because people react to therapy and medication differently.


Also called talk therapy, psychotherapy is the best option for some patients. There are a number of psychotherapy techniques to help patients identify and modify thoughts, behavior and emotions with the help of a trained and licensed professional.

The two most popular forms of psychotherapy are psychodynamic therapy and cognitive behavioral therapy, according to Harvard Medical School.

Psychodynamic Therapy

Psychodynamic therapy focuses on how current and past relationships, life events and desires affect the choices you make and how you feel. The theory is that people create thought patterns and behaviors to protect themselves from traumatic experiences or external threats. A therapist can help people identify these thought patterns and behaviors and help develop strategies to cope with and overcome them.

For example, someone with overbearing parents may have difficulty developing intimate relationships because they are afraid of being controlled.

This type of therapy can also help improve social interaction. A type of psychodynamic therapy called interpersonal therapy blends psychodynamic and cognitive behavior therapy to help people deal with relationships and teach better ways to communicate with others.

Cognitive Behavior Therapy (CBT)

In contrast to psychodynamic therapy, cognitive behavior therapy (CBT) focuses less on feelings. Instead, it teaches people how to recognize behavior and thought patterns that are causing problems. Then, it teaches techniques to change these patterns. The theory is that people can change feelings by changing thoughts and actions.

People have used CBT to treat smoking, phobias, procrastination and help symptoms of depression and anxiety.

For example, people may have distorted thinking patterns such as always thinking the worst, excessive guilt or self-criticism or thinking people view them negatively. CBT therapists help people recognize these patterns and change them.

CBT helps people develop more positive and productive responses to distress such as breathing deeply to relax instead of hyperventilating during stressful situations.

Need help finding a therapist?
The National Alliance on Mental Illness has information on different types of therapists and how to find one. Call the NAMI helpline at 800-950-NAMI or text “NAMI” to 741741 for help in a crisis.

Prescription Drugs

There are a number of prescription drugs to treat mental illness. According to a 2017 research letter published in the journal JAMA Internal Medicine, one in six Americans took a psychiatric medicine in 2013.

Often, health care providers will use medication as the first line of therapy for mental illness. But people should ask their health care providers if psychotherapy might be effective enough without medication.

Depending on the type of mental illness, health care providers may prescribe a specific type of drug. Because people respond to medications differently, finding the proper medication and dosage is often a trial-and-error process. Sometimes a health care provider may prescribe more than one medication.

It’s important for people to be patient and communicate their feelings and if they have experience side effects to their health care provider. Each drug has its own side effects and the patient and health care provider need to weight the risks and benefits of each medication.

Some medications for mental illness can be habit-forming. These include stimulants and benzodiazepines. Benzodiazepines are considered problematic for long-term use and are no longer recommended as the first line of treatment for anxiety.

Medications for Depression and Anxiety

Medications for anxiety and depression are similar. These drugs are designed to balance some of the natural chemicals in the brain. Classes of antidepressants include selective serotonin reuptake inhibitors, monoamine oxidase inhibitors, atypical antidepressants and tricyclic antidepressants. SSRIs are the most popular type. They work by increasing the level of serotonin in the brain. Serotonin plays a role in mood.

Common Medications for Depression and Anxiety
Drug Class Name (generic)
Atypical Antidepressants Desyrel (trazodone), Serzone (nefazodone), Wellbutrin (bupropion)
Benzodiazepines (no longer recommended as first choice for treatment of anxiety) Xanax (alprazolam), Klonopin (clonazepam), Valium (diazepam), Ativan (lorazepam)
Monoamine Oxidase Inhibitors (MAOIs) (recommended for depression, not anxiety) Emsam skin patch (selegiline), Parnate (tranylcypromine), Marplan (isocarboxzaid)
Selective Serotonin Reuptake Inhibitors (SSRI) Celexa (citalopram), Lexapro (escitalopram), Paxil (paroxetine), Prozac (fluoxetine), Trintellix (vortioxetine), Viibryd (vilazodone), Zoloft (sertraline)
Serotonin and Norepinephrine Reuptake Inhibitors (SNRI) Cymbalta (duloxetine), Effexor (venlafaxine), Fetzima (levomilnacipran), Pristiq (desvenlafaxine)
Tricyclic and Tetracyclic Antidepressants Ascendin (amoxapine), Elavil (amitriptyline), Ludiomil (maprotiline)

Medications for Bipolar Disorder and Schizophrenia

Medications for bipolar and schizophrenia are called antipsychotics. Antipsychotics are used to treat conditions that involve psychosis. Psychosis involves a disconnection with reality. These drugs relieve symptoms but are not cures.

Older antipsychotics are referred to as typical antipsychotics or neuroleptics. Newer antipsychotics are called atypical antipsychotics.

Both types of antipsychotics work to treat symptoms of schizophrenia and mania. Long-term use of older antipsychotics may cause a potentially incurable nerve condition called tardive dyskinesia. This condition involves uncontrolled muscle movements, often around the mouth.

Drugs called mood stabilizers are used to treat bipolar disorders and mood swings. Lithium is a well-known mood stabilizer. The U.S. Food and Drug Administration has approved it for treatment of mania and bipolar disorder. Mood stabilizers work by decreasing abnormal activity in the brain.

Atypical Antipsychotics for Bipolar Disorder or Schizophrenia
Risperdal Side Effect Information
Risperdal caused a host of common side effects in clinical trials, including increased appetite, upper respiratory tract infection, vomiting and rash. Learn more about Risperdal's side effects.
View Side Effects
Typical Antipsychotics for Schizophrenia
  • Thorazine (chlorpromazine)
  • Proxlixin (fluphenazine)
  • Haldol (haloperidol)
  • Loxitane (oxapine)
  • Trilafon (perphenazine)
  • Navane (thiothixene)
  • Stelazine (trifluoperazine)
Mood Stabilizers for Bipolar Disorder

Safely Using Psychiatric Medications

Experts advise that doctors should prescribe these medications at the lowest effective dose. They should continue to monitor their patients to determine whether the drugs are still needed. Researchers have found many patients are given long-term prescriptions for drugs that are recommended only for short-term use. Doctors and patients should work together on safely discontinuing drugs. Suddenly halting a psychiatric drug can be dangerous.

Prescription psychiatric drugs should be given at the lowest dose that will be effective.

Patients should also discuss possible interactions with other medications and supplements, as well as food. They should avoid mixing prescription drugs with alcohol and other substances.

Sometimes, a doctor may prescribe a medication for a use other than what is approved by the FDA. This is known as off-label prescribing. Patients should inquire if their drugs are being given for approved uses. If not, the doctor and patient should be clear about the limits of the research supporting the prescription in the patient’s circumstances.

Also, when patients take generic medications, they should realize they are not exactly the same as the name-brand drug. They may have different inactive ingredients, such as fillers and binders. However, generic drugs are required to have the same active ingredient, strength, route of administration and dosage form as name-brand drugs, and must be manufactured under the same strict standards.

Side Effects from Drugs to Treat Mental Illness

Medications used to treat mental illness are linked to a number of unpleasant side effects. They can make it difficult for patients to maintain employment or stay in school. Expected side effects vary depending on the class of medication used.

Common side effects include:
  • Sleepiness
  • Nightmares
  • Dizziness
  • Drowsiness
  • Dry mouth
  • Nervousness
  • Headaches
  • Shakiness
  • Confusion
  • Weight gain
  • Nausea, diarrhea or stomach upset
  • Sexual problems

Other Treatments

In addition to prescription drugs, patients have the option of exploring other kinds of treatments. These include brain stimulation and complementary or alternative medicine.

Examples of complementary treatments suggested by the National Alliance on Mental Illness include herbs and supplements and exercise, including yoga. These treatments may be helpful, but NAMI stresses that the FDA does not review or approve many of these treatments.

The government agency that oversees these therapies is the National Center for Complementary and Integrative Health. People can visit this website to see what the current science says about the effectiveness for a particular complementary therapy.

Brain Stimulation

Brain stimulation involves using electricity to directly activate or inhibit brain activity. This can involve electrodes implanted in the brain or placed on the scalp. Magnetic fields can also be applied to the head.

These therapies can be helpful for patients who have mental disorders that don’t respond to other kinds of treatment. The most commonly used of these is electroconvulsive therapy or ECT — once called electroshock therapy. ECT is used to treat severe depression that has not responded to other therapy. It also may be useful in cases of bipolar disorder or schizophrenia. ECT involves the use of electrodes placed on the head of a patient under anesthesia. They pass electric current through the brain.

Research has found that ECT shows results more quickly than other forms of treatment.

Herbs and Supplements

Various herbs and supplements are used to treat different mental health conditions. For example, omega-3 fatty acids may help decrease the risk of developing chronic schizophrenia in young people who have had a psychotic episode. Folic acid or vitamin B9 may be useful in the treatment of depression and schizophrenia.

Exercise, Yoga and Meditation

Exercise can relieve mental illness and reduce some side effects from psychiatric medications.

Mind and body treatment options include yoga, exercise, meditation and Tai chi. These activities can improve mood and relieve anxiety and other symptoms of mental illness.

Exercise can also reduce side effects of many conventional psychiatric medicines, such as weight gain and fatigue. Research has found evidence that these activities may reduce symptoms of depression and anxiety.

Experts theorize that yoga, for example, may affect brain chemicals called neurotransmitters, boosting levels of chemicals like serotonin that make people feel good. The exercise may also reduce inflammation and have a positive effect on lipids in the body.

Meditation involves sitting in a quiet place, focusing on breathing or a specially chosen word, and letting distractions come and go without judgment. According to the National Center for Complementary and Integrative Medicine, some research suggests that meditation may reduce symptoms of anxiety, depression and insomnia.

Please seek the advice of a medical professional before making health care decisions.

Michelle Llamas, Senior Content Writer
Written By Michelle Llamas Senior Writer

Michelle Llamas has been writing articles and producing podcasts about drugs, medical devices and the FDA for nearly a decade. She focuses on various medical conditions, health policy, COVID-19, LGBTQ health, mental health and women’s health issues. Michelle collaborates with experts, including board-certified doctors, patients and advocates, to provide trusted health information to the public. Some of her qualifications include:

  • Member of American Medical Writers Association (AMWA) and former Engage Committee and Membership Committee member
  • Centers for Disease Control and Prevention (CDC) Health Literacy certificates
  • Original works published or cited in The Lancet, British Journal of Clinical Pharmacology and the Journal for Palliative Medicine
Edited By

50 Cited Research Articles writers follow rigorous sourcing guidelines and cite only trustworthy sources of information, including peer-reviewed journals, court records, academic organizations, highly regarded nonprofit organizations, government reports and interviews with qualified experts. Review our editorial policy to learn more about our process for producing accurate, current and balanced content.

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