Signs of Mental Illness

Medically Reviewed by Smitha Bhandari, MD on April 01, 2022
3 min read

Everyone goes through changes in their emotions, thoughts, and behavior from time to time. But when these changes make you less able to function day to day, they may be signs of a mental illness.

Mental illness takes many forms, including depression, anxiety disorders, bipolar disorder, and schizophrenia. It's common, affecting some 44 million Americans each year.

There's no simple test to tell you whether you or someone you know has a mental illness. Often, you or people around you will notice small changes in how you act long before the symptoms seriously affect you.

If you recognize when something seems amiss, you can talk to a doctor or mental health professional about what to do. Getting help, early on, often keeps mental illness from getting worse.

Certain symptoms could be a sign that it’s time to seek help, especially if you notice more than a couple. They include:

  • Sadness or crankiness that lasts longer than usual
  • Withdrawal from friends and family
  • Loss of interest in things you used to enjoy
  • High and low extremes of emotion
  • Big changes in sleeping or eating habits
  • Worries or fears that seem out of proportion
  • Ignoring personal grooming and hygiene
  • Changes in your sex drive
  • Disorganized or confused thoughts
  • Excessive anger
  • Drug or alcohol abuse
  • Many unexplained physical illnesses
  • Ideas that don’t line up with reality
  • Seeing or hearing things that others can’t
  • Thinking or talking about suicide

When a child has a mental illness, they may have some of the same symptoms as adults, like worrying too much or changes in sleep and eating habits.

You may also notice:

  • Changes in how they perform at school
  • Aggression or disobedience
  • Frequent nightmares
  • Lots of temper tantrums
  • They seem too sensitive to sights, sounds, smells, or touch
  • Odd or unusual behavior

Just because you notice one or two of these symptoms doesn’t mean you or your loved one has a mental illness.

Major life events, like the loss of a job or a loved one, can take a normal toll on your mood and ability to function. A physical illness, a new medication, or changes in dosage can cause some of these symptoms.

But it may be time to get help if:

  • You notice several of these signs.
  • They aren’t linked to any obvious event.
  • They last long enough to interfere with your life.

If you start treatment early, you may be able to delay or even prevent the most serious effects.

Get help from a doctor or mental health expert right away if you have thoughts about hurting yourself or someone else. In a mental health emergency, call 911 or the National Suicide Prevention Lifeline at 800-273-8255. The Lifeline is staffed 24 hours a day. 

If it’s not an emergency, call your primary care doctor. They can help connect you with mental health services. If you don't have a regular doctor, call your health insurance company or your state or county mental health authority.

You can find many resources online. For information about help you can get in your area, call or email the National Alliance on Mental Illness (800-950-6264 or [email protected]).

Or call the national Health and Human Services Substance Abuse and Mental Health Services Administration (SAMHSA) at 877-726-4727. This line is staffed Monday through Friday from 8 a.m. to 8 p.m. ET. 

Your doctor or counselor will want to know about all your symptoms, any changes in behavior, and whether you've had major life events that might explain what's happening.

Even if they find that you have a mental illness, it may take several visits to zero in on the correct diagnosis. Treatment often includes some combination of drugs and talk therapy. Support groups and lifestyle changes may also help.