Mental health concerns are extremely common in adulthood, and they can affect how people think, feel, behave, and function in daily life. Some conditions show up as persistent worry or low mood. Others affect sleep, energy, relationships, motivation, or the ability to manage stress. While everyone experiences emotional ups and downs, a mental health disorder typically involves symptoms that are more intense, last longer, and interfere with work, school, relationships, or basic self-care.
Below are some of the most common mental health disorders in adults, along with what they can look like and why recognizing them matters.
Anxiety Disorders
Anxiety disorders are among the most common mental health conditions in adults. Anxiety is a normal stress response, but an anxiety disorder tends to involve persistent fear, worry, or physical tension that feels difficult to control.
Common Types Of Anxiety Disorders
- Generalized Anxiety Disorder (GAD): Ongoing worry about multiple areas of life, often paired with restlessness, muscle tension, irritability, or trouble sleeping.
- Panic Disorder: Sudden episodes of intense fear that can include chest tightness, shortness of breath, dizziness, and a sense of losing control.
- Social Anxiety Disorder: Strong fear of social situations, judgment, or embarrassment, often leading to avoidance.
- Specific Phobias: Intense fear of a specific trigger like flying, needles, or certain animals.
Anxiety disorders can also show up physically through stomach issues, headaches, rapid heartbeat, fatigue, and difficulty concentrating.
Depressive Disorders
Depressive disorders are also very common in adults and go beyond “feeling sad.” Depression can affect mood, thinking, motivation, appetite, sleep, and energy, often making everyday life feel heavy.
Common Types Of Depressive Disorders
- Major Depressive Disorder: Persistent low mood or loss of interest, often paired with changes in sleep, appetite, concentration, self-worth, and energy.
- Persistent Depressive Disorder (Dysthymia): A longer-lasting, lower-grade depression that can feel like a constant emotional fog or chronic low mood.
Some people experience depression as irritability, numbness, or burnout rather than sadness. It can also increase the risk of substance use as a form of self-medication.
Substance Use Disorders
Substance use disorders involve a pattern of alcohol or drug use that becomes difficult to control and continues despite negative consequences. This can happen with alcohol, opioids, stimulants, cannabis, sedatives, and other substances.
Common signs include cravings, tolerance, withdrawal symptoms, using more than intended, and difficulty cutting back. Substance use disorders frequently co-occur with anxiety, depression, trauma, and ADHD, which is why integrated care is often important.
Trauma-Related Disorders
Trauma can affect the brain and nervous system long after an event has ended. Trauma-related disorders are common in adults, especially when someone has experienced violence, abuse, accidents, medical trauma, or chronic childhood stress.
PTSD And Related Conditions
- Post-Traumatic Stress Disorder (PTSD): Symptoms may include intrusive memories, nightmares, avoidance of reminders, emotional numbing, irritability, hypervigilance, and feeling on edge.
- Complex Trauma Symptoms: Some adults experience long-term trauma effects involving shame, emotional dysregulation, relationship challenges, or feeling unsafe in the world.
Not everyone who experiences trauma develops PTSD, but many still benefit from trauma-informed support.
Bipolar Disorders
Bipolar disorders involve mood episodes that can include depression and periods of elevated or irritable mood.
- Bipolar I Disorder: Includes manic episodes that can involve reduced need for sleep, rapid speech, impulsive decisions, inflated confidence, or risky behavior.
- Bipolar II Disorder: Involves hypomanic episodes, which are less severe than full mania, along with major depressive episodes.
Bipolar disorders are sometimes misdiagnosed as depression or anxiety, especially if hypomanic symptoms are overlooked.
Obsessive-Compulsive Disorder
Obsessive-compulsive disorder (OCD) involves intrusive thoughts, images, or urges (obsessions) and repetitive behaviors or mental rituals (compulsions) aimed at reducing distress.
OCD is not simply being neat or organized. It can be time-consuming and exhausting, and it often causes significant anxiety and avoidance.
Eating Disorders
Eating disorders can affect adults of any age and gender, not only teens. They may involve restrictive eating, binge eating, purging behaviors, or intense distress about food and body image.
Common forms include anorexia nervosa, bulimia nervosa, and binge eating disorder. Eating disorders often overlap with anxiety, trauma, perfectionism, and depression.
Personality Disorders
Personality disorders involve long-term patterns in thinking, emotional response, and relationships that cause distress or impairment. Symptoms can include intense fear of abandonment, difficulty regulating emotions, unstable relationships, or rigid ways of coping.
It is important to note that having strong emotions or relationship struggles does not automatically mean a personality disorder. A qualified professional can help determine what is going on and what kind of support is most helpful.
Psychotic Disorders
Psychotic disorders, such as schizophrenia spectrum disorders, are less common than anxiety or depression, but they are still important. Symptoms can include hallucinations, delusions, disorganized thinking, and changes in functioning.
Early treatment can make a meaningful difference, especially when symptoms are identified and supported quickly.
Why Many Adults Have More Than One Condition
It is common for adults to experience more than one mental health condition at the same time. For example, anxiety and depression often overlap. Trauma can contribute to substance use. ADHD can increase stress and emotional dysregulation. This is why a thorough assessment matters, and why treatment plans often include more than one approach.
When To Seek Help
Consider reaching out to a professional if symptoms:
- Last for weeks or months
- Affect work, relationships, sleep, or daily functioning
- Lead to substance use or risky coping
- Include thoughts of self-harm or hopelessness
Support can include therapy, skills-based programs, medication when appropriate, lifestyle changes, and peer support.
The Bottom Line
The most common mental health disorders in adults include anxiety disorders, depressive disorders, substance use disorders, trauma-related disorders, bipolar disorders, OCD, eating disorders, personality disorders, and psychotic disorders. Many adults experience overlapping symptoms, and getting the right diagnosis can be a key step toward effective treatment. With the right support, mental health conditions are manageable, and many people improve significantly over time.
If you are searching for help for yourself or a loved one, consider ORCA Mental Health for IOP in San Diego.






