Evidence-Based Supplement & Herb Guides

Depression Symptoms, Signs, Causes, Risk Factors, and Complications

A clear, medically grounded overview of depression symptoms, signs, causes, risk factors, diagnostic context, and possible complications, including warning signs that may need urgent evaluation.

Depression is more than a period of sadness or a reaction to a difficult week. It is a mental health condition that can change...

Depression with psychotic features: causes, risks, symptoms, and safety concerns

Learn how depression with psychotic features can affect mood, beliefs, perception, safety, and daily functioning, including key symptoms, risk factors, diagnostic context, and complications.

Depression with psychotic features is a serious form of depressive illness in which symptoms of depression occur together with psychosis, such as delusions, hallucinations,...

DepersonalizationDerealization Disorder Explained: Symptoms, Causes, and Complications

A clear guide to depersonalization-derealization disorder, including how symptoms feel, when they may signal a disorder, possible causes, risk factors, diagnostic context, and complications.

Depersonalization-derealization disorder is a dissociative condition in which a person repeatedly or persistently feels detached from themselves, their body, their emotions, their memories, or...

Dependent Personality Disorder and Fear of Abandonment: Key Signs and Risks

Clear overview of dependent personality disorder, including core symptoms, relationship signs, possible causes, risk factors, diagnostic context, related conditions, and safety concerns.

Dependent personality disorder is a mental health condition marked by a persistent and excessive need to be cared for, often with intense fear of...

Dementia Overview: Early Signs, Causes, and Complications

Understand dementia symptoms, early warning signs, major causes, risk factors, complications, and how clinicians distinguish dementia from normal aging and other causes of confusion.

Dementia is a clinical syndrome in which changes in memory, thinking, behavior, or daily functioning become significant enough to interfere with independence. It is...

Delusional Parasitosis: Signs, Risk Factors, and Diagnostic Context

A clear guide to delusional parasitosis, including symptoms, visible signs, possible causes, risk factors, diagnostic context, related conditions, and complications.

Delusional parasitosis is a serious psychiatric condition in which a person becomes firmly convinced that parasites, insects, worms, mites, fibers, or other organisms are...

Delusional Disorder Causes, Risk Factors, and Common Delusion Types

Understand delusional disorder symptoms, common delusion themes, possible causes, risk factors, diagnostic context, complications, and warning signs that may require urgent evaluation.

Delusional disorder is a psychiatric condition in which a person develops one or more firmly held beliefs that are not based in reality and...

Delirium Causes, Types, Symptoms, and Serious Complications

Understand delirium as a sudden change in attention, awareness, and thinking, including key symptoms, causes, risk factors, diagnostic context, and serious complications.

Delirium is a sudden change in mental state that affects attention, awareness, thinking, and behavior. It can make a person seem confused, unusually sleepy,...

Delayed Sleep Phase Disorder Overview and Diagnostic Context

Delayed sleep phase disorder shifts sleep and wake times later than daily life allows. Learn the key symptoms, causes, risk factors, diagnostic context, daily effects, and complications.

Delayed sleep phase disorder is a circadian rhythm sleep-wake condition in which a person’s natural sleep timing is shifted much later than the schedule...

Cyclothymic Disorder Signs and Symptoms: Causes, Risk Factors, and Diagnosis Context

Learn what cyclothymic disorder is, how symptoms appear over time, what can cause or increase risk, how diagnosis is considered, and what complications may occur.

Cyclothymic disorder is a long-term mood disorder marked by repeated shifts between hypomanic symptoms and depressive symptoms that do not meet the full criteria...

Cycloid Psychosis Overview: Acute Symptoms, Causes, and Lookalikes

Learn what cycloid psychosis means, how symptoms may appear, what conditions can resemble it, and why sudden fluctuating psychosis requires careful diagnostic evaluation.

Cycloid psychosis is a rare and diagnostically complex form of acute psychosis marked by sudden onset, rapidly changing symptoms, and prominent shifts in mood,...

Cotard Delusion Signs and Symptoms: Causes, Risks, and Complications

Learn what Cotard delusion is, how nihilistic beliefs can appear, which conditions may be associated with it, and why urgent evaluation may be needed when safety, eating, drinking, or reality testing are affected.

Cotard delusion is a rare but serious form of psychotic belief in which a person is convinced that they are dead, do not exist,...

Coprolalia Signs, Risk Factors, and Diagnostic Context

Learn what coprolalia means, how it differs from intentional swearing, why it is linked to tic disorders, and when sudden or distressing symptoms need professional evaluation.

Coprolalia is an involuntary tic-like vocal behavior in which a person says obscene, offensive, taboo, or socially inappropriate words or phrases. It is best...

Conversion Disorder and Functional Neurological Disorder: Symptoms and Signs

Learn what conversion disorder means, how symptoms and clinical signs can appear, what causes and risk factors may be involved, and when neurological symptoms need urgent evaluation.

Conversion disorder is a condition in which a person develops neurological symptoms, such as weakness, tremor, seizure-like episodes, numbness, vision changes, speech problems, or...

Conduct Disorder Explained: Symptoms, Types, Causes, and Warning Signs

Conduct disorder involves persistent aggression, deceit, rule violations, or harm to others. Learn the key symptoms, signs, causes, risk factors, diagnostic context, and complications.

Conduct disorder is a serious childhood or adolescent mental health condition involving a repeated pattern of behavior that violates the rights of others, major...

Communication Disorder Types, Warning Signs, and Related Conditions

Learn what communication disorder means, including key symptoms, signs, causes, risk factors, overlapping conditions, diagnostic context, and possible complications.

A communication disorder affects how a person understands, produces, uses, or organizes language and speech. It can involve spoken language, speech sounds, fluency, voice,...

Cognitive Disorder Not Otherwise Specified: Symptoms, Signs, Causes, and Diagnostic Context

Learn what Cognitive Disorder Not Otherwise Specified means, how it relates to modern neurocognitive diagnoses, and what symptoms, causes, risks, complications, and warning signs may matter.

A cognitive diagnosis can feel confusing when the wording is broad, outdated, or unfamiliar. “Not otherwise specified” does not describe one single disease. It...

Cognitive Behavioral Disorder Overview, Symptoms, Causes, and Risk Factors

Learn what cognitive behavioral disorder can mean, including common cognitive and behavioral symptoms, possible causes, risk factors, diagnostic context, complications, and urgent warning signs.

“Cognitive behavioral disorder” is not usually used as a single formal diagnosis in major psychiatric classification systems. In clinical language, it is better understood...

Claustrophobia: Overview, Symptoms, Causes, and Risk Factors

Claustrophobia is an intense fear of enclosed or hard-to-exit spaces. Learn how symptoms, triggers, causes, risk factors, diagnosis, and complications are understood.

Claustrophobia is an intense fear of enclosed, crowded, or hard-to-exit spaces. It is more than ordinary discomfort in a small room or elevator; for...

Circadian Rhythm Sleep Disorder Symptoms, Signs, and Complications

Circadian rhythm sleep disorder can cause insomnia, daytime sleepiness, mood changes, and impaired functioning when the body clock is out of sync with daily demands. Learn the main types, symptoms, causes, risk factors, complications, and diagnostic context.

Circadian rhythm sleep disorder occurs when the body’s internal timing system is out of sync with the sleep-wake schedule a person needs for daily...