Evidence-Based Supplement & Herb Guides

Low Self-Esteem Disorder Overview: Signs, Risk Factors, and Effects

A clear guide to persistent low self-esteem, including symptoms, signs, causes, risk factors, complications, related mental health conditions, and when evaluation may matter.

Persistent low self-esteem can shape how a person interprets almost every part of life: relationships, work, school, appearance, mistakes, success, criticism, and even ordinary...

Loneliness Disorder Symptoms and Mental Health Effects

Learn what “loneliness disorder” means, how chronic loneliness can appear, what causes it, who is at higher risk, and when symptoms may need professional evaluation.

Loneliness can feel like being cut off from other people even when life looks socially “normal” from the outside. A person may have coworkers,...

Logorrhea and Pressured Speech: Symptoms, Causes, and Differences

Learn what logorrhea means, how excessive speech may appear, what conditions can cause it, and when sudden or severe speech changes may need professional evaluation.

Logorrhea means unusually excessive, rapid, or hard-to-interrupt talking. It is not usually treated as a stand-alone diagnosis. More often, it is a clinical sign...

Lithium Toxicity Symptoms, Signs, Causes, and Complications

Lithium toxicity can cause tremor, vomiting, confusion, poor coordination, kidney problems, and serious neurological complications. Learn the signs, causes, risk factors, diagnostic context, and when urgent evaluation matters.

Lithium is a prescription mood stabilizer used most often in bipolar disorder and, in some cases, other psychiatric conditions. It can be effective, but...

Limerence and Obsessive Romantic Fixation: Key Signs and Risks

A clear guide to limerence, including what it means, how symptoms appear, how it differs from love, OCD, and erotomania, and when emotional fixation may need professional evaluation.

Limerence is an intense state of romantic or emotional fixation on a specific person. It can feel euphoric when there is hope of reciprocation...

Lewy Body Dementia Overview: Cognitive, Movement, Sleep, and Hallucination Symptoms

Learn how Lewy body dementia affects cognition, movement, sleep, perception, risk factors, diagnosis, and complications, including signs that need professional evaluation.

Lewy body dementia is a progressive brain condition that can affect thinking, attention, movement, sleep, mood, perception, and daily function. It can be confusing...

Lethargy Syndrome Signs, Risk Factors, and Related Conditions

Learn what lethargy syndrome can mean, how it may appear, what conditions it can resemble, and when persistent or sudden lethargy may need professional evaluation.

Lethargy can be unsettling because it affects more than energy. A person may seem unusually slowed down, hard to engage, less motivated, emotionally flat,...

Learning Disorder Overview: Types, Risk Factors, and Diagnostic Clues

Clear guide to learning disorder symptoms, types, causes, risk factors, diagnostic context, common look-alikes, and possible complications in children, teens, and adults.

A learning disorder is a neurodevelopmental condition that makes certain academic skills unusually difficult to acquire and use. The difficulty is not simply a...

Late-Onset Depression: Signs, Risk Factors, and Diagnostic Context

Learn what late-onset depression means, how symptoms may appear in older adults, what it can be confused with, and why new depression later in life deserves careful evaluation.

Depression that first appears later in life can be easy to miss. It may not look like the familiar picture of sadness, crying, or...

Latent Schizophrenia: Meaning, Symptoms, Signs, Causes, and Risks

Latent schizophrenia is an older term for subtle or hidden schizophrenia-like symptoms. Learn what it may mean today, how it differs from modern diagnoses, and when professional evaluation matters.

Latent schizophrenia is an older and somewhat ambiguous term. In modern mental health diagnosis, it is not usually used as a formal diagnosis in...

Latent Inhibition Disorder Symptoms, Signs, Causes, and Clinical Meaning

A clear guide to low latent inhibition, why “latent inhibition disorder” is not usually a formal diagnosis, what symptoms may feel like, and when evaluation may matter.

Latent inhibition is the brain’s tendency to tune out familiar information that has not been important before. It helps a person ignore background details,...

Latah Overview: Startle Reactions, Echolalia, Echopraxia, and Risks

Latah is a culture-related startle syndrome marked by exaggerated surprise reactions, automatic speech or imitation, possible causes, risk factors, diagnostic considerations, and complications.

Latah is an uncommon startle-related condition most often described in Southeast Asian cultural settings, especially Malaysia and Indonesia. It involves an unusually intense reaction...

Language Disorder Causes, Risk Factors, and Related Conditions

Learn what language disorder means, how symptoms can appear across ages, what conditions it may resemble, and when language difficulties need professional evaluation.

Language is more than speaking clearly. It includes understanding words, building sentences, using grammar, finding the right words, following directions, telling stories, reading, writing,...

Lack of Empathy Disorder Symptoms, Signs, and Possible Causes

Understand what people often mean by “lack of empathy disorder,” why it is not a formal diagnosis, and how low empathy may relate to personality patterns, autism, trauma, neurological change, and safety concerns.

“Lack of empathy disorder” is a phrase people often use when someone seems cold, uncaring, manipulative, emotionally unavailable, or unable to understand how their...

Korsakoff Syndrome Explained: Symptoms, Diagnosis, and Complications

A clear guide to Korsakoff syndrome, including its memory symptoms, relationship to Wernicke encephalopathy, causes, risk factors, diagnostic context, and complications.

Korsakoff syndrome is a serious memory disorder caused by brain injury from severe thiamine, or vitamin B1, deficiency. It is most often linked with...

Koro Syndrome Overview: Genital Retraction Fear, Signs, and Causes

Learn what Koro syndrome is, how its symptoms appear, what can cause Koro-like fears, which conditions it may resemble, and when professional evaluation may be important.

Koro syndrome is a rare psychiatric condition in which a person becomes intensely afraid that their genitals, breasts, or another body part are shrinking,...

Kluver-Bucy Syndrome Explained: Symptoms, Brain Causes, and Risks

Clear overview of Kluver-Bucy syndrome, including hallmark symptoms, temporal lobe causes, risk factors, similar conditions, diagnostic context, and warning signs that may need urgent evaluation.

Kluver-Bucy syndrome is a rare neurobehavioral condition caused by damage or dysfunction in parts of the temporal lobes, especially areas involved in memory, emotional...

Kleptomania Overview: How Symptoms, Urges, and Complications Develop

Clear overview of kleptomania, including symptoms, warning signs, possible causes, risk factors, complications, and how clinicians distinguish it from shoplifting, OCD, addiction-like behavior, mania, and psychosis.

Kleptomania is a mental health condition in which a person repeatedly feels unable to resist urges to steal items they do not need for...

Kleine-Levin Syndrome Symptoms, Signs, Causes, and Complications

Kleine-Levin syndrome causes recurring episodes of extreme sleepiness with cognitive, mood, perception, and behavior changes. Learn the key symptoms, risk factors, diagnostic context, complications, and urgent red flags.

Kleine-Levin syndrome is a rare sleep and neuropsychiatric condition in which a person has repeated episodes of extreme sleepiness, unusually long sleep, and changes...

Katagelasticism Signs, Risk Factors, and Social Effects

Katagelasticism is the enjoyment of laughing at others, especially through ridicule or humiliation. Learn how it differs from teasing, bullying, and schadenfreude, and why it can affect relationships, work, and mental health evaluation.

Katagelasticism describes a persistent tendency to enjoy laughing at, mocking, embarrassing, or ridiculing other people. It is most often discussed as a personality-related trait...