Obsessive-compulsive disorders (OCD) are mental health conditions characterized by recurring, intrusive thoughts (obsessions) and/or ritualized behaviors (compulsions).

Those affected usually experience these thoughts as distressing, exaggerated, or unreasonable, yet feel internally driven to perform certain actions in order to reduce anxiety or tension.

The disorder can be highly burdensome and significantly impact daily life, work, and relationships. Early treatment significantly improves the prognosis.

Symptoms

Obsessions:

  • Recurrent, intrusive thoughts or images

  • Fear of contamination or infection

  • Checking or doubt-related thoughts

  • Aggressive or sexual thoughts (unwanted and distressing)

Compulsions:

  • Excessive washing or cleaning

  • Checking (e.g., doors, stove)

  • Counting, arranging, or repeating certain rituals

  • Mental rituals (e.g., repeated internal praying or neutralizing)

Rituals usually serve short-term anxiety reduction but reinforce the obsessive-compulsive cycle in the long term.

Types

  • Washing and cleaning compulsions

  • Checking compulsions

  • Ordering and symmetry compulsions

  • Obsessions without visible rituals

  • Mixed forms

The exact manifestation varies individually.

Causes

The development is multifactorial:

  • Neurobiological factors (changes in specific brain networks)

  • Genetic predisposition

  • Learning experiences

  • Increased sense of responsibility or perfectionism

  • Stress and distressing life events

In most cases, several factors interact.