Hostile Behavior: Meaning, Causes and What to Do

Hostile behavior meaning

In psychology, hostility has three parts:

• Attitude (cognitive): a cynical, distrustful view of others, expecting them to be unfair or mean. Psychologists call the tendency to read neutral actions as deliberate attacks hostile attribution bias.
• Emotion (affective): anger, resentment, contempt and irritation.
• Behavior: acting on those feelings, verbally or physically.

Hostile behavior is the third part. It ranges from subtle to obvious:

Doctors also separate reactive aggression (a hot-tempered response to frustration or perceived threat) from proactive aggression (cold, planned use of aggression to get something). Most hostility linked to mental and medical conditions is reactive.

Common causes of hostile behavior

Stress, pain and exhaustion

Chronic stress, ongoing pain, hunger, poor sleep and feeling overwhelmed lower the threshold for anger. People are more likely to snap at those closest to them.

Alcohol and drugs

Alcohol reduces inhibition and is involved in a large share of violent incidents. Stimulants (cocaine, methamphetamine), anabolic steroids, some synthetic cannabinoids and withdrawal from alcohol, benzodiazepines or opioids can all cause irritability and aggression. Ongoing problems point to a substance use disorder.

Mental health conditions

• Depression: irritability and anger are common, especially in men and teenagers, and can be more visible than sadness.
• PTSD: being constantly on guard (hyperarousal) leads to outbursts, especially when something triggers memories of the trauma.
• Bipolar disorder: irritability, arguments and aggression can occur during manic or mixed episodes.
• Anxiety: a person who feels trapped or panicked may lash out.
• ADHD: impulsivity and difficulty regulating emotions lead to quick-tempered reactions.
• Intermittent explosive disorder: repeated, sudden outbursts far out of proportion to the trigger, followed by regret.
• Personality disorders: hostility is common in borderline, antisocial and paranoid personality disorders.
• Psychosis: paranoid beliefs that others intend harm can lead to defensive hostility.

Brain conditions

• Dementia: damage to the frontal lobes, confusion, and inability to express needs cause agitation and aggression, often during personal care.
• Traumatic brain injury: frontal lobe injury reduces impulse control and can cause lasting irritability.
• Stroke, brain tumors and epilepsy can also change behavior.

Medical causes

Sudden hostility in someone who is normally calm can be a sign of a physical problem:

• low blood sugar (hypoglycemia)
• delirium from infection, dehydration or medicines, especially in older adults
• an overactive thyroid
• hormonal changes, such as premenstrual dysphoric disorder
• medicines such as steroids, levetiracetam and some sleeping pills

In children and teenagers

Hostility in children may reflect frustration, learning or language difficulties, ADHD, anxiety, exposure to violence at home, bullying, or oppositional defiant disorder and conduct disorder.

When to worry about hostile behavior

Seek help when hostility:

• is new or out of character, especially if it started suddenly
• is getting more frequent or more intense
• involves threats, damage to property or physical harm
• makes family members afraid or causes them to change how they act to avoid outbursts
• affects work, school or relationships
• comes with low mood, hopelessness, heavy drinking, hallucinations or confusion

What to do when someone is hostile

In the moment

• Keep yourself and others safe first. Leave if you feel threatened.
• Stay calm, speak slowly and quietly, and keep your body language open.
• Do not argue, threaten or touch the person.
• Acknowledge the feeling ("I can see you're really angry") without accepting abuse.
• Give the person space and a way to leave.

For a person with dementia

Look for an unmet need: pain, hunger, a full bladder, fear, noise or being rushed. Approach from the front, explain each step of personal care, and try again later rather than insisting.

If you are the one who is hostile

• Notice early warning signs: clenched jaw, racing heart, raised voice.
• Take a timeout of at least 20 minutes to let the body calm down.
• Use slow breathing: in for 4 seconds, out for 6 to 8 seconds.
• Cut down alcohol, and get regular sleep and exercise.
• Repair afterward: apologize and talk once you are calm.

How doctors assess hostility

A primary care doctor or mental health professional will ask when the behavior started, what triggers it, how often it happens, whether anyone has been hurt, and about mood, sleep, substance use, head injuries and medicines. They may screen for depression, PTSD and bipolar disorder, and check blood sugar, thyroid function and other blood tests if a medical cause is possible. In older adults, a sudden change prompts a search for delirium.

Treatment

• Treating the underlying condition, such as depression, PTSD, ADHD or a thyroid problem, often reduces hostility substantially.
• Cognitive behavioral therapy (CBT) and anger management programs teach people to recognize triggers, challenge hostile thoughts and respond differently.
• Substance use treatment when alcohol or drugs play a part.
• Medicines may be used for specific conditions, for example antidepressants, mood stabilizers or, short term, antipsychotics for severe aggression in psychosis or dementia.
• Family and parent training programs help with children's aggression.

For a deeper look at the conditions behind long-term hostility and how they are treated, see hostility and aggression as a clinical problem.

Frequently asked questions

What is the meaning of hostile behavior?

Hostile behavior means acting in an unfriendly, aggressive or antagonistic way toward others, with the aim of opposing, intimidating or hurting them. It includes insults, sarcasm, threats, the silent treatment and physical aggression.

What causes sudden hostile behavior?

Sudden hostility can result from stress, alcohol or drugs, but also from medical problems such as low blood sugar, delirium, infection, a head injury or medicine side effects. In older adults, sudden aggression should be checked by a doctor promptly.

Is hostility a mental illness?

Hostility itself is not a diagnosis. It is a behavior that can be part of many conditions, including depression, PTSD, bipolar disorder, intermittent explosive disorder, personality disorders and dementia. It can also occur in people without any mental illness.

What is the difference between hostility and aggression?

Hostility usually describes a negative attitude and angry feelings toward others. Aggression is behavior intended to harm, whether verbal or physical. A person can feel hostile without acting aggressively, though persistent hostility often leads to aggressive acts.

How do you deal with a hostile person?

Stay calm, keep a safe distance, avoid arguing, and acknowledge their feelings without accepting abuse. Leave if you feel unsafe. If the hostility is ongoing, encourage the person to seek help, and look after your own safety and support.