Benzodiazepines: what are the effects?

The effects of any drug (including benzodiazepines) vary from person to person. How benzodiazepines affect a person depends on many things including their size, weight and health, also whether the person is used to taking it. The effects of benzodiazepines, as with any drug, also depend on the amount taken.

There is no safe level of benzodiazepine use. Use of any drug always carries some risk—even medications can produce unwanted side effects. It is important to be careful when taking any type of drug.

Immediate effects

The effects of benzodiazepines may start to be felt within an hour and, depending if they are short, intermediate or long acting, they can last from 2½ to 160 hours.

Low to moderate doses

Some of the effects that may be experienced after taking benzodiazepines include:

  • depression
  • confusion
  • feelings of isolation
  • feelings of euphoria
  • memory loss
  • impaired thinking
  • headache
  • drowsiness and sleepiness
  • vertigo (feeling dizzy, lightheaded and unsteady)
  • dry mouth
  • slurred speech or stuttering
  • double or blurred vision
  • tremors
  • impaired motor coordination
  • nausea
  • loss of appetite
  • vomiting
  • diarrhoea
  • constipation
  • fatigue
  • increased risk of accidents and falling over (especially for older people).

Higher doses

A high dose of benzodiazepines can cause a person to overdose. This means that a person has taken more benzodiazepines than their body can cope with.

Higher doses of benzodiazepines can result in drowsiness, over-sedation and sleep. They may produce an effect similar to drinking a large amount of alcohol. Other effects can include:

  • confusion
  • dizziness
  • jitteriness/excitability
  • slurred speech
  • loss of coordination
  • impaired judgement
  • difficulty in thinking clearly
  • memory loss
  • mood swings and aggressive behaviour.

Very high doses of benzodiazepines can cause:

  • slow, shallow breathing
  • unconsciousness
  • coma
  • death (when taken with alcohol or depressant drugs such as heroin).

Coming down

As the effects of benzodiazepines begin to wear off, a person may experience a range of effects the next day such as:

  • a general “hangover” effect
  • reduced alertness
  • sleepiness
  • headache.

Long-term effects

Some of the long-term effects of benzodiazepines are:

  • memory loss
  • confusion and difficulty thinking clearly
  • lethargy and lack of motivation
  • fatigue
  • headaches
  • drowsiness and sleepiness
  • difficulty sleeping and disturbing dreams
  • nausea
  • personality change and changes in emotional responses
  • anxiety
  • irritability, paranoia and aggression
  • depression
  • lack of motivation
  • weakness
  • fatigue
  • skin rashes
  • weight gain.

Other effects of benzodiazepine use

Taking benzodiazepines with other drugs

The chances of an overdose are increased if benzodiazepines are taken with other depressant drugs such as alcohol or opiates such as heroin. Taking benzodiazepines with other depressant drugs increases the risk of breathing difficulties and/or overdose.

If benzodiazepines are taken with stimulants such as amphetamines and ecstasy, the body is put under a lot of stress as it tries to deal with the competing effects.

Using benzodiazepines to help with the symptoms of the "comedown" after using stimulants can lead to a cycle of dependence on both drugs.

For more information, please click on the Australian Drug Foundation's DrugInfo Clearinghouse web site link below.
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Last Reviewed: 24 February 2012
Reproduced with kind permission from the Australian Drug Foundation.

References

Australian Drug Foundation. Drug Info. Benzodiazepine facts. Last updated 24 February 2012. http://www.druginfo.adf.org.au/drug-facts/benzodiazepines (accessed Jan 2013).
Australian Drug Foundation (ADF)

Australian Drug Foundation (ADF)

Vision: Healthy People, Strong Communities. Mission: Working together to prevent alcohol and other drug problems in communities.