Benzodiazepines is the name given to minor tranquillizers most often prescribed for anxiety, tension and insomnia. This group includes diazepam (valium), chlordiazepoxide (librium), lorazepam (ativan) etc. These are usually prescribed as pills but do come in injectable form. Benzodiazepines seem to be prescribed most commonly to women for anxiety-related problems, often on long term repeat prescriptions. The patient may not see their GP regularly, and this can lead to chronic over-prescribing, long past the usefulness of the drug to alleviate the anxiety . It is estimated that approximately 25% of people prescribed benzodiazepines long term are appropriately prescribed. The remaining 75% should be prescribed only in the short term and encouraged to seek alternative forms of treatment (psychological counselling, anxiety management etc).

However, benzodiazepines are extremely useful drugs, and are particularly effective in the treatment of status epilepticus and other convulsive disorders; as a premedication, and in the treatment of acute anxiety.

Benzodiazepines were originally introduced into the prescribing repertoire to replace the barbiturate group of drugs in the 1960's in the belief that benzodiazepines were non-addictive. It is only over the last few years that attitudes towards this drug group have started to change.


Although benzodiazepines do not cause drowsiness or poor co-ordination at low doses, they do depress mental activity. Lack of concentration, co-ordination and memory may occur when the drug is first used but this passes after a couple of weeks use. It can generally be expected that benzodiazepines will relieve anxiety and tension by inducing a sense of calm and relaxation. Unlike the barbiturate group which focus their action on the spinal column to make the body sloppy and numb, benzodiazepines target areas of the brain and allow tranquillity without the physical depressant effect.

At higher doses, drowsiness can occur; concentration is affected such that the user can experience a feeling of disassociation where they can not co-ordinate mental intent with physical performance. This is often followed by sleep. If longer acting benzodiazepines have been used (eg, diazepam) the drug will still be present in the body on waking and the user is likely to feel sluggish and unrested.

The risk of fatal overdose on benzodiazepines in pill form is relatively low compared with barbiturates, probably because it can take up to 3 hours for the drug to enter the blood stream. However, if taken in conjunction with other depressant drugs the risk increases.


Tolerance develops fairly fast to the anxiety-reducing effects of benzodiazepines and unless the dose is steadily increased (or changed from short to long acting types), the pills become psychoactively inadequate over several weeks. After a period of months use, the body seems to hit a ceiling limit beyond which the drugs are taken to keep at bay the symptoms of withdrawal, but tranquillity is no longer achieved.

The range and severity of withdrawal varies from person to person, and from day to day. Symptoms include sweating, panic attacks, palpitations, insomnia, feelings of unreality and disassociation, lack of co-ordination and concentration, and distortions in perception (lights, noises etc experienced as intense and painful). Some users experience agoraphobia and a severe lack of self-confidence.

A good rule of thumb is that the withdrawal symptoms may last a month for every year the benzodiazepines have been taken - this is only a guide as each user's degree of psychological and physical dependence is different. However, it seems clear that withdrawal should be done slowly to minimize the discomfort, and with the knowledge of the user's GP.



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