Discovered in the 1930s and with the first agent, chlordiazepoxide, marketed in the 1950s, benzodiazepines have been part of drug therapy for decades.
Until benzodiazepines were introduced, barbiturates were the drugs used to treat anxiety and sleeplessness. But barbiturates were a worry with their narrow therapeutic margin (that is, their small or narrow difference between a therapeutic and deadly dose).
With benzodiazepines, the margin of safety is greater, and the drugs are as effective.
Benzodiazepines are central nervous system depressants, meaning they slow down brain activity by acting on neurochemicals such as gamma aminobutyric acid (i.e. GABA) within the nervous system. These are just the effects needed to treat anxiety and sleeplessness.
While some of the older benzodiazepines are no longer available, there are still a variety from which to choose, for example alprazolam, clonazepam, diazepam, flurazepam, lorazepam, oxazepam and temazepam.
Unfortunately, tolerance can become an issue, meaning the patient needs greater doses to obtain the same effect. Also, abuse is possible because these drugs act in the nervous system and can produce euphoria.
Another group of related drugs, the Z-drugs, were developed in order to avoid both the tolerance and abuse potential. However, these drugs (for example zolpidem and zopiclone) proved as problematic.
Some 12 per cent of Canadians use one or more of these drugs. Usage is highest among older individuals, perhaps because they started taking these drugs when they were younger and continue to do so, or maybe because older individuals have more problematic anxiety and/or sleep complaints.
In addition to tolerance and abuse issues, additional effects can include drug-induced drowsiness and cognitive impairment. Driving and performing any tasks that require mental capacity are not recommended when taking either benzodiazepines and/or Z-drugs. A European study showed that people taking Z-drugs have twice the risk for a car accident compared to others not taking these drugs.
For older adults, adverse effects can be especially marked if there is already cognitive impairment such as dementia. As well, adverse effects increase the risk for dizziness and for falls with the potential for broken bones.
Research has shown the risk for hip fractures increases by at least 50 per cent if benzodiazepines are used in the elderly. As well, older bodies do not metabolize these drugs as efficiently, meaning they remain in the body longer with even more adverse effects.
Ideally, benzodiazepines and Z-drugs should only be used for the shortest period of time possible and they should also be used along with non-drug approaches to treating the diagnosis. Nor should these medications be taken along with any other drugs that also cause sedation, such as narcotic analgesics, gabapentin, dimenhydrinate, diphenhydramine, and yes, even alcohol.
However, there are several instances where benzodiazepines and/or Z-drugs may be appropriately used. For example, in some psychiatric conditions or for some types of seizure diagnosis they may be prescribed for long periods of time. Specialists usually begin the therapy, then ongoing therapy successfully treats the specific symptoms.
Stopping benzodiazepines and/or Z-drugs can be difficult, requiring a tapering of the dose over several weeks or months. For anxiety and sleep problems, non-drug approaches are ideal, and if a benzodiazepine and/or a Z-drug is needed, then it should be the lowest dose for the shortest possible time. Overall health might be better without these drugs.