Benzodiazepines and their most unknown side effects

Benzodiazepines and their most unknown side effects

Today, nobody is surprised to hear that a family member is taking sleeping pills. Even we have been able to take some medication at a specific time to help us fall asleep. Indiscriminate consumption of these drugs is completely normalized in our society, and especially in our elders, which many consider to be a panacea when there are insomnia problems.


  • 1 Use of Benzodiazepines
  • 2 BZD short-term and long-term effects
  • 3 BZD and dependency risk
  • 4 BZD and sleep (alteration of sleep rhythms)
  • 5 Cognitive functioning
  • 6 BZD in the elderly
  • 7 BZD and paradoxical effect
  • 8 BZD and pregnancy
  • 9 BZD and suicide
  • 10 Reflection

Use of Benzodiazepines

Benzodiazepines are usually prescribed (BZD, from now on) to address these types of difficulties. BZDs are very popular drugs with hypnotic-sedative and anxiolytic effects which are prescribed in many psychiatric pathologies (panic, generalized anxiety, social phobia, depression, bipolar disorder ...) and even used as anticonvulsants or muscle relaxants. Historically, they appear to replace barbiturates, because they are not very specific and have a narrow therapeutic range, which means that there is a very small limit between the therapeutic dose and the risk of toxicity.

BZDs are much safer drugs than their predecessors but not as selective as we think, and due to this lack of specificity they have side effects that deserve to be considered by their users. They are drugs that act on the GABA, neurotransmitter that is responsible for transmitting an inhibitory message to the neurons with which it contacts to decrease their activity. Therefore and broadly speaking, the BZD acts as a central nervous system brake. They produce a relaxing and calming effect for the brain, so this depressing function decreases the activity of our body.

We expose the possible depressant effects in our body linearly:

Effect: anxiolytic -> sedative -> hypnotic -> anesthetic -> death

I do not intend, in this space, to delve into the biological, chemical or physiological components of the BZD. I just want to convey the dangers and possible side effects of chronic and abusive use of this substance, since I consider it our job to report both the positive aspects of these drugs and raise awareness about their main handicaps. We will perform a simple classification according to the half-life (VM) of the drug in our body to facilitate the understanding of these substances. To make it simpler, almost all (non-commercial) names of a BZD end in -am.

Benzodiazepine types

  • Short VM (1-4 hours): Increased risk of dependence and more side effects (triazolam, midazolam ...).
  • Intermediate VM (6-12 hours): (alprazolam, lorazepam, lormetacepam, oxacepam ...).
  • Long VM (12-100 hours): Daytime sedation risk but lower risk of dependence (diazepam, flurazepam, clonazepam, chloracepate ...).


TriazolamHalcionAlprazolamTrankimazinClobazamClarmyl, Nalafren
BentazepamThiadiponeLorazepamOrfidal, IdalpremChlorazepateTranxilium
 LormetazepamNoctamid, LoramedDiazepam


 OxacepamAdumbran, SuxidineFlurazepamSleeper

Before moving on to the negative effects of these substances, we must clarify that, although not everyone who consumes BZD suffers these effects, the risks are significant. What I expose here is a synthesis work with the objective of making an accessible classification of the possible repercussions of these drugs in different areas and facets.

BZD short-term and long-term effects

We know and recognize its effectiveness in the short term, approximately two to four weeks of use but, it is worth noting that the side effects associated with long-term consumption may occur in the form of deficiencies in cognitive skills, memory problems, mood swings… Another clinically significant symptomatology that may be associated is: emotional cloudiness, irritability, lethargy, sleep problems, personality changes, daytime sleepiness, aggressiveness, depression, agoraphobia, anxiety and panic attacks, social deterioration and work problems.

If we start to highlight the side effects with a more physiological or somatic component, we can find: drowsiness, vertigo, stomach upset, nausea, blurred vision and other vision changes, headache, coordination disorders, heart rhythm disorders , tremor, weakness, fatigue, chest pain, jaundice, vomiting ...

BZD and dependency risk

One of the serious consequences of the consumption of these substances, in the long term, is the possible dependency risk that generates, due to its addictive potential. We understand addiction as the organism's dependence on some drug that has become accustomed through a continuous process of consumption and where there is a need and impulse to ingest it.

The use maintained in the time of the BZD produces tolerance, reason why the habitual dose of the substance generates less effects, with what it is necessary to increase the doses so that the same effects are obtained.

By sharing group and mechanism of action with other depressant drugs such as alcohol, the consumption of BZD can generate cross tolerance with it. Thus, the consumer of BZD can develop greater tolerance to alcohol even if he has not consumed it and in addition, BZD can reduce alcohol withdrawal syndrome, which is why BZDs are often used for detoxification of alcohol-dependent patients.

In addition, the person may suffer withdrawal from these substances, which consists of the physical reaction that occurs before the interruption of the use of a drug to which the subject is accustomed and is dependent on it. BZD withdrawal syndrome is similar to those produced by alcohol consumption, since it shares classification with this one in the group of depressing substances of the central nervous system, as we have said before. Withdrawal symptoms can range from anxiety, delusions, insomnia, confusion, nausea, paraesthesia, hot flashes, muscle stiffness, paraesthesia, mydriasis... This syndrome may occur suddenly or gradually.

Finally, a poisoning by BZD, in particular when combined with depressant substances such as alcohol or other sedative drugs, can trigger a comatose or stuporous state. The muttering language, incoordination, unstable gait or impaired attention and memory It is the symptomatology that typically occurs in BZD poisoning.

BZD and sleep (alteration of sleep rhythms)

BZD may be useful for the short-term treatment of insomnia. As we have commented in the previous paragraph, its use is recommended only for a period of two to four weeks, due to the risk of developing a dependency.

These substances partially improve sleep-related problems as they shorten the time needed to fall asleep and prolong the total time you sleep. However, worsen the quality of sleep increasing light sleep and decreasing deep sleep. Therefore, these substances modify the architecture of sleep blocking deep sleep (mainly phase IV or slow wave) and the dream Rem. We have to know that phase IV of the slow wave dream has a decisive importance since it is precisely in this phase when brain temperature decreases, muscle tone is reduced and the brain rests. Feeling rested, both physically and psychically, after sleeping hours depends mainly on this phase. Some studies relate this phase to the consolidation of memory and learning and with the release of growth hormone (GH), so we can deduce that it is not highly recommended to block this phase.

We can stay with that, in general, the BZD shorten the time it takes us to fall asleep (phase I) and can prolong the sleep time but, as a consequence of this, the quality of sleep worsens, increasing light sleep (phase II ) and significantly reducing the phases of deep sleep (phases III-IV), more decisive for an optimal and integral rest.

Another disadvantage of hypnotics, including BZDs, is that they can cause, paradoxically, rebound insomnia since their withdrawal is characterized by a prolonged period of anxiety and agitation that make it difficult to fall asleep.

Cognitive functioning

Chronic consumption of these drugs can cause widespread cognitive problems, including difficulties with sustained attention, verbal learning, memory and psychomotor ability, motor coordination and reasoning temporal space.

One of the highlights in the books is their affectation on anterograde memory, which can cause amnesia of this type. To understand each other, we lose the ability to add new memories, so the learning and memory processes deteriorate directly. This is one of the reasons why prescribing benzodiazepines to children is avoided, since they reduce concentration and hinder their school performance. With the above we can deduce that they are not very recommended for activities such as driving or in tasks where the requirement of perceptual-attention resources is crucial.

BZD in the elderly

In this population, long-term consumption of BZD implies a risk factor for amplifying cognitive impairment, which sometimes can be confused with demented states. These difficulties in the cognitive faculties are associated with the dullness and lethargy produced by these substances. Some studies indicate that its consumption is associated with an increased risk of developing dementia in the future, although more research is needed in this direction.

Long-term consumption of BZD in the elderly can cause a drug syndrome with symptoms such as drowsiness, ataxia, fatigue, confusion, asthenia, vertigo, dizziness, syncope, reversible dementia, depression, intellectual deficiency, psychomotor and sexual dysfunction, anxiety, auditory and visual hallucination, paranoid ideation, panic, delusions, depersonalization, sleepwalking, aggressiveness, hypotension orthostatic and insomnia.

It has also been observed that there is a increased risk of falls by sedation and muscle relaxation. They can also occur confusional or disorienting cadres.

It should be noted that the interruption or discontinuation of these drugs leads to an improvement in both cognitive functions and in the stability and coordination of the elderly.

BZD and paradoxical effect

Exceptionally, BZDs can cause paradoxical excitement, even with increased irritability Y tendency to hostility. This behavioral disinhibition can occur accompanied by talkativeness, excitement, excessive movement, aggressiveness, emotional lability ...

This type of reaction is more common in children, but also occurs in the elderly, in patients with developmental disorders as well as people with alcoholic habits and with psychiatric and personality disorders.

BZD and pregnancy

BZD can cause teratogenic effects, so its use during pregnancy is contraindicated since they can cause malformations in the fetus.

BZD and suicide

Among all the exposed data, these are the least contrasted since there are only a few studies that link BZD with a higher risk of suicide. Although there is not much volume of data in this direction nor an exhaustive empirical contrast, we must take this information into account with patients who present suicidal ideation.


According to the comments and although it seems inconsistent with my words, I want to make it clear that I am not against the administration of BZD when they exist clinically significant reasons, always considering, and individually, the doses, the treatment time and the pattern of a gradual withdrawal. Keep in mind that prescribing anxiolytics as churros can generate more difficulties than solutions for patients and, greater healthcare costs for our economy. I care more about the first consequence since, the person who goes to the office for occasional insomnia problems and starts to consume BZD, if there is no control and comprehensive monitoring in this regard, after a few months there may still be those sleep problems that were a reason for consultation but now we can also add a substance use disorder (due to its great addictive potential). In addition, they may have suffered some of the specific symptoms that we have mentioned in the previous paragraphs. Sometimes the remedy can be worse than the disease.

I want the final wedge of this article to be a reflection since, psychology directly addresses the problem that attempts to alleviate the use of these drugs in a less invasive way. We probably need more time and our total willingness and willingness to achieve results. Perhaps it costs us more since it requires us much more involvement than taking a pill and depositing our "healing" in something external to us. The positive thing is that, for example, a behavioral stimulus control technique to treat an insomnia problem has no risk to our health and if we work with appropriate tools, the objectives can not only be achieved but also completely overcome. In addition, with all this you can avoid the risks associated with chronic medication consumption and reduce, in the long term, the costs of our treatment.