Which of the benzodiazepines is the strongest

Benzodiazepines

  1. Home
  2. Drug groups

Benzodiazepines are substances with a heterocyclic ring system that contains two nitrogen atoms. The prototype is diazepam. The pharmacological spectrum of benzodiazepines includes anxiolytic, sedative, muscle-relaxing and anticonvulsant effects as well as a depressant effect on the autonomic endocrine system.

Tranquilizers, tranquilizers

application

The psychiatric fields of application of the benzodiazepines include:

In addition, benzodiazepines are widely used for the symptomatic treatment of anxiety, tension and excitement as well as sleep disorders.

In neurology, substances from this group are used as anti-epileptic drugs (e.g. diazepam, clonazepam, clobazepam and lorazepam).

Sedating benzodiazepines such as B. Midazolam are used in diagnostic procedures and in anesthesiology.

Tetrazepam in particular is still used as a centrally acting muscle relaxant. Due to the risk of addiction in long-term use, it should only be used for a short time.

In old age and with impaired liver function, the usual dose of benzodiazepines should be reduced due to slow elimination.

effect

The effect of the benzodiazepines is linked to the presence of endogenous gamma-aminobutyric acid (GABA). All substances in this group exert their pharmacological effect by binding to the modulatory benzodiazepine binding site of the transmembrane GABAA.Receptor. In doing so, they increase the affinity of the neurotransmitter GABA to its GABA binding siteA.Receptor. This results in an increased opening frequency of GABA-controlled chloride ion channels and thus an increased hyperpolarization of the cell (i.e. increased GABAergic inhibition).

The potency of a benzodiazepine is determined by its chemical structure and the associated affinity for the benzodiazepine binding site. The duration of action of the individual benzodiazepines differs greatly from one another and is primarily determined by the rate of metabolic breakdown and the formation of pharmacologically active metabolites.

Clinically, the benzodiazepines are divided into short, medium and long-acting substances.

Side effects

The following side effects can occur with benzodiazepine therapy:

  • Fatigue, drowsiness, poor concentration
  • Impairment of alertness and ability to react
  • Muscle weakness (as a result of central muscle relaxation)
  • Respiratory disorders up to respiratory depression (especially in combination with alcohol)
  • Mnestic disorders (especially after IV administration and with substances that quickly pass into the brain such as midazolam)
  • Anterograde amnesia
  • Paradoxical effects (e.g., arousal and irritability, insomnia)
  • Drop in blood pressure, respiratory depression and cardiac arrest (rarely) are observed after i.v. Gift possible
  • Dependency and abuse potential

The active ingredients in this group can make you psychologically and physically dependent, especially when used over a longer period of time. Withdrawal symptoms are possible with rapid withdrawal.
With chronic use, the induction of dementia syndromes in old age is possible.

Interactions

Mutual reinforcement of the effect is possible through centrally damping drugs such as B.

Benzodiazepines are broken down with the help of isoenzymes of the cytochrome P450 system (especially CYP3A4 and CYP2C19). Medicinal products / active substances used at the same time, which are also substrates of these isoenzymes, can consequently change the pharmacokinetics of the benzodiazepines. Known CYP3A or CYP2C19 inhibitors (e.g. cimetidine and omeprazole) can lead to deepened and prolonged sedation.

Contraindication

  • Hypersensitivity to the active ingredient
  • Severe respiratory failure
  • Addiction history
  • Myasthenia gravis
  • Pregnancy (use only in exceptional cases if there is a compelling indication and taking into account the risk to the child)
  • Breastfeeding

Complete precautions can be found in the technical information for each representative.

Alternatives

Other anxiolytics such as B .:

  • Carbamates
  • Diphenylmethane derivatives
  • Buspirone

Other hypnotics / sedatives, such as B .:

Other centrally acting muscle relaxants such as B .:

Active ingredients

The benzodiazepines include, for. B. the following active ingredients:

Hints

The competitive benzodiazepine antagonist flumazenil can be used to treat severe benzodiazepine poisoning (with respiratory depression).

  1. Aktories K. et al., General and Special Pharmacology and Toxicology. 2017, 12th edition
     
  2. Medicinal product information