Anxiolytics

Anxiolytics reduce anxiety, psychological tension, fear (phobia), stress, nervousness etc. They are not suitable for the treatment of psychosis. Fear and anxiety are normal experiences, they do not have to be pathological symptom. It is not easy to decide in which case we can omit prescribing medication or where we need to use the pharmacotherapy or psychotherapy. The use of Anxiolytics is generally appropriate in individuals where the fear and anxiety cause somatic difficulties (heart palpitations, diarrhoea, sweating etc.).

Pharmacotherapy should be applied the shortest time possible, in order to get over the main live crisis which led to anxiety. However, in some cases, we cannot avoid long term administration of drugs. The disadvantage of using anxiolytics is the fact that some individuals prefer pharmacotherapy over dealing with complicated situations, so after that the drug dependence is highly probable.

The ideal anxiolytic should not influence the alertness. So far, the medication with this property is not available. The Anxiolytics lead to drowsiness, fatigue, lowering down the alertness. It´s central supressing effect causes myorelaxation, it is also use for anticonvulsive therapy.

The effects of anxiolytics can be described as: anxiolytic, sedative and hypnotic, myorelaxative, anticonvulsive. It´s mutual proportion are variable, it depends on properties of an individual drug.

Propandiol derivates
This class of medication has significant myorelaxative effect. The anxiolytic effect is weaker.

Guaifenesin has anxiolytic and myorelaxative effects. It is used for psychosomatic diseased with heart palpitations, inu algic syndromes (psychological tensionn with headache). It is combined with anagetics-antipyretics agents for it´s synergism outcome. It is suitable for overcoming nervousness during public speeking.

Benzodiazepines
In this indication, we use agents with predominant anxiolytic effect.

We divide benzodiazepines anxiolytics by their half-life (t1/2)'''; the standard daily dosage for anxiolytic effect is mentioned in brackets
 * with long half-life t1/2 (> 24 hours):
 * diazepam (5–40 mg), medazepam (10–60 mg), clobazam (20–30 mg), clonazepam(1–8 mg), chlordiazepoxid (10–50 mg);
 * the biotransformation is done by oxidation in the liver;
 * the elimination is prolonged in patients with liver disease and in elderly patiets.


 * with medium half-life t1/2 (12–24 hours):
 * alprazolam (0,5–4 mg), bromazepam (3–15 mg);


 * with short half-life t1/2 (< 12 hours):
 * xazepam (30–90 mg), tofizopam (50–300 mg), lorazepam (2–6 mg);
 * their are metabolized by conjugation with glucuronides with significantly lower dependance on liver function

Other non benzodiazepines anxiolytics

 * buspiron - 5-HT1A receptor agonist. The effect is comparable to benzodiazepines, it´s downside is a slow onset of action (1-2 weeks). It does not have major side effect  which are typical for benzodiazepines anxiolytics (there is no risk for dependence, fatigue, memory and concentration problems, etc.)
 * antihistaminics (hydroxyzin, promethazin) - better tolerated, lower efficiency than benzodiazepines

Related articles

 * Psychofarmaka
 * Hypnotika
 * Sedativa
 * Abúzus návykových látek
 * Benzodiazepiny
 * Procvičování:Anxiolytikum

Literature
Ústav farmakologie LF UK v Hradci Králové. Vybrané kapitoly z klinické farmakologie pro bakalářské studium : Hypnotika, sedativa [online]. ©2010. [cit. 2010-07-01]. < https://www.lfhk.cuni.cz/farmakol/predn/bak/kapitoly/ichs-bak.doc/ >