Betahistine
| Structural formula | ||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
||||||||||||||||||||||
| General | ||||||||||||||||||||||
| Non-proprietary name | Betahistine | |||||||||||||||||||||
| other names |
|
|||||||||||||||||||||
| Molecular formula | C 8 H 12 N 2 | |||||||||||||||||||||
| External identifiers / databases | ||||||||||||||||||||||
|
||||||||||||||||||||||
| Drug information | ||||||||||||||||||||||
| ATC code | ||||||||||||||||||||||
| Drug class | ||||||||||||||||||||||
| properties | ||||||||||||||||||||||
| Molar mass | 136.19 g mol −1 | |||||||||||||||||||||
| Physical state |
firmly |
|||||||||||||||||||||
| density |
0.98 g cm −3 |
|||||||||||||||||||||
| Melting point | ||||||||||||||||||||||
| pK s value |
3.5; 9.7 |
|||||||||||||||||||||
| solubility |
Dimesilate: very light in water; easy in ethanol , very difficult in 2-propanol |
|||||||||||||||||||||
| safety instructions | ||||||||||||||||||||||
|
||||||||||||||||||||||
| As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions . | ||||||||||||||||||||||
Betahistine is a drug that is used in the treatment of dizziness, in particular Menière's disease and hydrops cochleae , although a controlled study has not yet been able to prove its effectiveness in these diseases. It acts as an H 3 antihistamine that also acts as an agonist at the H 1 receptor.
Clinical information
Application areas (indications)
Betahistine is used for disorders of the vestibular apparatus such as the symptoms of Meniere's disease , including: a. Dizziness, ringing in the ears, headache, nausea, vomiting and hearing impairment.
Dosis, kind and Time of the Use
8 mg three times a day to 16 mg three times a day for a period of at least three months. In practice, a dosage of 6–12 mg three times a day is usual. These details refer to the common salt of the active ingredient betahistine dimesilate. In order to avoid stomach intolerance, it is recommended to take it after a meal.
Contraindications (contraindications)
Pheochromocytoma , gastric and intestinal ulcers, bronchial asthma , hypersensitivity to betahistine, pregnancy.
Drug interactions
Antihistamines reduce the effectiveness of betahistine.
Use during pregnancy and breastfeeding
The use of betahistine is contraindicated during pregnancy and breastfeeding.
Adverse effects (side effects)
Frequency not known:
- Volatile rash with reddening of the skin and wheals
- Headache, drowsiness
- Palpitations
- Gastrointestinal intolerance
- Feeling hot
- Weight gain
Pharmacological properties
Mechanism of action (pharmacodynamics)
Betahistine attacks, among other things, the histamine H 1 receptors in the inner ear, where it has a vasodilatory effect. In addition, the excitation of nerve cells in the equilibrium nuclei is inhibited, which, together with the improved blood flow, has been claimed to have a positive effect on the symptoms mentioned above.
Bioavailability and metabolism
The absorption of betahistine is rapid and complete. Betahistine cannot be detected in the blood, but its inactive metabolite 2-pyridyl acetic acid is. Its maximum plasma level is reached after about half an hour, after 24 hours the substance is completely excreted in the urine.
toxicology
The following information on the LD 50 value (acute toxicity) is known:
Betahistine dimesylate
- Rat: 3030 mg / kg body weight orally, 604 mg / kg body weight iv
Betahistine dihydrochloride
- Rat: 3000 mg / kg body weight orally, 505 mg / kg body weight iv
- Dog: 129 mg / kg body weight iv
No proven effect on diseases of the inner ear
Meniere's disease
In 2001 the Cochrane Collaboration , an international organization for the investigation of medical therapies, published a systematic review (meta-study) on the effect of betahistine in Meniere's disease. For the period 1962–1999 there were only six randomized controlled studies with a total of 162 patients on this question . The analysis of this work showed that there was insufficient data to be able to judge whether betahistine has any effect on Meniere's disease at all. In 2016, the largest placebo-controlled double-blind study to date on 221 showed that neither the previous maximum dose of 48 mg / d nor 144 mg / d is superior to placebo. C. Adrion, CS Fischer, J. Wagner, R. Gürkov, U. Mansmann, M. Strupp: Efficacy and safety of betahistine treatment in patients with Meniere's disease: primary results of a long term, multicentre, double blind, randomized, placebo controlled, dose defining trial (BEMED trial). In: BMJ (Clinical research ed.). Volume 352, 2016, p. H6816. PMID 26797774, PMC 4721211 (free full text)., With which the ineffectiveness is proven to be at least three times the maximum dose previously permitted.
Hydrops cochleae
In the case of hydrops cochleae (also endolymphatic hydrops), as a preceding and accompanying symptom of Meniere's disease, the situation is similar. After the expansion of the endolymph-filled vessels in the inner ear was quantitatively measurable in humans using magnetic resonance imaging (MRI) in recent years , a study with six patients showed an effect of betahistine in none of them and a case study of one patient over two years showed an end to it Spells of dizziness but worsening of hydrops and hearing in both ears.
Trade names
Aequamen (D), Betaserc (A, CH), Betavert (D), Vasomotal (D), numerous generics
Individual evidence
- ↑ a b c d Datasheet Betahistin from Sigma-Aldrich , accessed on March 13, 2011 ( PDF ).
- ↑ a b c Entry on Betahistine. In: Römpp Online . Georg Thieme Verlag, accessed on June 27, 2019.
- ↑ Mutschler, Ernst: Mutschler drug effects. Pharmacology, clinical pharmacology, toxicology. 10th edition. Stuttgart. 2013.
- ^ Claes, J .: A Review of Medical Treatment for Ménières Desease . In: Acta Oto-Laryngologica 120, No. 8, 2000, doi: 10.1080 / 000164800750044461 , pp. 34-39
- ↑ a b c Fachinformationenen Aequamen ®
- ↑ specialist Informationenen Vasomotal ®
- ↑ a b Betahistin In: HagerRom 2006 , Springer Medizin Verlag
- ↑ AL James, MJ Burton: Betahistine for Menière's disease or syndrome. In: The Cochrane database of systematic reviews. Number 1, 2001, S. CD001873, doi: 10.1002 / 14651858.CD001873 , PMID 11279734 (Review).
- ↑ R. Gürkov, W. Flatz, D. Keeser, M. Strupp, B. Ertl-Wagner, E. Krause: Effect of standard-dose Betahistine on endolymphatic hydrops: an MRI study pilot. In: European archives of oto-rhino-laryngology: official journal of the European Federation of Oto-Rhino-Laryngological Societies (EUFOS): affiliated with the German Society for Oto-Rhino-Laryngology - Head and Neck Surgery. Volume 270, Number 4, March 2013, pp. 1231-1235, doi: 10.1007 / s00405-012-2087-3 , PMID 22760844 .
- ↑ C. Jerin, E. Krause, B. Ertl-Wagner, R. Gürkov: Longitudinal assessment of endolymphatic hydrops with contrast-enhanced magnetic resonance imaging of the labyrinth. In: Otology & neurotology: official publication of the American Otological Society, American Neurotology Society [and] European Academy of Otology and Neurotology. Volume 35, Number 5, June 2014, pp. 880-883, doi: 10.1097 / MAO.0000000000000393 , PMID 24770407 .
C. Adrion, CS Fischer, J. Wagner, R. Gürkov, U. Mansmann, M. Strupp: Efficacy and safety of betahistine treatment in patients with Meniere's disease: primary results of a long term, multicentre, double blind, randomized, placebo controlled, dose defining trial (BEMED trial). In: BMJ (Clinical research ed.). Volume 352, 2016, p. H6816. PMID 26797774, PMC 4721211 (free full text).
