Moxonidine

Structural formula
General
Non-proprietary name	Moxonidine
other names	4-chloro- N - (4,5-dihydro-1 H -imidazol-2-yl) -6-methoxy-2-methylpyrimidine-5-amine
Molecular formula	C 9 H 12 ClN 5 O
External identifiers / databases
CAS number 75438-57-2 (free base) 75438-58-3 ( hydrochloride ) EC number 629-833-3 ECHA InfoCard 100.158.061 PubChem 4810 ChemSpider 4645 DrugBank DB09242 Wikidata Q419944
Drug information
ATC code	C02 AC05
Drug class	Antihypertensive drugs Antisympathotonics
Mechanism of action	Agonist at pre- and postsynaptic α 2 -adrenoceptors Agonist at imidazoline receptors
properties
Molar mass	241.68 g · mol -1
Melting point	217–219 ° C (free base) 189 ° C (hydrochloride)
safety instructions
Please note the exemption from the labeling requirement for drugs, medical devices, cosmetics, food and animal feed GHS labeling of hazardous substances danger H and P phrases H: 301-411 P: 273-264-301 + 310-321-405-501
Toxicological data	130 mg kg −1 ( LD 50 ,  rat ,  oral )
As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions .

Moxonidine is a medicine used to treat essential hypertension ( high blood pressure ). It is an analogue of the blood pressure lowering agent clonidine and is one of the imidazoline derivatives . The patent granted to Beiersdorf AG in 1980 has expired and moxonidine is now available as a generic drug .

pharmacology

Mechanism of action

The active ingredient penetrates due to its lipophilicity fast in the central nervous system (CNS) before and acts as an agonist at the postsynaptic α ₂ -adrenoceptors in the solitary tract nucleus , a switching of blood pressure regulation, whereby the sympathetic tone and thus the blood pressure is reduced. In addition, the peripheral presynaptic α ₂ -adrenoceptors are stimulated, which leads to a reduced release of noradrenaline . The strongest effect, concerning the antihypertensive effect, follows from the effect as an agonist on the imidazoline receptor , u. a. in the ventrolateral medulla oblongata , which is much more pronounced in moxonidine than in clonidine, and which in turn inhibits sympathetic activity.

application

Moxonidine is mainly used to treat essential arterial hypertension without a known cause, for which the substance is also approved. It is also used as an antihypertensive agent to relieve the symptoms of opiate withdrawal .

Pharmacokinetics

The active ingredient is quickly absorbed and quickly transported to the site of action in the central nervous system. The plasma half-life is approx. 2-3 hours and the subsequent elimination takes place renally (via the kidneys).

Side effects

The decrease in sympathetic tone can lead to dry mouth , drowsiness, hypotension , libido and erectile dysfunction. The double effect on the α ₂ - and imidazoline receptors is a retention of sodium - ions and thus a tendency for edema formation possible.

At the beginning of treatment there may be a sharp drop in blood pressure with dizziness and headache.

Sudden discontinuation must be avoided at all costs, as this can lead to a massive increase in blood pressure (blood pressure rebound ).

Interactions

The agonism of α ₂ -adrenoceptors increases the effect of neuroleptics , hypnotics and alcohol .

Contraindications

Due to the complex mechanism of action, there are numerous basic contraindications (selection):

• malignant arrhythmias
• Heart failure NYHA II-IV
• unstable angina pectoris
• Angioedema
• Pregnancy and breastfeeding

There are also a number of recommendations where the drug should not be used due to a lack of therapeutic experience and a possible potential for interaction (selection):

• Intermittent claudication (peripheral arterial disease)
• Raynaud's disease
• Parkinson's disease
• epileptic diseases
• glaucoma

Potency and dosage

Moxonidine is available in strengths of 0.2–0.3 and 0.4 mg and is used as standard at 0.2–0.4 mg per day, whereby it must be ensured that the maximum single dose is 0.4 mg and the total daily dose does not exceed 0.6 mg.

Trade names

Monopreparations

Cynt (D), Normohex (A), Physiotens (D, CH), numerous generics (D, A)

Individual evidence

1. ↑ ^{a b c d e f} Mutschler, Geisslinger, Kroemer, Ruth, Schäfer-Korting: Mutschler drug effects: textbook of pharmacology and toxicology , Wissenschaftliche Verlagsges. 9th edition, 2008, ISBN 3-8047-1952-X .
2. ↑ ^{a b} The Merck Index . An Encyclopaedia of Chemicals, Drugs and Biologicals. 14th edition, 2006, pp. 1087-1088, ISBN 978-0-911910-00-1 .
3. ↑ ^{a b} Moxonidine ( Memento from October 31, 2016 in the Internet Archive )
4. ↑ Data sheet MOXONIDINE CRS (PDF) at EDQM , accessed on July 28, 2008.
5. ↑ ^{a b c d e} ABDA database (as of July 28, 2008).

This article is about a health issue. It is not used for self-diagnosis and does not replace a diagnosis by a doctor. Please note the information on health issues !