Methoxyflurane

Structural formula
General
Non-proprietary name	Methoxyflurane
other names	2,2-dichloro-1,1-difluoro-1-methoxyethane ( IUPAC ) Methoxyfluranum ( Latin )
Molecular formula	C 3 H 4 Cl 2 F 2 O
Brief description	flammable, volatile, colorless liquid
External identifiers / databases
CAS number 76-38-0 EC number 200-956-0 ECHA InfoCard 100,000,870 PubChem 4116 DrugBank DB01028 Wikidata Q411594
Drug information
ATC code	N01 AB03
Drug class	Inhalation anesthetic
properties
Molar mass	164.97 g · mol -1
Physical state	liquid
density	1.44 g cm −3 (25 ° C)
Melting point	−35 ° C
boiling point	104.5 ° C (101.325 k Pa )
Vapor pressure	32 h Pa (at 20 ° C)
solubility	sparingly soluble in water (28.6 g l −1 at 37 ° C)
safety instructions
Please note the exemption from the labeling requirement for drugs, medical devices, cosmetics, food and animal feed GHS labeling of hazardous substances Caution H and P phrases H: 226-319-341 P: 210-280-303 + 361 + 353-305 + 351 + 338-405-501
Toxicological data	150 mg kg −1 ( LD 50 ,  mouse ,  iv ) 3600 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 .

Methoxyflurane is a chemical in the group of flurans . It was used as a penthrane from 1960 (by JF Artusio) to the 1970s as an inhalation anesthetic .

properties

Methoxyflurane is a flammable, volatile, colorless liquid that is sparingly soluble in water.

When methoxyflurane is broken down in the body, a particularly high concentration of inorganic fluoride is produced , which is said to have toxic effects on the kidneys. It is therefore no longer used clinically. In Australia, however, it is very common preclinically for short-term pain relief from traumatic injuries and is also used by non-medical personnel. The application is carried out via an inhaler of the because of its appearance as "green pipe" ( English Green Whistle ) is referred to. In 2018, methoxyflurane was again approved in this application form and under the name Penthrox in German-speaking countries.

With a minimum alveolar concentration of 0.16, it is very potent. The very high solubility in fat causes very slow draining and flooding, which is a disadvantage in anesthesia.

Physical data:

• Metabolism rate : 50%
• Minimum alveolar concentration : 0.16% atm
• Blood-gas partition coefficient : 12

safety instructions

The vapors of methoxyflurane can form an explosive mixture with air ( flash point 37 ° C). It is a nephrotoxin because it damages the kidney's concentration mechanism. Responsible for this is the fluoride ion produced during oxidative metabolism.

Web links

• Methoxyflurane Drug Information
• Entry on methoxyflurane at Vetpharm

Individual evidence

1. ↑ ^{a b c d e f g h i j} Entry on methoxyflurane in the GESTIS substance database of the IFA , accessed on February 1, 2016(JavaScript required) .
2. ↑ ^{a b} entry on methoxyflurane. In: Römpp Online . Georg Thieme Verlag, accessed on April 27, 2014.
3. ↑ M. Nuscheler et al.: Fluorine-induced nephrotoxicity: fact or fiction? In: Anaesthesiologist. 1996; 45, pp. 32-40.
4. ↑ P. Buntine, O. Thom, F. Babl, M. Bailey, S. Bernard: Prehospital analgesia in adults using inhaled methoxyflurane (subscription required) . In: Emergency Medicine Australasia . tape 19 , no. 6 , 2007, p. 509-514 , doi : 10.1111 / j.1742-6723.2007.01017.x , PMID 18021102 .
5. ↑ https://www.pharmawiki.ch/wiki/index.php?wiki=Methoxyfluran
6. ^ Gerhard Eisenbrand, Manfred Metzler, Frank J. Hennecke: Toxicology for Chemists. Georg Thieme Verlag, Stuttgart 1994, ISBN 3-13-127001-2 , p. 66.