Analgesic compositions

1. A monophasic composition comprising a halogenated volatile compound and at least one component selected from the group consisting of 2-(2-ethoxyethoxy)-ethanol, hydroxypropyl cellulose (HPC) and a monoester of a (methyl vinyl ether-maleic acid) co-polymer;

wherein the composition further comprises at least one selected from the group consisting of an alcohol; a polyol; an organic solvent; an organic carbonate; a fatty acid or a salt thereof; a polyethylene glycol (PEG); a polypropylene glycol (PPG); a copolymer of 2-(2-hydroxypropoxy)propan-1-ol (PPG-12) and 1-methylene bis-4-isocyanatocyclohexane (SMDI); a poloxamer; saccharine; and any combinations thereof;

wherein the halogenated volatile compound is selected from the group consisting of isoflurane, halothane, enflurane, sevoflurane, desflurane, methoxyflurane, and any mixtures thereof,

wherein the polyol is selected from the group consisting of ethylene glycol, propylene glycol, glycerol, and any mixtures thereof,

wherein the organic solvent is selected from the group consisting of dimethylsulfoxide (DMSO), dimethylisosorbide, and any mixtures thereof, and

wherein the organic carbonate is selected from the group consisting of propylene carbonate, ethylene carbonate and any mixtures thereof.

2. The composition of claim 1 , comprising about 5% to about 95% w/w halogenated volatile compound.

3. The composition of claim 2 , comprising about 50% to about 90% w/w halogenated volatile compound.

4. The composition of claim 1 , wherein the alcohol is selected from the group consisting of methanol, ethanol, n-propanol, isopropanol, n-butanol, sec-butanol, isobutanol, t-butanol, and any mixtures thereof.

5. The composition of claim 1 , comprising about 2% to about 20% w/w alcohol.

6. The composition of claim 5 , wherein the alcohol is ethanol and wherein the composition comprises a % w/w ethanol concentration selected from the group consisting of: about 8.25%, about 10%, about 10.5%, about 12.5%, about 14.25%, about 15%, and about 20% w/w.

7. The composition of claim 1 , comprising a % w/w 2-(2-ethoxyethoxy)-ethanol concentration selected from the group consisting of: about 5% and about 10% w/w.

8. The composition of claim 1 , comprising from about 5% to about 20.25% w/w polyol.

9. The composition of claim 8 , comprising a % w/w polyol concentration selected from the group consisting of: about 5%, about 8%, about 14.75%, about 15%, about 15.25% and about 20.25% w/w.

10. The composition of claim 1 , comprising from about 5% to about 50% w/w organic solvent.

11. The composition of claim 10 , comprising from about 10% to about 50% w/w organic solvent.

12. The composition of claim 1 , comprising about 2.5% w/w organic carbonate.

13. The composition of claim 1 , comprising from about 1% to about 5% w/w HPC.

14. The composition of claim 13 , comprising a % w/w HPC concentration selected from the group consisting of: about 1.75%, about 2%, about 2.25%, about 2.5%, and about 5% w/w.

15. The composition of claim 1 , wherein the fatty acid or salt thereof is selected from the group consisting of myristoleic acid, palmitoleic acid, sapienic acid, oleic acid, elaidic acid, vaccenic acid, linoleic acid, linoelaidic acid, α-linolenic acid, arachidonic acid, eicosapentaenoic acid, erucic acid, docosahexaenoic acid, caprylic acid, capric acid, lauric acid, myristic acid, palmitic acid, stearic acid, arachidic acid, behenic acid, lignoceric acid, cerotic acid, and any combinations thereof.

16. The composition of claim 1 , comprising from about 1% to about 5% w/w fatty acid or a salt thereof.

17. The composition of claim 16 , comprising about 3% w/w fatty acid or a salt thereof.

18. The composition of claim 1 , wherein the PEG is selected from the group consisting of PEG-200, PEG-300, PEG-400, PEG-600, PEG-[950-1,050], PEG-1,000, PEG-[1,300-1,600], PEG-[1,305-1,595], PEG-1,450, PEG-1,500, PEG-2,000, PEG-2,050, PEG-3,000, PEG-[3,000-3,700], PEG-3,350, PEG-4,000, PEG-4,600, PEG-6,000, PEG-8,000, PEG-10,000, PEG-12,000, PEG-20,000, PEG-35,000, and any mixtures thereof.

19. The composition of claim 1 , comprising from about 6% to about 78% w/w PEG.

20. The composition of claim 1 , comprising a % w/w PEG concentration selected from the group consisting of: about 6%, about 9%, about 10%, about 15%, about 18.25%, about 20%, about 20.5% and about 78%.

21. The composition of claim 1 , wherein the monoester of a (methyl vinyl ether-maleic acid) co-polymer is n-butyl, isopropyl, ethyl, or any mixtures thereof.

22. The composition of claim 1 , comprising from about 15% to about 20% w/w monoester of a (methyl vinyl ether-maleic acid) co-polymer.

23. The composition of claim 22 , comprising about 20% w/w monoester of a (methyl vinyl ether-maleic acid) co-polymer.

24. The composition of claim 1 , comprising from about 5% to about 15% w/w copolymer of PPG-12 and SMDI.

25. The composition of claim 24 , comprising about 10% w/w copolymer of PPG-12 and SMDI.

26. The composition of claim 1 , comprising about 2% w/w saccharine.

27. The composition of claim 1 , comprising about 15% to about 20% w/w PPG.

28. The composition of claim 1 , comprising from about 1% to about 5% w/w poloxamer.

29. The composition of claim 28 , wherein the poloxamer comprises poloxamer 188, poloxamer 407, and any mixtures thereof.

30. The composition of claim 1 , wherein the composition is selected from the group consisting of:

(a) about 28% w/w DMSO, about 10% w/w copolymer of PPG-12 and SMDI, about 2% w/w HPC, and about 60% w/w isoflurane;

(b) about 25% w/w DMSO, about 5% w/w HPC, and about 70% w/w isoflurane;

(c) about 3% w/w oleic acid, about 14.75% w/w propylene glycol, about 1.75% w/w HPC, about 20.5% w/w PEG-400, and about 60% w/w isoflurane;

(d) about 5% w/w propylene glycol, about 10% w/w ethanol, about 10% w/w 2-(2-ethoxyethoxy)ethanol, about 6% w/w PEG-3350, about 9% w/w PEG-400 and about 60° A w/w isoflurane;

(e) about 23% w/w DMSO, about 15% w/w PPG-400, about 2% w/w HPC, and about 60° A w/w isoflurane;

(f) about 8% w/w propylene glycol, about 2% w/w HPC, about 20% w/w isopropyl alcohol, and about 70% w/w isoflurane;

(g) about 38.25% w/w DMSO, about 1.75 w/w HPC, and about 60% w/w isoflurane;

(h) about 3% w/w oleic acid, about 15% w/w propylene glycol, about 14.25% w/w ethanol, about 1.75% w/w HPC, about 1% w/w poloxamer 407, about 5% w/w poloxamer 188, and about 60% w/w isoflurane;

(i) about 12.5% w/w ethanol, about 20% w/w Gantrez ES-435, about 2.5% w/w propylene carbonate, about 5% w/w 2-(2-ethoxyethoxy)ethanol, and about 60% w/w isoflurane;

(j) about 10.5% w/w ethanol, about 20% w/w Gantrez ES-435, about 2.5% w/w propylene carbonate, about 5% w/w 2-(2-ethoxyethoxy)ethanol, about 2% w/w HPC, and about 60% w/w isoflurane;

(k) about 35% w/w DMSO, about 5% w/w HPC, and about 60% w/w isoflurane;

(l) about 3% w/w oleic acid, about 15.25% w/w propylene glycol, about 10% w/w ethanol, about 1.75% w/w HPC, about 10% w/w PEG-400, and about 60% w/w isoflurane;

(m) about 15% w/w propylene carbonate, about 10% w/w 2-(2-ethoxyethoxy) ethanol, about 15% w/w PEG-400, and about 60% w/w isoflurane;

(n) about 10% w/w copolymer of PPG-12 and SMDI, about 8.25% w/w ethanol, about 20° A w/w Gantrez ES-435, about 1.75% w/w HPC, and about 60% w/w isoflurane;

(o) about 10% w/w DMSO, about 5% w/w HPC, and about 85% w/w isoflurane;

(p) about 20% w/w DMSO, about 5% w/w HPC, and about 75% w/w isoflurane;

(q) about 3% w/w oleic acid, about 14.75% w/w propylene glycol, about 2.25% w/w HPC, about 20% w/w PEG-400, and about 60% w/w isoflurane;

(r) about 3% w/w oleic acid, about 15% w/w propylene glycol, about 2% w/w HPC, about 20% w/w PEG-400, and about 60% w/w isoflurane;

(s) about 20% w/w Gantrez ES-435, about 1.75% w/w HPC, about 18.25% w/w PEG-400, and about 60% w/w isoflurane;

(t) about 18% w/w DMSO, about 20% w/w Gantrez ES-435, about 2% w/w HPC, and about 60% w/w isoflurane;

(u) about 5% w/w DMSO, about 5% w/w HPC, and about 90% w/w isoflurane;

(v) about 3% w/w oleic acid, about 10% w/w copolymer of PPG-12 and SMDI, about 15.25% w/w propylene glycol, about 10% w/w ethanol, about 1.75% w/w HPC, and about 60% w/w isoflurane;

(x) about 37.5% w/w DMSO, about 2.5% w/w HPC, and about 60% w/w isoflurane; and

(z) about 3% w/w oleic acid, about 20.25% w/w propylene glycol, about 15% w/w ethanol, about 1.75% w/w HPC, and about 60% w/w isoflurane.

31. The composition of claim 1 , wherein the composition is incorporated in a medical patch.