Pain Relieving Spray

Abstract

A pain relieving aerosol spray (pain relieving and pain preventing aerosol spray) comprising a pain relieving composition and at least one refrigerant, wherein the pain relieving aerosol spray is capable of providing rapid onset local anaesthesia of intact skin and/or a wound of a subject to which it is applied and further pain relief due to the pain relieving composition remaining on the wound of the subject. The pain relieving composition comprises a liquid gel matrix that contains at least one anaesthetic agent, a vasoconstrictor, and an antiseptic agent. The spray can be used for a surgical procedure or animal husbandry procedure, such as castration or branding, or treating a burn or wound.

Claims

1-20. (canceled)

21. A method selected from the group consisting of: (a) cooling intact skin and/or a wound of a subject for pain relief and/or pain prevention; (b) providing a subject with pain relief and/or pain prevention; (c) providing a subject with rapid onset local anaesthesia and further pain relief; and (d) providing a subject with rapid onset local anaesthesia immediately prior to carrying out a surgical step or animal husbandry step on the subject that produces a wound, said method comprising the step of applying a pain relieving and pain preventing aerosol spray onto intact skin and/or wound of the subject, wherein said aerosol spray comprises a pain relieving composition and at least one refrigerant, and wherein the aerosol spray provides rapid onset local anaesthesia of intact skin and/or a wound of the subject to which it is applied due to the at least one refrigerant and further pain relief due to the pain relieving composition remaining on the wound of the subject.

22. The method of claim 21, wherein the aerosol spray or pain relieving composition has at least one property selected from the group consisting of: the aerosol spray or pain relieving composition is in the form of a liquid prior to having been applied to skin or a wound; the aerosol spray or pain relieving composition forms, or is in the form of, a sticky, viscous, adhesive gel when applied to skin or a wound; the aerosol spray or pain relieving composition is in the form of a liquid that thickens to an adhesive gel when reacting with physiological fluids of a wound; and the aerosol spray or pain relieving composition forms an effective long-lasting barrier over skin or a wound.

23. The method of claim 21, wherein the pain relieving composition comprises a liquid gel matrix that contains the following: at least one anaesthetic agent; a vasoconstrictor; and an antiseptic agent, and the pain relieving composition is optionally coloured.

24. The method of claim 21, wherein the pain relieving composition comprises a liquid gel matrix that contains ingredients selected from the group consisting of: lidocaine, adrenaline and cetrimide, and the pain relieving composition is optionally coloured; tetracaine, adrenalin and cetrimide, and the pain relieving composition is optionally coloured; and lidocaine, bupivacaine, adrenalin and cetrimide, and the pain relieving composition is optionally coloured, wherein said pain relieving composition has a pH lower than about 4.0.

25. The method of claim 21, wherein the pain relieving composition comprises a composition selected from the group consisting of: (a) Composition 1 comprising: about 100 mg/ml non-crystallising liquid sorbitol (70%); about 50.0 mg/ml lignocaine HCl; about 5.0 mg/ml bupivacaine HCl; about 1.5 mg/ml sodium metabisulfite; about 5.0 mg/ml cetrimide; about 45.0 μg/ml adrenaline tartrate; about 5.0 mg/ml hydroxy cellulose; and optionally colourant; (b) Composition 2 whereby lignocaine of Composition 1 is replaced by tetracaine at about 10 mg/ml-100 mg/ml; (c) Composition 3 comprising: about 100 mg/ml non-crystallising liquid sorbitol (70%); about 40.0 mg/ml lignocaine HCl; about 1.5 mg/ml sodium metabisulfite; about 5.0 mg/ml cetrimide; about 36.0 μg/ml adrenaline tartrate; about 5.0 mg/ml hydroxy cellulose; and optionally colourant; (d) Composition 4 whereby lignocaine of Composition 3 is replaced by tetracaine at about 10 mg/ml-100 mg/ml; (e) Composition 5 comprising: about 100.0 mg/ml non-crystallising liquid sorbitol (70%); about 50.0 mg/ml (5%) tetracaine HCl; about 1.5 mg/ml sodium metabisulfite; about 5.0 mg/ml cetrimide; about 45.0 μg/ml adrenaline tartrate; about 5.0 mg/ml hydroxy cellulose; and optionally colourant; (f) Composition 6 comprising: lignocaine, bupivacaine, adrenaline, cetrimide, 2-ethyl hydroxycellulose, sodium metabisulfite, liquid sorbitol (70%), buffer, and, optionally colourant; (g) Composition 7 whereby lignocaine of Composition 6 is replaced by tetracaine at about 10 mg/ml-100 mg/ml; (h) Composition 8 comprising: amethocaine/tetracaine, adrenaline, cetrimide, 2-ethyl hydroxycellulose, sodium metabisulfite, liquid sorbitol (70%), buffer, and, optionally, colourant; (i) Composition 9 comprising a liquid gel matrix that contains the following: lidocaine, adrenalin, and cetrimide, and the composition is optionally coloured, wherein said composition has a pH lower than about 4.0; (j) Composition 10 comprising a liquid gel matrix that contains the following: tetracaine, adrenalin, and cetrimide, and the composition is optionally coloured, wherein said composition has a pH lower than about 4.0; or (k) Composition 11 comprising a liquid gel matrix that contains the following: lidocaine, bupivacaine, adrenalin, and cetrimide, and the composition is optionally coloured, wherein said composition has a pH lower than about 4.0; (l) Composition 12 comprising: about 0.5% w/v cetrimide; about 0.5% w/v hydroxyethylcellulose; about 5% w/v tetracaine HCl; about 0.15% w/v sodium metabisulfite; about 0.00495% w/v adrenaline tartrate; about 10% w/v sorbitol 70%; and optionally dye/colourant; and (m) Composition 13 comprising: about 0.5% w/v cetrimide; about 0.5% w/v hydroxyethylcellulose; about 1% w/v tetracaine HCl; about 0.15% w/v sodium metabisulfite; about 0.00495% w/v adrenaline acid tartrate; about 10% w/v sorbitol 70%; and optionally dye/colourant.

26. The method of claim 21, wherein the at least one refrigerant comprises at least one of the following selected from the group consisting of: a compressed gas; a liquefied hydrocarbon; a fluorinated hydrocarbon; an ether; and, a hydrofluoroalkane.

27. The method of claim 21, wherein the aerosol spray is in a form selected from the group consisting of: a sprayable stream; a sprayable mist; and, a sprayable foam.

28. The method of claim 21, wherein the aerosol spray comprises or is delivered from a pressurised spray container, and comprises at least one propellant.

29. The method of claim 28, wherein the at least one refrigerant and the at least one propellant are one and the same.

30. The method of claim 28, wherein the pain relieving composition is in the form of a liquid that is expelled from the pressurised spray container as a foam and sets as a sticky viscous gel when exposed to the skin or wound, after the at least one refrigerant evaporates or otherwise dissipates.

31. The method of claim 28, wherein the pressurised spray container comprises a delivery nozzle, cap, tip or actuator.

32. The method of claim 31, wherein the delivery nozzle is in the form of a needle cap.

33. The method of claim 21, wherein the aerosol spray is applied to the subject for between about 1 and 10 seconds, and cools the skin or wound of the subject to a temperature from about −20° C. to about 10° C.

34. The method of claim 28, comprising properties selected from the group consisting of: (a) the aerosol spray comprises a 50% w/w butane and propane blend, and 20-50% w/w pain relieving composition; the aerosol spray is delivered from a pressurised spray container comprising a delivery nozzle in the form of a needle cap; and the aerosol spray is delivered as a sticky long-lasting foam with substantially no run-off from the wound; (b) the aerosol spray comprises a 50% w/w butane, propane and isobutane blend, and 20-50% w/w pain relieving composition; the aerosol spray is delivered from a pressurised spray container comprising a delivery nozzle in the form of a needle cap; and the aerosol spray is delivered as a sticky long-lasting foam with substantially no run-off from the wound; (c) the aerosol spray comprises 50% w/w dimethyl ether, and 20-50% w/w pain relieving composition; the aerosol spray is delivered from a pressurised spray container comprising a delivery nozzle in the form of a needle cap; and the aerosol spray is delivered as a sticky long-lasting foam with substantially no run-off from the wound; (d) the aerosol spray comprises 70% w/w dimethyl ether, and 10-30% w/w pain relieving composition; and, the aerosol spray is delivered from a pressurised spray container comprising a delivery nozzle in the form of a needle cap; and (e) the aerosol spray comprises 80% w/w dimethyl ether, and 10-20% w/w pain relieving composition; and, the aerosol spray is delivered from a pressurised spray container comprising a delivery nozzle in the form of a needle cap.

35. The method of claim 21, wherein the surgical step or animal husbandry step of (d) is selected from the group consisting of: castration; mulesing; shearing; ear tagging; branding; hot branding; dehorning; hot dehorning; dis-budding; marking; treating a wound; and, treating a burn.

36. A pain relieving and pain preventing aerosol spray comprising a pain relieving composition and at least one refrigerant, wherein the aerosol spray is formulated to provide rapid onset local anaesthesia of intact skin and/or a wound of a subject to which it is applied and further pain relief due to the pain relieving composition remaining on the wound of the subject.

37. The aerosol spray of claim 36, wherein the pain relieving composition comprises a liquid gel matrix that contains ingredients selected from the group consisting of: lidocaine, adrenaline and cetrimide, and the pain relieving composition is optionally coloured; tetracaine, adrenalin and cetrimide, and the pain relieving composition is optionally coloured; and lidocaine, bupivacaine, adrenalin and cetrimide, and the pain relieving composition is optionally coloured, wherein said pain relieving composition has a pH lower than about 4.0.

38. The aerosol spray of claim 36, wherein the pain relieving composition comprises a composition selected from the group consisting of: (a) Composition 1 comprising: about 100 mg/ml non-crystallising liquid sorbitol (70%); about 50.0 mg/ml lignocaine HCl; about 5.0 mg/ml bupivacaine HCl; about 1.5 mg/ml sodium metabisulfite; about 5.0 mg/ml cetrimide; about 45.0 μg/ml adrenaline tartrate; about 5.0 mg/ml hydroxy cellulose; and optionally colourant; (b) Composition 2 whereby lignocaine of Composition 1 is replaced by tetracaine at about 10 mg/ml-100 mg/ml; (c) Composition 3 comprising: about 100 mg/ml non-crystallising liquid sorbitol (70%); about 40.0 mg/ml lignocaine HCl; about 1.5 mg/ml sodium metabisulfite; about 5.0 mg/ml cetrimide; about 36.0 μg/ml adrenaline tartrate; about 5.0 mg/ml hydroxy cellulose; and optionally colourant; (d) Composition 4 whereby lignocaine of Composition 3 is replaced by tetracaine at about 10 mg/ml-100 mg/ml; (e) Composition 5 comprising: about 100.0 mg/ml non-crystallising liquid sorbitol (70%); about 50.0 mg/ml (5%) tetracaine HCl; about 1.5 mg/ml sodium metabisulfite; about 5.0 mg/ml cetrimide; about 45.0 m/ml adrenaline tartrate; about 5.0 mg/ml hydroxy cellulose; and optionally colourant; (f) Composition 6 comprising: lignocaine, bupivacaine, adrenaline, cetrimide, 2-ethyl hydroxycellulose, sodium metabisulfite, liquid sorbitol (70%), buffer, and, optionally colourant; (g) Composition 7 whereby lignocaine of Composition 6 is replaced by tetracaine at about 10 mg/ml-100 mg/ml; (h) Composition 8 comprising: amethocaine/tetracaine, adrenaline, cetrimide, 2-ethyl hydroxycellulose, sodium metabisulfite, liquid sorbitol (70%), buffer, and, optionally, colourant; (i) Composition 9 comprising a liquid gel matrix that contains the following: lidocaine; adrenalin; and cetrimide, and the composition is optionally coloured, wherein said composition has a pH lower than about 4.0; (j) Composition 10 comprising a liquid gel matrix that contains the following: tetracaine; adrenalin; and cetrimide, and the composition is optionally coloured, wherein said composition has a pH lower than about 4.0; or (k) Composition 11 comprising a liquid gel matrix that contains the following: lidocaine; bupivacaine; adrenalin; and cetrimide, and the composition is optionally coloured, wherein said composition has a pH lower than about 4.0; (l) Composition 12 comprising: about 0.5% w/v cetrimide; about 0.5% w/v hydroxyethylcellulose; about 5% w/v tetracaine HCl; about 0.15% w/v sodium metabisulfite; about 0.00495% w/v adrenaline tartrate; about 10% w/v sorbitol 70%; and optionally dye/colourant; and (m) Composition 13 comprising: about 0.5% w/v cetrimide; about 0.5% w/v hydroxyethylcellulose; about 1% w/v tetracaine HCl; about 0.15% w/v sodium metabisulfite; about 0.00495% w/v adrenaline acid tartrate; about 10% w/v sorbitol 70%; and optionally dye/colourant.

39. The aerosol spray of claim 36, wherein the at least one refrigerant comprises at least one of the following ingredients selected from the group consisting of: a compressed gas; a liquefied hydrocarbon; a fluorinated hydrocarbon; an ether; and, a hydrofluoroalkane.

40. The aerosol spray of claim 36, comprising properties selected from the group consisting of: (a) the aerosol spray comprises a 50% w/w butane and propane blend, and 20-50% w/w pain relieving composition; and, the aerosol spray forms a sticky long-lasting foam with substantially no run-off from the wound; (b) the aerosol spray comprises a 50% w/w butane, propane and isobutane blend, and 20-50% w/w pain relieving composition; and, the aerosol spray forms a sticky long-lasting foam with substantially no run-off from the wound; (c) the aerosol spray comprises 50% w/w dimethyl ether, and 20-50% w/w pain relieving composition; and, the aerosol spray forms a sticky long-lasting foam with substantially no run-off from the wound; (d) the aerosol spray comprises 70% w/w dimethyl ether, and 10-30% w/w pain relieving composition; and (e) the aerosol spray comprises 80% w/w dimethyl ether, and 10-20% w/w pain relieving composition.

Description

DESCRIPTION OF THE FIGURES

[0167] FIG. 1 shows various nozzles and caps for an aerosol can, for delivering the aerosol spray.

DESCRIPTION OF PREFERRED EMBODIMENTS

Example 1—Formulation of a Pain Relieving Composition Having a Long Duration of Action

[0168] This Example describes the preparation of a particularly preferred topical analgesic pain relieving composition. The composition is in the form of a gel that provides a prolonged analgesic effect. The composition has the following formulation:

TABLE-US-00003 Sorbitol Liquid 70% Non-Crystallising 100.0 mg/mL Lignocaine HCl 50.0 mg/mL (5%) Bupivacaine HCl 5.0 mg/mL (0.5%) Sodium Metabisulfite 1.5 mg/mL Cetrimide 5.0 mg/mL Adrenaline Tartrate 45.0 μg/mL Hydroxy Cellulose 5.0 mg/mL Purified water to 1 mL Optional: Food Dye (e.g. brilliant blue) Quantity to suit (q.s.)

[0169] The composition is prepared by combining/blending the above ingredients to achieve the required consistency.

[0170] If desired, the composition can further comprise an anti-inflammatory agent (e.g. meloxicam or carprofen), and/or an insecticide/insect repellent such as diazinon, spinosad or cyromazine (at about 1 mg/mL), and/or a skin penetrating enhancer, and/or a bittering agent.

Example 2—Formulation of a Pain Relieving Composition

[0171] This Example describes the preparation of another preferred pain relieving composition. The composition is in most respects the same as the composition of Example 1, except that it excludes bupivacaine. The composition has the following formulation:

TABLE-US-00004 Sorbitol Liquid 70% Non-Crystallising 100.0 mg/mL Lignocaine HCl 40.0 mg/mL (4%) Sodium Metabisulfite 1.5 mg/mL Cetrimide 5.0 mg/mL Adrenaline Tartrate 36.0 μg/mL (1:2000) Hydroxy Cellulose q.s. Purified water to 1 mL Optionally: Food Dye (e.g. blue) q.s.

[0172] The composition is prepared by combining/blending the above ingredients to achieve the required consistency.

[0173] If desired, the composition can further comprise an anti-inflammatory agent (e.g. meloxicam or carprofen), and/or an insecticide/insect repellent such as diazinon, spinosad or cyromazine (at about 1 mg/mL), and/or a skin penetrating enhancer, and/or a bittering agent.

Example 3—Formulation of a Pain Relieving Composition

[0174] This Example describes the preparation of another preferred pain relieving composition having only tetracaine as the anaesthetic agent. The composition has the following formulation:

TABLE-US-00005 Ingredient % w/v g/500 mL Water ~87 ~435 Cetrimide ~0.5 ~2.5 Hydroxyethylcellulose ~0.5 ~2.5 Tetracaine HCl ~5 ~25.2 Sodium metabisulfite ~0.15 ~0.75 Adrenaline acid tartrate ~0.00495 ~0.025 Sorbitol 70% ~10 ~50 Dye ~0.005 ~0.025 Final pH 4.0

[0175] The composition is prepared by combining/blending the above ingredients to achieve the required consistency.

[0176] If desired, the composition can further comprise an anti-inflammatory agent (e.g. meloxicam or carprofen), and/or an insecticide/insect repellent such as diazinon, spinosad or cyromazine (at about 1 mg/mL), and/or a skin penetrating enhancer, and/or a bittering agent.

Example 4—Formulation of a Pain Relieving Composition

[0177] This Example describes the preparation of another preferred pain relieving composition. The composition is in most respects the same as the composition of Example 3. The composition has the following formulation:

TABLE-US-00006 Ingredient % w/v g/500 mL Water ~90 ~450 Cetrimide ~0.50 ~2.5 Hydroxyethylcellulose ~0.5 ~2.5 Tetracaine HCl ~1 ~10.1 Sodium metabisulfite ~0.15 ~0.75 Adrenaline acid tartrate ~0.00495 ~0.025 Sorbitol 70% ~10 ~50 Dye ~0.005 ~0.025 Required a small amount of citric acid to adjust the pH to about 4.0.

[0178] The composition is prepared by combining/blending the above ingredients to achieve the required consistency.

[0179] If desired, the composition can further comprise an anti-inflammatory agent (e.g. meloxicam or carprofen), and/or an insecticide/insect repellent such as diazinon, spinosad or cyromazine (at about 1 mg/mL), and/or a skin penetrating enhancer, and/or a bittering agent.

Example 5—Formulation of a Topical Anaesthetic Crème Having a Long Duration of Action

[0180] This Example describes the preparation of another topical pain relieving composition in the form of a crème. The composition has the following formulation:

TABLE-US-00007 Cetyl Alcohol 78.00 mg/mL Paraffin Wax 135.00 mg/mL  Glycerol 75.00 mg/mL Lauryl Sulfate 10.00 mg/ml  Lignocaine HCl 50.00 mg/mL Bupivacaine HCl  5.00 mg/mL Sodium Metabisulfite  1.50 mg/mL Cetrimide  5.00 mg/mL Hydrochloric Acid 25% q.s. Adrenaline Acid Tartare 0.045 mg/mL Purified Water to 1 mL

[0181] The composition is prepared by combining the above ingredients to achieve the required consistency as required. The composition is in the form of a “sticky” crème.

[0182] If desired, the composition can further comprise an anti-inflammatory agent, and/or an insecticide/insect repellent, and/or a skin penetrating enhancer, and/or a bittering agent.

Example 6—Formulation of a Topical Anaesthetic Gel Having a Long Duration of Action

[0183] This example describes the preparation of another topical anaesthetic composition having a gum base. The composition has the following formulation:

TABLE-US-00008 Xanthum Gum 10.00 mg/mL  Gum Arabic 1.00 mg/mL Sorbitol Liquid 100.00 mg/mL  Lignocaine HCl 50.00 mg/mL  Bupivacaine HCl 5.00 mg/mL Sodium Metabisulfite 1.50 mg/mL Cetrimide 5.00 mg/mL Hydrochloric Acid 25% q.s. Adrenaline Acid Tartare 0.045 mg/mL  Purified Water to 1 mL Optional: Dye q.s.

[0184] The composition is prepared by combining the above ingredients to achieve the required consistency. The composition is in the form of a “sticky” gel.

[0185] If desired, the composition can further comprise an anti-inflammatory agent, and/or an insecticide/insect repellent, and/or a skin penetrating enhancer, and/or a bittering agent.

Example 7—Formulation of a Topical Anaesthetic Gel Having a Long Duration of Action

[0186] This Example describes the preparation of another topical anaesthetic composition having a polyacrylic acid base. The composition has the following formulation:

TABLE-US-00009 Polyacrylic Acid 10.00 mg/mL Sodium Hydroxide q.s. Polyhydrogenated Castor Oil 10.00 mg/mL Sorbitol Liquid 100.00 mg/mL  Lignocaine HCl 50.00 mg/mL Bupivacaine HCl  5.00 mg/mL Sodium Metabisulfite  1.50 mg/mL Cetrimide  5.00 mg/mL Hydrochloric Acid 25% q.s. Adrenaline Acid Tartare 0.045 mg/mL Purified Water to 1 mL Optional: Dye q.s.

[0187] The composition is prepared by combining the above ingredients to achieve the required consistency. The composition is in the form of a “sticky” gel.

[0188] If desired, the composition can further comprise an anti-inflammatory agent, and/or an insecticide/insect repellent, and/or a skin penetrating enhancer, and/or a bittering agent.

Example 8—Formulation of a Topical Anaesthetic Gel Having an Insecticide and a Skin Penetrating Enhancer

[0189] This Example describes the preparation of another topical anaesthetic composition in the form of a spray-on gel having an insecticide (spinosad) as well as a skin penetrating enhancer (propylene glycol). The composition has the following formulation:

TABLE-US-00010 Cellulose 5.00 mg/mL Spinosad 1.25 mg/mL Propylene Glycol 100.00 mg/mL  Sorbitol Liquid 50.00 mg/mL  Lignocaine HCl 50.00 mg/mL  Bupivacaine HCl 5.00 mg/mL Sodium Metabisulfite 1.50 mg/mL Cetrimide 5.00 mg/mL Hydrochloric Acid 25% q.s. Adrenaline Acid Tartare 0.045 mg/mL  Purified Water to 1 mL Optional: Dye q.s.

[0190] The composition is prepared by combining the above ingredients to achieve the required consistency. The composition is in the form of a “sticky” gel”.

[0191] If desired, the composition can further comprise an anti-inflammatory agent, and/or a bittering agent.

Example 9—Preparation of Aerosol Sprays Utilising Carbon Dioxide as the Refrigerant and Propellant

[0192] This Example describes the preparation of aerosol sprays comprising the pain relieving composition of any one of Examples 1 to 8 in combination with carbon dioxide as the refrigerant/propellant.

[0193] An aerosol container is partially filled with the pain relieving composition of any one of Examples 1 to 8. The container is then sealed and charged with carbon dioxide until suitably pressurised. The carbon dioxide serves both as a refrigerant and propellant. The container's composition comprises 20-50% pain relieving composition (weight/weight) and carbon dioxide to balance.

[0194] Pressing an actuator button opens a valve of the container such that pressurised carbon dioxide can force the pain relieving composition up a dip tube of the container and through the valve and cap/nozzle. The pain relieving composition can be applied as an aerosol mist or foam depending on the final composition. A specially articulated spray nozzle (eg. needle cap) can also be used, if required, to help produce a long-lasting foam.

Example 10—Preparation of Aerosol Sprays Utilising Liquified Hydrocarbon or Dimethyl Ether as the Refrigerant and Propellant

[0195] An aerosol container is partially filled with the pain relieving composition of any one of Examples 1 to 8. The container is then sealed and charged with hydrocarbon until suitably pressurised. The hydrocarbon serves both as a refrigerant and propellant. The container's composition comprises 20 to 50% pain relieving composition (weight/weight) and 50-80% w/w butane and propane blend, butane, propane and isobutane blend, or dimethyl ether.

[0196] Preferred formulations and properties are shown in Table 1 below.

TABLE-US-00011 Pain Relieving Formulation Refrigerant/Propellant Composition Cap/Nozzle No. (% w/w) (% w/w) Type Comments/Properties 1 Butane and propane blend Examples 1 to 4 Needle cap Delivered as sticky 50 20-50 long-lasting foam with substantially no run-off from the wound. 2 Butane, propane and Examples 1 to 4 Needle cap Delivered as sticky isobutane blend 20-50 long-lasting foam 50 with substantially no run-off from the wound 3 Dimethyl ether Examples 1 to 4 Needle cap Delivered as sticky 50 20-50 short-lived foam with substantially no run- off from the wound 4 Dimethyl ether Examples 1 to 4 Needle cap 70 10-30 5 Dimethyl ether Examples 1 to 4 Needle cap 80 10-20

[0197] Pressing an actuator button opens a valve of the container such that pressurised propellant can force the pain relieving composition up a dip tube of the container and through the valve and cap/nozzle. The pain relieving composition is best applied as a chilled long-lasting foam.

Example 11—Use of the Pain Relieving Aerosol Sprays

[0198] The aerosol spray of Example 9 or 10 can be used to provide topical anaesthesia of intact skin, to numb it prior to a surgical or animal husbandry procedure (eg. castration). Topical anaesthetic agents, such as lidocaine or tetracaine, usually take 20-30 minutes to work on intact skin, whereas when cooled the “cryo-anaesthetic effect” of the cooling provides rapid skin anaesthesia within seconds—allowing the skin to be surgically cut—although the cryo-anaesthetic effect wears off quickly (within a minute or two). However, then the local anaesthetic agent/s can act on the cut nerve fibres to prolong an anaesthetic effect in the open wound (eg. for castration).

[0199] In practice, the aerosol spray of Example 9 or 10 is sprayed onto a (human or animal) subject's skin or wound, usually as a long-lasting foam, for the required period of time so as to elicit instant cooling/chilling and hence a local anaesthetic effect. Although the refrigerant dissipates and the foam breaks down, the pain relieving composition forms a film over the wound and remains to provide prolonged pain relief.

[0200] The aerosol spray is particularly suitable for treating wounds caused by hot branding and hot dehorning.

[0201] The aerosol spray is particularly suitable for treating wounds caused by castration.

[0202] Advantages of the present invention as exemplified include:

[0203] The aerosol spray can be easily applied to a subject, such as an animal.

[0204] The aerosol spray can be easily applied to a large number of animals in a short period of time.

[0205] Pain relief can be provided without injection or other invasive technique.

[0206] The aerosol spray provides an initial cooling effect and almost instant pain relief.

[0207] A single application can provide both rapid and long-lasting pain relief.

[0208] The aerosol spray foam is tenacious and will stick to the wound.

[0209] The aerosol spray foam is long lasting.

[0210] Successful application of the aerosol spray is easily assessable in that a large bead of foam can be seen covering the wound.

[0211] There is very little to no run-off of the foam from the wound.

[0212] The foam breaks down to leave a pain relieving composition film over the wound.

[0213] Throughout this specification, unless in the context of usage an alternative interpretation is required, the term “comprise” (and variants thereof such as “comprising” and “comprised”) denotes the inclusion of a stated integer or integers but does not exclude the presence of another integer or other integers.

[0214] Any reference to publications cited in this specification is not an admission that the disclosures constitute common general knowledge in Australia or in other countries.

[0215] It will be appreciated by one of skill in the art that many changes can be made to the composition and uses exemplified above without departing from the broad ambit and scope of the invention.