GB2191093A

GB2191093A - Antiseptic compositions

Info

Publication number: GB2191093A
Application number: GB08712772A
Authority: GB
Inventors: William Graeme Bytheway; James Barlow Milnes
Original assignee: Beta Medical Products Ltd
Current assignee: Beta Medical Products Ltd
Priority date: 1986-06-04
Filing date: 1987-06-01
Publication date: 1987-12-09
Anticipated expiration: 2007-06-01
Also published as: GB2191093B; GB8712772D0; GB8613504D0

Abstract

Antiseptic aerosol spray compositions comprise finely divided povidone-iodine and finely divided lactose dispersed in liquid propellant.

Description

SPECIFICATION Antiseptic compositions This invention concerns antiseptic compositions containing, as active ingredient, povidone-iodine, which is a complex formed by reacting poly(1-vinylpyrrolidone)with elemental iodine.

Povidone-iodine is a remarkable substance in that it exhibits the antiseptic and germicidal activities of iodine without having the disadvantages of iodine. For example, solutions of pure iodine, when applied to in fact human skin, can irritate, stain and cause allergic reactions. By contrast povidone-iodine is non-irritant and non-sensitising.

Povidone-iodine is, therefore, a most useful antiseptic having the capacity to kill an extremely wide range of Gram positive and Gram negative bacteria, viruses, protozoa, yeasts and fungi. It is particularly useful as it car be employed for certain topical applications as an alternative to antibiotics, thereby reducing the risk of the useful life of the antibiotics being shortened due to the development of resistant strains of organisms.

Povidone-iodine is mainly formulated as an aqueous solution for application to the skin. There are, however, a number of applications where such formulations are unsuitable. For example, the use of an aqueous solution of povidone-iodine for the treatment or prevention of infection in areas of the body that are very wet, such as varicose ulcers which are exuding wet debris and pus, simply adds more unwanted liquid to the wound.

In first aid treatment of cuts or burns to the skin using an antiseptic, the presence of blood dilutes and interferes with aqueous solutions. Thus, there are many occasions when a dry powder preparation would be preferred.

Hitherto, the only method available of applying povidone-iodine as a dry powder has been from an aerosol spray, where the povidone-iodine has been suspended in pressurised fluorinated hydrocarbon aerosol propellants. When the aerosol is activated, the propellants (having a boiling point below 0 C) are exhausted to atmosphere in spray form. The powder is deposited at the site to which the spray is directed.

This method was thought to have a number of disadvantages mainly because of the use of propellants and so other proposals were made for applying povidone-iodine as a powder.

It is now believed that aerosol spray application of povidone-iodine may be desirable in some circumstances and the object of this invention is to provide an aerosol spray containing povidone-iodine.

According to the invention there is provided an aerosol spray composition comprising finely divided povidone-iodine and finely divided lactose dispersed in liquid propellant.

The lactose is present as a bulking agent for the povidone-iodine and has the following advantageous properties: 1. It is safe for use on human skin, whether intact or broken, and particularly in cuts to the skin.

2. It is inert to the presence of iodine, i.e. it does not react with povidone-iodine.

3. It is free-flowing and does not form agglomerates with povidone-iodine which has absorbed water but still remains in powder form.

The finely divided lactose used in the compositions of the invention advantageously has particle sizes of 5 tc 150 microns.

The compositions of the invention will preferably comprise 0.1 to 10% by weight of povidone-iodine and lactose combined and 90 to 99% by weight of propellant. The povidone-iodine/lactose combination will preferably contain 0.01 to 20% by weight of povidone-iodine. The povidone-iodine itself preferably contains from 9 to 12% available iodine and has a molecular weight not exceeding 35,000 + 5%.

The compositions of the invention may also contain other suitable constituents, such as zinc oxide. From a medical point of view zinc oxide posseses mild astringent and antiseptic properties and acts so as to aid the healing of skin wounds.

Any suitable propellant may be used and that may be a single substance or a mixture of substances.

Suitable propellants for use in the invention include chlorinated fluorinated hydrocarbons, hydrocarbons and dimethylether.

Examples of suitable chlorinated fluorinated hydrocarbons are trichiorofluoromethane, dichlorodifluoromethane and dichlorotetrafluoroethane. Examples of suitable hydrocarbons are butane, propane and isobutane.

Blends of propellant are probably preferred and the following blends are suitable: (a) Trichiorofluoromethane lotto 50% by weight Dichlorodifluoromethane 50 to 90% by weight (b) Dichlorotetrafluoroethane 40 to 80% by weight Dichlorotetrafluoroethane 20 to 60% by weight (c) Dichlorodifluoromethane 20 to 50% by weight Butane 50 to 80% by weight (d) Dichlorodifluoromethane 20 to 40% by weight Dimethyl ether 60 to 80% by weight The aerosol compositions of the invention may be made in the following way. Preferably under conditions that reduce or remove humidity, such as under a nitrogen atmosphere, finely divided povidone-iodine and lactose powders are added to a suitable liquid propellant and mixed by mechanical agitation so as to disperse the powders uniformly within the liquid propellant.This mixing is also preferably done in an atmosphere which excludes moisture, such as under nitrogen, as both powders, particularly povidone-iodine, are hygroscopic.

The resultant slurry is then dosed into sterile aerosol containers, preferably using a system that continuously recirculates, so as to maintain an uniform and homogeneous mixture. A previously sterilised aerosol valve is then inserted and sealed in place on the container and further propellant injected to make up the amount as desired. The further propellant has preferably been sterilised by passage through sterilising filters.

The original slurry and additional propellant can now be thoroughly mixed so that the aerosol spray is ready for use.

The aerosol spray of the invention has an advantage over previous povidone-iodine formulations in that a larger quantity of mixed powders can appear on the skin quickly and so prevent over-spraying and the risk of a cold burn from repellant liquid accumulating on the skin.

The invention will now be further described with reference to the following Example.

Example An aerosol spray was prepared in the following way. Firstly under an atmosphere of nitrogen a mixture of finely divided povidone-iodine (5% by weight) and lactose (95% by weight) was dispersed in trichlor ofluoromethane by mechanical agitation. The resultant slurry was dosed into a sterilised aerosol container, a valve inserted and the container pressurised by the injection of further sterilised trichlorofluoromethane with dichiorodifluoromethane to give a container content of approximately 5% by weight powder components and 95% by weight propellants.

Claims

1. An aerosol spray composition comprising finely divided povidone-iodine and finely divided lactose dispersed in liquid propellant.

2. A composition as claimed in claim 1, wherein the finely divided lactose has particle sizes of 5 to 150 microns.

3. A composition as claimed in claim 1 or 2, comprising 0.1 to 10% by weight of povidone-iodine and lactose combined and 90 to 99% by weight of propellant.

4. A composition as claimed in claim 1, 2 or 3, wherein the povidone-iodine/lactose combination contains 0.01 to 20% by weight of povidone-iodine.

5. A composition as claimed in any one of claims 1 to 4, wherein the povidone-iodine contains from 9 to 12% available iodine and has a molecular weight not exceeding 35,000 + 5%.

6. A composition as claimed in anyone of claims 1 to 5 also containing zinc oxide.

7. A composition as claimed in any one of claims 1 to 6, wherein the propellant is one or more of chlorinated fluorinated hydrocarbons, hydrocarbons and dimethylether.

8. A composition as claimed in claim 7, wherein the chlorinated fluorinated hydrocarbons are selected from trichiorofluoromethane, dichlorndifluornmethane and dichlorotetrafluoroethane.

9. A composition as claimed in claim 7, wherein the hydrocarbons are selected from butane, propane and isobutane.

10. A composition as claimed in claim 7, wherein the propellant is a blend of 10 to 50% by weight trichlorofluoromethane and 50 to 90% by weight dichlorodifluoromethane.

11. A composition as claimed in claim 7, wherein the propellant is a blend of 40 to 80% by weight of dichlorodifluoromethane and 20 to 60% by weight of dichlorotetrafluoroethane.

12. A composition as claimed in claim 7, wherein the propellant is a blend of 20 to 50% by weight dichlorodifluoromethane and 50 to 80% by weight butane.

13. A composition as claimed in claim 7, wherein the propellant is a blend of 20 to 40% by weight dichlorodifluoromethane and 60 to 80% by weight dimethyl ether.

14. A method of making an aerosol composition comprising, under conditions that reduce or remove humidity, adding finely divided povidone-iodine and lactose powders to a liquid propellant, mixing by mechanical agitation so as to disperse the powders uniformly within the liquid propellant dosing the resultant slurry into sterile aerosol containers, inserting a sterilised aerosol valve to seal the container and injecting further propellant to make up the amount as desired.

15. A method as claimed in claim 14, wherein said adding and mixing are carried out under nitrogen.

16. An aerosol composition substantially as herein described with reference to the Example.