WO2004052358A1

WO2004052358A1 - Urushiol induced contact dermatitis treatment and method of use

Info

Publication number: WO2004052358A1
Application number: PCT/US2002/038609
Authority: WO
Inventors: William Yarbrough
Original assignee: The William Yarbrough Foundation
Priority date: 2002-12-04
Filing date: 2002-12-04
Publication date: 2004-06-24
Also published as: AU2002351219A1

Abstract

A treatment for urushiol induced contact dermatitis is provided for in a topical treatment. According to the invention, the composition comprises at least one ethoxylate in combination with a supporting agent. It is believed that this combination binds to the available urushiol receptors rendering it inactive. The affinity of the receptors for the ethoxylates also appears to cause a release of the urushiol from its epidermal bonds for bonding to the composition. An inert scrubbing agent, such as polyethylene beads, can also be included to assist in the release of the urushiol. Acetylated lanolin alcohol, EDTA, a foam stabilizer, and water can also be added to the composition without effecting performance. A method of use is also provided for applying the composition of substances to the affected area, working the composition into the affected area, and removing the composition from the affected area.

Description

INVENTION TITLE: Urushiol Induced Contact Dermatitis Treatment and

Method of Use

I. TECHNICALFIELD

The present invention relates to soaps for the treatment of allergic dermatitis and more particularly to a soap for use in cases of dermatitis resulting from contact with the Rhus oleoresin, urushiol.

II. BACKGROUND ART

Urushiol or related chemicals is found in many species of plant. It is the toxin responsible for the allergic dermatitis caused by contact with the sap of commonly encountered noxious plants such as, for example, the lacquer tree of Asia (Indian and Japanese), mango tree, Brazilian Pepper tree, poison wood, poison ivy, poison oak, and poison sumac, and in certain nutshells such as the walnut and cashew. Many other related plants found throughout the world also contain urushiol, most but not all of which are found in the Anacardiaceae group.

In the United States, the American Academy of Dermatology estimates that there are up to 50 million cases of urushiol induced contact dermatitis annually in the United States alone. No one is sure of the number of world wide annual exposures but some experts estimate that the number could be double that of the United States. Many industrial workers, e.g., agriculture and paint (lacquer), suffer from urushiol induced contact dermatitis. Accordingly, urushiol induced contact dermatitis is a world wide problem. Chemically, urushiols are mixtures of catechols with long, hydrophobic, carbon(alkyl) side chains at the three position of the catechol ring. For example, poison ivy contains predominantly 3-rø-pentadececylcatechols (C-15) and poison oak contains predominantly 3-n- heptaecylcatechols (C-17). When located inside an unruptured plant leaf, urushiol is a light, colorless oil. When exposed to oxygen, urushiol easily oxidizes and, after polymerizing, turns a blackish color.

Current theory suggests that the reaction to urushiol is a delayed cell- mediated immune response in which, upon first exposure, urushiol penetrates the stratified squamous epithelial cells and binds to the Langerhan cells, which, in turn, sensitize effector T-cells in the lymph system. Subsequent exposures to urushiol result in the release of cytokines and reaction by macrophages and cytotoxic T-Cells. The result of lytic enzyme and perforin release is destruction of the membrane-bound urushiol and surrounding skin cells, which presents as the commonly seen clinical

picture.

Once urushiol touches the skin, it begins to penetrate in minutes. It is completely bound to the skin after eight hours (two to six hours according to some experts). The rash generally develops within two days. Redness and swelling occur, often followed by blisters and severe itching. In a few days, the blisters may become crusted and begin to scale. The rash generally peaks after five days, and starts to decline after about a week or 10 days. The rash takes two or more weeks to heal. In a severe case or in a systemic reaction, individuals will many times present with black spots in areas of heavy urushiol concentration. The black spots are polymerized urushiol in a pure form and need to be removed immediately. This "Black Spot" test (attributed to Guin) is good indicator of a severe reaction, localized or systemic, or is often seen in cases of poison oak (typically a more tenacious reaction than poison ivy).

The rash can affect almost any part of the body, especially where the skin is thin, such as on the face. A rash develops rarely on the soles of feet and palms of hands, where the skin is thicker. The rash does not spread, although it may seem to do so when it breaks out in new areas. This may happen because urushiol absorbs more slowly into skin that is thicker, such as on forearms, legs and the body's trunk. Urushiol can be transferred by fingernails or animal fur and can remain on clothing, shoes, and tools for up to five years in moist climates and nine years in dry climates. Scratching the rash does not spread the urushiol to other parts of the body, but it can prolong the discomfort and cause a secondary infection.

Treatment has historically consisted of attempting to remove the oil as quickly after exposure as possible: applying rubbing alcohol, washing effected areas with water, and showering with soap and water. Unfortunately, if the above procedure is not commenced within minutes of exposure the regimen will not remove the toxin but may limit its spread.

Attempts have been made to find both prophylactic treatments as well as post- exposure treatments. To date, no vaccine has been developed and the prior art treatments are not without shortcomings. One treatment example is seen in U.S. Patent number 5,686,074 to Stewart which teaches and claims a treatment for poison ivy which includes a composition including linseed oil, an astringent, a starch, an essential oil and a citrus oil. One shortcoming of this patent is that linseed oil can cause irritation itself. A second shortcoming of this patent is that it requires that the composition be applied to the effected areas up to twice a day until the rash is gone. The composition provides what appears to be only very temporary palliative relief of poison ivy symptoms and does not appear to alter the course of the malady.

Other proposed treatments are seen in U. S. Patent numbers 5,620,527, 5,011,6894,499,086, 4,259,318, 4,002,737, 3,862,331, 3,875,301, and 3,922,342.

Yet other prior art attempts have focused on prophylactics for preventing the dermatitis. One example is seen is U.S. Patent number 4,663,151 to Waali that discloses and claims a prophylactic treatment based upon Aluminum Chlorhydrate. Of course, the most significant shortcoming associated with prophylactic treatments is that they are only effective if applied before exposure to the urushiol; an occurrence that rarely takes place.

Another treatment for poison ivy and poison oak is seen in an unpatented product sold under the mark Tech-Nu ® and manufactured by Tec Laboratories, Inc. of Albany, Oregon. This product was originally developed as a treatment for radiation exposure. It was discovered, however, that the product also provided some relief for poison ivy and oak exposure. The main active ingredient in the Tech-Nu® product is Octylphenoxy-polyethoxyethanol. The four octyl groups of this chemical are too large too surround the non polar moieties in the urushiol. Therefore, it only partially matches the polarity of urushiol. Thus, the action of this product renders the urushiol only partially inactive. Since the urushiol remains partially active and continues to cause irritation, only temporary relief is provided and multiple applications are necessary. Also, the chemical makeup of the product requires that it be applied no later than eight hours after exposure to urushiol.

There is need, therefore, for a safe, effective treatment for dermatitis caused by exposure to the toxin urushiol. The treatment should provide complete relief from the signs and symptoms associated with the dermatitis in limited treatments and should be effective at any point during the dermatitis cycle.

III. DISCLOSURE OF INVENTION

It is an object of the present invention to provide a treatment for urushiol induced allergic dermatitis, the treatment providing almost immediate and permanent relief in usually one treatment.

It is a further object of the present invention to provide such a treatment in a method that utilizes a composition that chemically attaches to available urushiol receptors to block its allergic reaction properties and to release the urushiol so that it can be removed from the skin.

It is a yet further object of the present invention to provide a treatment that is safe to use.

It is yet another object of the present invention to provide a treatment for urushiol induced allergic dermatitis that is topical, can be purchased over the counter and is economical.

As noted above, urushiol is the toxin responsible for the contact dermatitis caused by urushiol containing plants. Urushiol is the name given to a family catechols having long, hydrophobic, carbon (alkyl) side chains at the three position of the catechol ring. For example, the poison ivy plant contains predominantly 3-n- pentadececylcatechols (C-15) and Poison oak contains predominantly 3-n- heptaecylcatechols (C-17). Other urushiol containing plants contain catechols that have side chains of varying lengths.

Urushiol is found in plant roots, stems, branches, and leaves. When housed inside an unruptured plant leaf, urushiol is a light, colorless oil. The slightest contact or even breeze easily damages the leaves. Therefore, it is rare to find a plant that does not have at least some ruptured leaves. When exposed to oxygen, urushiol easily oxidizes and, after polymerizing, turns a blackish color.

The reaction experienced by most people is the result of exposure to the oleoresin containing the urushiol. The reaction is an allergic eczematous contact dermatitis characterized by redness, swelling, papules, vesicles, bullae, and streaking.

It has been discovered that a product manufactured and sold by the Redman Scientific, Company of Dallas, Texas can alleviate the signs and symptoms of urushiol induced contact dermatitis. The product has been sold for approximately twenty years, and is known to be a safe, gentle hypoallergenic product. The product has been has never heretofore been known to be effective against urushiol toxicity. It has only been promoted as a hand cleaner.

Chemical analysis and research by the inventors has revealed that two of the -component parts of the Redman product are central to its effectiveness as a treatment for urushiol induced contact dermatitis: an ethoxylate and Sodium Lauroyl Sarcosinate. The ethoxylate is a nonylphenol ethoxylate. The ethoxylate has its large octyl groups removed. In this way, the ethoxylate creates a partial micelle with the non-polar molecules of the urushiol. Further, the long chain moiety of the present invention's ethoxylate is only four carbons long. This feature also assists the ethoxylate in bonding to the urushiol more effectively. It is important to note that more than one surfactant can be used at a time. Accordingly, the ethoxylate may be used alone or in conjunction with other surfactants to create the appropriate environment. Also, acetylated lanolin alcohol, EDTA, a foam stabilizer, water and other various agents can also be added to the composition without effecting performance.

Further research has revealed that other substances ("hereinafter termed "supporting agents") also are effective in combination with ethoxylates to bind and neutralize urushiol. For example, d-limonene can be used in combination with an ethoxylate to create an effective urushiol binding or neutralizing agent. The chemical result of the ethoxylate/d-limonene combination has an affinity to urushiol that is close but not the same as SLS; thus, d-limonene can be a suitable, but somewhat less effective, substitute for SLS. Further, d-limonene is known to be a mild skin irritant and may cause undue irritation of already disrupted skin.

Other substances that form with the ethoxylate to form a molecule that can create a micelle with the urushiol can also work as supporting agents. However, the ethoxylate itself is not capable of forming a complete micelle around the urushiol. The inventors have discovered that the addition of sodium lauroyl sarcosinate (SLS) completes the micelle and the urushiol can be cleansed away from the skin. SLS also has a long carbon chain that can surround the non-polar portions of the urushiol. In addition, SLS contains a highly polar end that aids in surrounding the polar ends of urushiol and also in the invention's reactivity with water.

Thus, the combination of the ethoxylate and SLS create a large molecule that contains flexible non-polar groups and soluble polar groups. This permits the inventive composition to quickly and effectively surround the urushiol and then be rinsed away with water, a highly polar substance.

The inventors have also discovered that the addition of an inert scrubbing agent improves the action of the inventive composition. The scrubbing agent assists by causing the urushiol to detach from the skin and place it in position for bonding with the active chemical components of the inventive composition. Any inert agent will suffice but the inventors believe that polyethylene beads work best. Another suitable inert agent includes pumice. The beads should be large enough to be effective but not so large as to cause abrasions. The inventors suggest beads in the range of 5 to 50 microns with an average size being approximately 25 microns or 50 mesh. While scrubbing agents are desirable, they are not critical to the invention's use. To make the inventive composition, an exact ratio of ethoxylate and supporting agent is not critical. The only requirement is that the ethoxylate completely reacts with the supporting agent, creating a polymer. This will vary with the ethoxylate and supporting agent used, but, in the case of SLS, a ratio of ethoxylate-to- SLS of 1.5:2 is preferred. The amount by weight of scrubbing agent can vary according to the grittiness desired. In the case of SLS and polyethylene beads, a formula of ethoxylate : SLS :polyethylene of 40:20:40 is preferred but that formulas of other concentrations are useful. Thus, for production purposes, formulas having a supporting agent ranging from 10 to 20 % by weight, ethoxylate ranging from 20 to 40 % by weight, and scrubbing agent from 20 to 50% by weight are reasonable. But again, the formula is not restricted to these ranges, which ranges are presented for example purposes only.

Also, a cutting agent that does not chemically react with the composition may be added. The cutting agent makes the overall composition flow more easily, thereby enabling more packaging options such as tubes. The cutting agent can be either an aqueous based solution or an oil based solution. The cutting agent must be added only in sufficient amount that it promotes flow but does not effect the action of the composition.

Thus, a representative composition for the inventive solution might be polyethylene granules, sodium lauroyl sarcosinate, nonoxynol-9, C12-15 pareth-9, disodium EDTA, quaternium-15, carbomer 2%, triethanolamine, and water.

I

In use, the composition is lathered (it is low foaming) and then applied to an affected area. The composition is then worked over the area by a scrubbing motion. Depending on the supporting agents used, severity of the reaction, and the sensitivity of the individual, sufficient scrubbing time is typically thirty seconds to three minutes. After sufficient time has elapsed to ensure that the affected area has been adequately exposed to the composition, the composition and bound urushiol are washed away. To have the greatest effect, the composition can be left on the affected area, after the initial scrubbing, for a short time, thirty to sixty seconds, and a second rubbing can then be accomplished. The second rubbing period can be shorter than the initial period and than washed away. Experiments have demonstrated that a majority of people needs only one solution to be relieved of itching; however, severe or systemic cases may require two or more application approximately eight hours apart for two days to be fully effective.

Due to the compositions effectiveness in creating a micelle with the urushiol, it can be used effectively at any time during the rash cycle.

Claims

1. A treatment for urushiol induced contact dermatitis comprising Sodium Lauroyl Sarcosinate and a nonyl phenyl ethoxylate in combination.

2. The treatment for urushiol induced contact dermatitis of Claim 1 further including a second nonyl phenyl ethoxylate.

3. The treatment for urushiol induced contact dermatitis of Claim 1 further including Acetylated lanolin alcohol.

4. The treatment for urushiol induced contact dermatitis of Claim 1 further including polyethylene granules.

5. The treatment for urushiol induced contact dermatitis of Claim 1 further including water.

6. The treatment for urushiol induced contact dermatitis of Claim 1 further including ethylenediaminetetraacetic acid.

7. The treatment for urushiol induced contact dermatitis of Claim 1 further including a foam-stabilizing agent.

8. The treatment for urushiol induced contact dermatitis of Claim 1 further including a cutting agent.

9. The cutting agent of Claim 8 being selected from the group of aqueous based solutions and oil based solutions.

10. A treatment for urushiol induced contact dermatitis comprising a nonyl phenyl ethoxylate, Sodium Lauroryl Sarcosinate, and scrubbing means.

11. The treatment of Claim 10 wherein the scrubbing means is selected from the group consisting of polyethylene beads and pumice.

12. The treatment for urushiol induced contact dermatitis of Claim 10 further including a cutting agent.

13. A treatment for urushiol induced contact dermatitis comprising: a first nonyl phenyl ethoxylate, a second nonyl phenyl ethoxylate, Acetylated lanolin alcohol, Sodium Lauroyl Sarcosinate, EDTA, a foam stabilizer, water, and a scrubbing agent.

14. A treatment for urushiol induced contact dermatitis comprising a nonyl phenyl ethoxylate, Sodium Lauroyl Sarcosinate, and EDTA.

15. A method for treating contact dermatitis comprising the steps of: preparing a composition comprising a nonyl phenyl ethoxylate and Sodium Lauroyl Sarcosinate; applying the composition to an affected area; permitting the composition to remain on the affected area a suffcient amount of time to enable the composition of matter to cause an effect; and, removing the composition from the affected area.

16. The method of Claim 15 wherein preparing the composition further includes adding second nonyl phenyl ethoxylate.

17. The method of Claim 15 wherein preparing the composition further includes adding Acetylated lanolin alcohol.

18. The method of Claim 15 wherein preparing the composition further includes adding scrubbing means.

19. The method of Claim 18 wherein the scrubbing means is selected from the group consisting of polyethylene beads and pumice.

20. The method of Claim 15 wherein preparing the composition further includes adding water.

21. The method of Claim 15 wherein preparing the composition further includes EDTA.

22. The method of Claim 15 wherein preparing the composition further includes a foam stabilizer.

23. The method of Claim 15 further including the step of adding a thinning agent to the composition.

24. A solution for urushiol induced contact dermatitis comprising a supporting agent and at least one ethoxylate in combination.

25. The solution for urushiol induced contact dermatitis of Claim 24 wherein one of the at least one ethoxylate is a nonyl phenyl ethoxylate.

26. The solution for urushiol induced contact dermatitis of Claim 24 wherein the supporting agent is sodium lauroyl sarcosinate.

27. The solution for urushiol induced contact dermatitis of Claim 24 wherein the supporting agent is d-limonene.

28. The solution for urushiol induced contact dermatitis of Claim 24 further including Acetylated lanolin alcohol.

29. The solution for urushiol induced contact dermatitis of Claim 24 further including a scrubbing agent.

30. The solution for urushiol induced contact dermatitis of Claim 29 wherein the scrubbing agent is selected from the group of polyethylene granules and pumice.

31. The solution for urushiol induced contact dermatitis of Claim 24 further including water.

32. The solution for urushiol induced contact dermatitis of Claim 24 further including ethylenediaminetetraacetic acid.

33. The solution for urushiol induced contact dermatitis of Claim 24 further including a foam-stabilizing agent.

34. The solution for urushiol induced contact dermatitis of Claim 24 further including a cutting agent.

35. The cutting agent of Claim 34 being selected from the group of aqueous based solutions and oil based solutions.

36. A solution for urushiol induced contact dermatitis comprising at least one ethoxylate, a supporting agent, and scrubbing means.

37. The solution for urushiol induced contact dermatitis of Claim 36 wherein one of the at least one ethoxylate is a nonyl phenyl ethoxylate.

38. The solution for urushiol induced contact dermatitis of Claim 36 wherein the supporting agent is sodium lauroyl sarcosinate.

39. The solution for urushiol induced contact dermatitis of Claim 36 wherein the supporting agent is d-limonene.

40. The solution for urushiol induced contact dermatitis of Claim 36 wherein the scrubbing means is selected from the group of polyethylene granules and pumice.

41. The solution for urushiol induced contact dermatitis of Claim 36 further including water.

42. The solution for urushiol induced contact dermatitis of Claim 36 further including Acetylated lanolin alcohol.

42. The solution for urushiol induced contact dermatitis of Claim 36 further including ethylenediaminetetraacetic acid.

43. The solution for urushiol induced contact dermatitis of Claim 36 further including a foam-stabilizing agent.

44. The solution for urushiol induced contact dermatitis of Claim 36 further including a cutting agent.

45. The cutting agent of Claim 44 being selected from the group of aqueous based solutions and oil based solutions.

46. A method for treating contact dermatitis comprising the steps of: preparing a composition comprising at least one ethoxylate and a supporting agent; applying the composition to an affected area; scrubbing the composition on the affected area; permitting the composition to remain on the affected area a sufficient amount of time to enable the composition of matter to cause an effect; and, removing the composition from the affected area.

47. The method of Claim 46 including the further step of adding a scrubbing agent to the composition.

48. The method of Claim 46 wherein the scrubbing agent is polyethylene granules.

49. The method of Claim 46 wherein the scrubbing agent is pumice.

50. The method of Claim 46 wherein preparing the composition further includes adding Acetylated lanolin alcohol.

51. The method of Claim 46 wherein preparing the composition further includes adding water.

52. The method of Claim 46 wherein preparing the composition further includes EDTA.

53. The method of Claim 46 wherein preparing the composition further includes a foam stabilizer.

54. The method of Claim 46 further including the step of adding a thinning agent to the composition.