SCABIES AND PEDICULOSIS TREATED WITH BENZYL BENZOATE, DDT, BENZOCAINE EMULSION

SCABIES AND PEDICULOSIS TREATED WITH BENZYL BENZOATE, DDT, BENZOCAINE EMULSION INCLUDING A C0MPAIUSON WITH OTHER METHODS USED AT U. S. NAVAL HOSPITAL, BROOKLYN, N. Y., FROM NOVEMBER 1943 TO MAY 1945 CEDRIC C. CARPENTER, M.D., JOHN A. HEINLEIN, M.D., MARION B. SULZBERGER, M.D., RUDOLF L. BAER, M.D. War, with its close quartering of men and its overcrowded conditions which favor contagion, always produces a sharp increase in the incidence of scabies. The importance of scabies in loss of manpower is evident from the fact that even in the prewar period it was the second most prevalent skin disease in the Navy, accounting for 14% to 19% of all dermatological admissions. During this peace-time period scabies in the Navy caused 8 days of illness for each person afflicted, which was only one less sick day than during World War I (1, 2, 3). REVIEW OF' OLDER METHODS Because of its military and war-time importance the prevention and treatment of scabies has again received much attention during the present conflict. The older methods of therapy have been reviewed, and new remedies investigated, in an attempt to find a more rapid and more acceptable method of treatment. Much of the recent and authoritative work on scabies has been carried on in Great Britain, where inadequate housing facilities and vercrowded air-raid shelters encouraged the rapid dissemination of the disease. Among the newer insecticides which have been investigated as therapeutic measures are: Derris Root (4), Rotenone (5), Tetraethylthiuram Monosulfide as a 25% emulsion or lotion (6, 7), or incorporated in a soap (8), Mitigal (dimethylthianthrene) (9), Pyrethrum (10), etc. These agents, with the exception of Mitigal, required repeated applications over a period of several days and were on the whole either more irritating or not as reliable as the accepted sulfur ointment routine (11). Shorter or more pleasant methods of applying sulfur, such as the one day Danish or Hospital St. Louis or Hardy method (12), sulfur foam applicators (13), and those employing various new vanishing cream bases have been described. These methods, too, have often proved to be either more irritating or less dependable than the classic 3 day sulfur ointment procedure (11). It is not surprising that some of the short sulfur treatments fail, since it has been demonstrated that the acarus may survive for many hours or even days when placed in sulfur ointment (14). The opinions or assertions contained herein are the private ones of the authors and are not to be construed as official or reflecting the views of the Navy Department or the Naval Service at large. Received for publication January 5, 1946. 93

94 THE JOURNAL OF INVESTIGATIVE DERMATOLOGY ANALYSIS OF ANTISCABIETIC TREATMENTS AT A NAVAL HOSPITAL 1. Sulfur Treatment It has been the practice in the Navy to treat scabies in the hospital. From November 1943 until March 1944 the majority of our hospitalized scabies cases were treated with 15% sulfur ointment, applied twice daily for three successive days (11). This produced a rather high incidence of secondary dermatitis, which necessitated a few days of soothing therapy before the patient could be returned to duty. The average period of hospitalization was 10 days, and occasional recurrences were encountered. This treatment, it might be added, was not popular with the patients, who not only resented their slimy existence, but were forced to remain in pajamas. 2. Benzyl Benzoate In 1937 A. Kissmeyer (14) reported over-all good results in 8,000 cases of scabies each treated with a single application of an emulsion of bensyl benzoate. This chemical is a volatile oil obtained from the well known antiscabietics balsam of Peru and balsam of Tolu. Recently there have been many favorable clinical reports on benzyl benzoate and it has been shown that a 25% emulsion of this agent is capable of destroying the itch mite in five minutes on a glass slide (15). From March to October 1944 we used a lotion of benzyl benzoate 33% in equal parts of soft soap and isopropyl alcohol for the majority of our scabietic patients, employing the method outlined in the Manual of Military Dermatology (11). This consisted of two applications daily for two successive days, followed by a hot soapy shower. This treatment was an improvement over the former measures. In the majority of cases, hospitalization could be reduced from 10 to an average of 5 days. But in some of the patients an additional two or three days of soothing therapy was required because of residual dermatitis. Our experience with benzyl benzoate emulsions coincides with that of others and indicates that dermatitis is less frequently produced if only one or two applications of the emulsion are used instead of 4 (16, 17). Of course irritations are further reduced if the concentration of benzyl benzoate is lowered and if the patients can be so selected as to exclude those with secondary dermatitis due to long continued scratching or from previous over-vigorous antiscabietic therapy (17, 18, 19). On the whole, therapy with the benzyl benzoate emulsion has been well tolerated and accepted by the patients. Despite the sensation of burning and smarting of the skin which occurs with each application, and despite a superficial exfoliation of the scrotum resulting from repeated treatments, this form of therapy is resented less by the patient than the sulfur ointment methods. Scabietic recurrences were extremely rare but tended to increase with the reduction of concentration of benzyl beuzoate and with the reduction in number of applications in our cases. Attempts at further improvements in particular increase of effectiveness of a

SCABIES AND PEDICULOSIS 95 single application coupled with a reduction of dermatitis and stinging led to study of new modifications and combinations containing benzyl benzoate. 3. N.B.1.N. (Benzyl Benzoate, D.D.T. and Benzocaine Emulsion) Beginning in October 1944, we were asked to evaluate the antiscabietic efficacy of the following emulsion which had been developed by Mr. G. W. Eddy and submitted to us for trini by Mr. E. F. Knipling of the Bureau of Entomology, U. S. Department of Agriculture (20). Benzyl Benzoate 10% D.D.T 1% Benzocaine 2% "Tween 80" 2% Water to make 100% For practical reasons this emulsion can be first prepared and stored as a concentrate of the following formula, which is diluted with 5 parts of water before use: Benzyl Benzoate 68% D.D.T 6% Benzocaine 12% "Tween 80" 14% This formula, known as N.B.I.N., combined the miticidal effect of benzyl benzoate, the larvicidal and lousicidal action of D.D.T. (Dichiorodiphenyltrichlorethane) and the ovicidal and antipruritic action of benzocaine. It has not yet been established just how much of the antiscabietic efficacy of this combination is attributable to each of the individual ingredients. it is of course certain that the benzyl benzoate is very effective as a miticide. On the other hand the antiscabietic value of D.D.T. itself is still a moot point. Thus, for example, Elmes (21) reports excellent results with 5% D.D.T. in acetone in the treatment of sarcoptic and psoroptic mange of rabbits; while Mellanby in a discussion of Buxton's report (22) states that D.D.T. is surprisingly inefficient against human scabies. Emulsification and mixing of the ingredients were accomplished by the use of "Tween 80" (Atlas Powder Co.). By combining the three active ingredients the concentration of each could be left relatively low in the endeavor to reduce the incidence of irritations or sensitization from the individual constituents. Moreover it was hoped that the emulsion mixture would penetrate the burrows and be active against all stages in the development of the scabies mite, thus permitting expectation of cures from one application (23). Further possible advantages consisted in having a single preparation which should prove effective against other larvae and mites and also against pediculi and perhaps other biting insects.

96 THE JOURNAL OF INVESTIGATEVE DERMATOLOGY From October 1944 to May 1945, 42 cases of scabies were treated with the N.B.I.N. emulsion: N.B.I.N. is sufficiently low in viscosity to be sprayed on the skin with an ordinary type nasal spray. 50 to 60 c.c. was enough to spray the patient from neck to feet. A piece of gauze was then used to gently rub the liquid into the skin. No preparatory bath was necessary, and the patient was instructed not to bathe for 24 hours following treatment. RESULTS In all patients the pruritus disappeared within twelve hours and sometimes within a few minutes. A mild dermatitis sufficient to require further soothing therapy developed in only one of the uncomplicated cases. Four patients had a complicating infectious dermatitis before the start of treatment. This eruption was aggravated, as previously has been found to be the case when any other antiscabietic formulas were employed. Two patients developed erythematous macular lesions surrounding the sites of the original scabietic papules, suggestive of an allergic reaction to the liberated products of the scabies mite (24), or possibly a reaction set up by the emulsion itself where it entered the burrows. There was only one recurrence and this was in a patient who had no rubbing in of the emulsion following the spray. Because of the 1% D.D.T. contained in the emulsion, all patients were carefully studied for possible toxic effects. There were no toxic symptoms, no insomnia, hyper-excitability, tremors, or evidence of liver damage, nor any appreciable differences in the blood count and urinalysis taken before and after the treatments, in spite of the fact that two patients received four applications of the prescription within two days, one patient three, and two others two applications each. The result of one application of N.B.I.N. was so satisfactory in the hospitalized patients that finally many cases were treated ambulatorily and entirely as "outpatients." They were asked to bring with them a complete set of clean clothes, and after the single treatment changed to the fresh garments. They were instructed not to bathe for 24 hours and to change into clean night clothes and bed linen before retiring that night. No recurrences were seen in any of these patients during the three weeks' period of follow-up observation. N.B.I.N. TREATMENT OF PEDICULOSIS PUBIS AND PEDICULOSIS CAPITIS We have also used this prescription on.15 cases of pediculosis pubis and 4 of pediculosis capitis. In each instance a single, simple spraying has been sufficient to destroy all pediculi and ova, provided the patient did not bathe for two or three days, or shampoo for at least a week following the application. SUMMARY AND CONCLUSIONS 1. Benzyl beuzoate emulsions, introduced by A. Kissmeyer, constitute an improvement over most older measures of antiscabietic treatment.

SCABIES AND PEDICULOSIS 97 2. A further increase of effectiveness, reduction of stinging and of irritations has been achieved in N.B.I.N. emulsion developed by G. W. Eddy of the U. S. Department of Agriculture (mixture of benzyl benzoate, D.D.T., and benzo.. caine in an emulsion of "Tween 80" and water). 3. One to four sprayings with this clean and easily applied emulsion produced permanent cures in 41 of 42 patients. In most cases a single spraying sufficed. 4. A single application of the N.B.I.N. emulsion was effective also in curing 15 cases of pediculosis pubis and 4 cases of pediculosis capitis. 5. In the present cases there were no evidences of toxicity and no increase of skin irritancy. The preparation was easier and more pleasant to use, and less irritating than older measures used against scabies and pediculosis. 6. Further clinical studies are required to confirm the lack of toxicity of D.D.T. when used on large series of persons in emulsions such as N.B.I.N. BIBLIOGRAPHY 1. SULZBERGEU, MARION B., MACCLATCHIE, L. K. AND PARSONS, R. P.: Military Dermatology and Syphiloiogy. Med. Clinics of North America, 25:6 page 1677 (November) 1941. 2. Navy Department, Bureau of Medicine and Surgery, Statistics of Diseases and Injuries in the U. S. Navy for Calendar Year 1941. Pages 67 and 106. 3. FRIEDMAN, REUBEN: Scabies Civil and Military (Its prevalence, prevention, and treatment). Froban Press, N. Y. 1941. Pages 114 and 147. 4. SAIJNDERS, L.: Derris Root Treatment of Scabies. Brit. M. J., 1: 624 (April 26) 1941. 5. EPSTEIN, E.: Treatment of Scabies with Rotenone. Arch. Dermat. and Syph., 45: 950 (May) 1942. 6. BEADSHAW, D. B.: Tetra Ethylthihram Monosulfide in Treatment of Scabies. Lancet, 2: 273 (April 26) 1944. 7. CLAYTON, T. M.: Treatment of Scabies by Tetra Ethylthiuram Monosulfide. Brit. M. J., 1: 443 (April 10) 1943. 8. GORDON, R. M., et al.: Control of Scabies by Use of Soap Impregnated with Tetra- Ethylthiuram Monosulfide. Brit. M. J., 1:803 (June 17) 1944. 9. MATTHEWS, A. D.: Treatment of Scabies. Brit. M. J., 1: 16 (January 6) 1944. 10. SWEITZER, S. E. AND TEDDER, J. W.: Pyrethrum in the Treatment of Scabies. Minnesota Medicine, 18: 793 (December) 1935. 11. PILLSBURY, D. M., SULZBERGEE, MARION B., AND LIVINGOOD, C. S.: Manual of Dermatology, W. B. Saunders Co., Phila. 1943. Pages 31 and 32. 12. OPPENHEIM, M. AND SMITH, H. A.: Treatment of Scabies in Wartime. Arch. Dermat. and Syph., 48: 370 (October) 1943. 13. NoLAN, R. A.: Sulphur Soap Paste in Treatment of Scabies. Arch. Dermat. and Syph., 36: 846 (October) 1937. 14. KISSMEYER, A.: Rapid Ambulatory Treatment of Scabies with Benzyl Benzoate Lotion. Lancet, 1: 21 (January 2)1937. 15. ROXBURGH, A. C.: Scabies. Practitioner, 149: 228 (October) 1942. 16. SLEPYAN, A. H.: A Rapid Treatment of Scabies. J. A. M. A., 124: 1127 (April 15) 1944. 17. GRAHAM, J. R.: Scabies Treated with One Application of Benzyl Benzoate. Brit. M. J., 1:413 (April 3)1943. 18. GOLDMAN, L.: Complication of Scabies. War Med., 5: 294 (May) 1944. 19. MACCORMAC, H.: Three Skin Diseases in Wartime. Brit. M. J., 2: 667 (November 27) 1943. 20. EDDY, G. W.: A Combination Treatment for Lice and Scabies. In press. 21. ELMES, B. G. T.: DDT Treatment of Mange (Scabies) in Rabbits. Lancet, 248: 563, 1945.

98 THE JOURNAL OF INVESTIGATIYR DERMATOLOGY 22. MELLANBY, K. in discussion to BUXTON, P. A.: The Use of the New Insecticide DDT in Relation to the Problems of Tropical Medicine. Transactions of the Royal Society of Tropical Medicine and Hygiene. Vol. XXXVIII No. 5, May 1945. 23. KNIPLING, E. F.: Senior Entomologist, Bureau of Entomology and Plant Quarantine, U. S. Department of Agriculture. Personal Communication to Comdr. M. B. Sulsberger (MC) USNR. (September) 9144. 24. SULZBRROER, MARION B. AND Btsu, R. L.: Editor's Comment on Goldman, L. Complications of Scabies. Year Book of Dermat. and Syph., 1944, page 315.