Correspondence ! I I I

Topical capsaicin for treatment of neuralgia associated with herpes zoster infection

To the Editor: I read with interest the article by Bern- stein et al (J AM ACAD DERMATOL 1987;17:93-6) en- titled "Treatment of Chronic Postherpetic Neuralgia With Topical Capsaicin." The authors treated patients with severe intractable postherpetic neuralgia of greater than 6 months ' duration. Three-fourths of the patients complet ing the study experienced substantial relief of pain.

1 report a case of a patient with herpetic neuralgia treated successfully with topical capsaicin 2 to 3 weeks after the onset of the viral eruption. To my knowledge there has been no other report of treatment of herpetic neuralgia with capsaicin at such an early stage.

Case report. A 51-year-old black woman came to us with a complaint of severe pain localized to the left trunk of 2 to 3 weeks' duration. The pain had been accompanied by a vesicular eruption forming crusts that had fallen off. The patient had applied topical over-the-counter salves and steroid creams and ingested numerous analgesics without alleviation of the burning and throbbing sensation. She sought medical attention because the pain had increased in intensity and she was unable to sleep.

Physical examination revealed areas of postinflammatory hyperpigmentation, a few crusted lesions, and faint erythema in a T10 distribution along the /eft flank. The patient was otherwise healthy except for the recent onset of hypertension, which was controlled with antihypertensive medications (rnethyldopa and hydrochlorothiazide). The clinical diagnosis of resolving herpes zoster with associated herpetic neuralgia was made.

The patient was instructed to apply 0.025% capsaicin cream (Zostrix; GenDerm Corporation, Northbrook, IL) lo- cally to the painful area of the skin 3 to 4 times daily. She was informed that it might take up to 2 weeks before relief (if any) would occur. Two days later a grateful, well-rested patient returned to report that she was pain-free and had ex- perienced a significant decrease in pain even after 1 day of application of the cream. The patient continued using the medication for another 2 days and then stopped on her own accord because she felt cured. There was no complaint of adverse reactions to the medication.

At follow-up evaluation 6 weeks later there had been no recurrence of pain. The patient did, however, occasionally perceive a sensation of warmth in the previously affected dermatome when she was angry or emotionally upset. There was no discomfort and the sensation subsided spontaneously within minutes. In addition, during treatment with capsaicin the affected area felt numb. This continued for 7 to 10 days after the last application of capsaicin, when normal sensation had returned.

Comment. The use of topical capsaicin to alleviate the pain and discomfort of intractable postherpetic neu- ralgia is a significant stride in treating a condition that is frustrating both for the patient and for the physician. The pain is usually recalcitrant to the essentially symp- tomatic management by potent analgesics and tran- quilizers. ~ It can lead to despair and even suicide.

Substance P is an endogenous neuropeptide thought to be important in the transmission of pain from the periphery to the central nervous system, z Capsaicin (trans-8-methyl- N-vanillyl-6-nonenamide) is believed to deplete and prevent the reuptake of substance P in peripheral sensory neurons?

In Bernstein et al 's report of topical capsaicin for chronic postherpetic neuralgia (7 months to 2 years duration) a total positive response rate of 67% in 2 weeks and 75% in 4 weeks was observed. Therefore the quick and dramatic response of my patient's neu- ralgia to topical capsaicin was a pleasant surprise. This case report is not a controlled study and the power of the placebo effect cannot be ruled out. Nevertheless, the dramatic decrease in pain experienced by the patient warrants further investigation into the role of topical capsaicin in the early treatment of herpetic neuralgia. Capsaicin could possibly be used to manage the asso- ciated pain of herpes zoster and prophylactically to de- crease the incidence o f chronic postherpetic neuralgia.

Philip C. Don, M.D., Ph.D. 3611 Bainbridge Rd., Cleveland Heights, OH 44118

REFERENCES 1. Kepes ER. Management of pain. In: Cape RDT, Coe RM,

Rossman I, eds. Fundamentals of geriatric medicine. New York: Raven, 1983:247-58.

2. Hokfelt T, Kellerth JO, Nilsson G, Pernow B. Sub- stance P: localization in the central nervous system and in some primary sensory neurons. Science 1975;190: 889-90.

3. Jessell TM, Iversen LL, Cuello AC. Capsaicin-induced depletion of substance P from primary sensory neurons. Brain Res 1978;152:183-8.

Reply

To the Editor: Dr. Don's report of a patient with acute herpetic neuralgia treated with topical capsaicin cream is certainly of great interest and, as he suggests, should stimulate initiation o f a double-blind controlled study of this agent in postzoster pain of lesser duration than

1135

1136 Correspondence

Journal of the American Academy of

Dermatology

the patients we reported. However, several comments on Dr. Don's case report are in order:

1. We have not had experience with capsaicin in acute zoster pain. However, while we have observed patients with chronic postherpetic neuralgia who have reported relief of pain after 2 or 3 days of capsaicin treatment, these are a distinct minority. Chronic neu- ralgia patients treated in our open-blind study, as well as the vast majority of those we have treated in a large ongoing double-blind clinical trial, have not noted sig- nificant relief of pain until after 2 to 4 weeks of treat- ment. Therefore, we would not want the patient with chronic pain or the treating physician to have overly optimistic expectations of the onset of clinical response. Such unrealistic expectations could interfere with pa- tients receiving a sufficient course of therapy.

2. The patient reported by Dr. Don had no further pain after discontinuing topical capsaicin following 4 days of regular usage. In our experience, which in- volves long-term follow-up of over 30 patients with chronic postherpetic neuralgia for periods of up to 18 months after they first were treated with capsaicin, such a dramatic response was not observed. A number of patients who had good pain relief on capsaicin treatment for lengths varying from 2 to 6 months had a recurrence of pain once capsaicin was discontinued and they had to be restarted on capsaicin.

3. It is, of course, possible (and maybe even prob- able) that the differences in the time course of the re- sponses we have observed to capsaicin versus that de- scribed by Dr. Don can be explained by our patients having pain for 6 months or longer and his patient having pain of only 2 to 3 weeks' duration. It is gen- erally thought that acute neuralgic pain involves exclu- sively a peripheral component, while neuralgias of lon- ger duration may involve an additional central com- ponent to the pain. For this reason, capsaicin, which is thought to act principally on a peripheral chemomedia- tor of pain, might be more effective in relieving the pain of acute neuralgia than that of chronic neuralgia. We have generally avoided treating such acute cases with capsaicin because of our concerns about applica- tion of the agent to open lesions, which possibly could cause exacerbation of pain.

Dr. Don's observation is thought-provoking. If his results can be replicated in a much larger sample under a double-blind paradigm, capsaicin cream might offer safe and effective prophylaxis against postherpetic neu- ralgia, rather than simply a safe and effective treatment for this chronically painful disorder.

Joel E. Bernstein, M.D. 425 Huehl Road, #10, Northbrook, IL 60062

Aene necroticans (varioliformis) and Staphylococcus aureus

To the Editor: Kossard et ai performed a great service to dermatologists by once again focusing attention on acne necroticans (varioliformis), a not uncommon and long-recognized dermatologic condition much ne- glected in the literature.'

One is surprised that the authors of the article, "Nee- rotizing Lymphocytic Folliculitis: The Early Lesion of Ache Necrotica (Varioliforrnis), ''2 did not culture the lesions. The association if not the etiology of this con- dition with S. aureus has been well documented) In addition, they did not cite Maibach's fastidious docu- mentation of scalp folliculitis induced by Corynebac- terfl~rn (Propionibacterium) aches. 4

I have collected a series of thirteen patients with this condition. Eight are female and five male. One was in her teens, one in her twenties, two in their thirties, and the rest over 40. Bacterial cultures revealed oxacillin- sensitive S. aureus in eleven, trimethoprim sulfa- sensitive Klebsiella pneumoniae in one, and Acineto- bacter calcoaceticum in the other. Questioning or observation by next of kin revealed one common factor in all, "the patient picks or manipulates the lesions." Several complained of itching of the lesions, an obser- vation noted by others and one that induces scratching?

A recent spate of correspondence in The Schoch Let- ter documents clinicians' therapeutic frustrations with this venerable condition.* My hypothesis is that the initial lesion of acne necroticans is a folliculitis, prob- ably a rosaeea variant, as speculated by Kossard et at,2 with Propionibacterium acnes as the microbiologic agent. The patient manipulates and excoriates the initial folliculitis, papules, and pustules, which progress to the crusting, necrotic eschars and ultimately scarring le- sions constituting this condition, a situation emphasized by Calnan and O'Neill. 6 Treating the folliculitis with appropriate antibiotics is inadequate. The therapist must contend with the auto-induced component that may be construed as neurotic or anxiety-induced. Patients admit to being "highstrung" or intensely anxious. 5 In two el- derly patients the onset came after diminished mentation following cerebrovascular incidents. In several in- stances, situational factors were cited, that is, loss of job or spouse and marital or family discordance.

I prescribed doxepin for the psychologic aspects, for this tricyclic's combined antidepressive 7 and, in addi-

*Moran RJ et al. The Schoch Letter 1986;35"45 (December). Potter B. The Schoeh Letter 1986;36:4 (January). Upton GL. The Schoch Letter 1986;36:5 (February). Fisher KJ. The Schoeh Letter 1986;36:12 (March).