Unacceptable side-effects of oral zinc sulphate in the treatment of acne vulgaris

Zinc therapy in dermatology: a review

Zinc, both in elemental or in its salt forms, has been used as a therapeutic modality for centuries. Topical preparations like zinc oxide, calamine, or zinc pyrithione have been in use as photoprotecting, soothing agents or as active ingredient of antidandruff shampoos. Its use has expanded manifold over the years for a number of dermatological conditions including infections (leishmaniasis, warts), inflammatory dermatoses (acne vulgaris, rosacea), pigmentary disorders (melasma), and neoplasias (basal cell carcinoma). Although the role of oral zinc is well-established in human zinc deficiency syndromes including acrodermatitis enteropathica, it is only in recent years that importance of zinc as a micronutrient essential for infant growth and development has been recognized. The paper reviews various dermatological uses of zinc.

Zinc, its biological role and use in dermatology

This literature review detines the biological role ot zinc in the human body, immune homeostasis and skin physiology as well as pathophysiology ot skin diseases. It describes the current range ot systemic and topical zinc preparations and their pharmacological characteristics. The review also describes skin diseases that may be treated with the use ot zinc preparations on a grounded basis, and discloses the clinical experience ot the use ot these drugs described in the world literature. It sets out certain recommendations tor using zinc preparations in clinical practice.

Innovative uses for zinc in dermatology

Severe zinc deficiency states, such as acrodermatitis enteropathica, are associated with a variety of skin manifestations, such as perioral, acral, and perineal dermatitis. These syndromes can be reversed with systemic zinc repletion. In addition to skin pathologies that are clearly zinc-dependent, many dermatologic conditions (eg, dandruff, acne, and diaper rash) have been associated and treated with zinc. Success rates for treatment with zinc vary greatly depending on the disease, mode of administration, and precise zinc preparation used. With the exception of systemic zinc deficiency states, there is little evidence that convincingly demonstrates the efficacy of zinc as a reliable first-line treatment for most dermatologic conditions. However, zinc may be considered as an adjunctive treatment modality. Further research is needed to establish the indications for zinc treatment in dermatology, optimal mode of zinc delivery, and best type of zinc compound to be used.

Diet and acne

Historically, the relationship between diet and acne has been highly controversial. Before the 1960s, certain foods were thought to exacerbate acne. However, subsequent studies dispelled these alleged associations as myth for almost half a century. Several studies during the last decade have prompted dermatologists to revisit the potential link between diet and acne. This article critically reviews the literature and discusses how dermatologists might address diet when counseling patients with acne. Dermatologists can no longer dismiss the association between diet and acne. Compelling evidence exists that high glycemic load diets may exacerbate acne. Dairy ingestion appears to be weakly associated with acne, and the roles of omega-3 fatty acids, antioxidants, zinc, vitamin A, and dietary fiber remain to be elucidated. This study was limited by the lack of randomized controlled trials in the literature. We hope that this review will encourage others to explore the effects of diet on acne.

Effective over-the-counter acne treatments

Acne is the most common disease of the skin, yet only a fraction of acne sufferers are treated with prescription products by physicians. There is, however, a large and expanding market for over-the-counter (OTC) medications, many of which are not only effective but also well tolerated and cosmetically elegant. Given the presence of OTC acne medications on the television, the Internet, and store shelves, patients will be acutely aware of these OTC remedies and will have questions. Patients will expect dermatologists to advise them regarding products to use either as a sole therapy or in combination with prescription drugs. Recently, combinations of OTC acne medications in treatment regimens or "kits" have gained popularity and appear to have increased patient compliance. Quality-of-life outcomes from OTC medication use, in at least one study, have demonstrated good benefit. The most common OTC ingredients include benzoyl peroxide, a potent antibacterial agent, and salicylic acid, a mild comedolytic and antiinflammatory medication. Other, less-common OTC ingredients include sulfur, sodium sulfacetamide, and alpha hydroxy acids. Zinc, vitamin A, tea tree oil, and ayurvedic therapies also are available OTC for acne. Additional and better studies are needed to clarify the benefit of these latter medications.

Zinc in skin pathology and care

OBJECTIVES

To assess the significance of zinc in the etiology of various dermatological conditions and examine the role of zinc as a mode of treatment for a wide range of dermatoses.

METHODS

Review of existing literature through searches using the PubMed site with zinc and the dermatosis in question as search words.

RESULTS

Severe zinc deficiency states such as acrodermatitis enteropathica are associated with a variety of skin manifestations, such as perioral, acral and perineal dermatitis. These syndromes can be reversed with systemic zinc repletion. In addition to skin pathologies which are clearly zinc-dependent, many dermatological conditions (e.g. dandruff, acne and diaper rash) have been associated and treated with zinc. Success rates for treatment with zinc vary depending on the disease, mode of application and zinc salt used. Usually, alternative modes of treatment are superior to zinc.

CONCLUSIONS

Generally, it seems that with the exception of systemic deficiency states, there is very little evidence to convincingly demonstrate the efficacy of zinc as a first-line treatment for any dermatological conditions. Further research is needed in order to establish the indications for zinc treatment in dermatology, optimal mode of delivery, type of compound and therapeutic indexes.

Oral zinc sulfate in the treatment of Behcet's disease: A double blind cross-over study

This was a randomized, controlled, double-blind trial of zinc sulfate in the treatment of Behcet's disease. Patients with Behcet's disease were recruited in this study between November 2001 and February 2003. A clinical manifestations index (CMI) was calculated for each patient. Serum zinc was estimated in all patients both at the beginning and monthly throughout the trial. Serum zinc levels were estimated from 30 healthy normal subjects matched for age and sex as a control group. Patients were randomly allocated to receive either 100 mg zinc sulfate or identical placebo tablet three times daily in a double-blind manner. After 3 months of starting treatment, patients were crossed over, that is, patients on placebo received zinc sulfate and vice versa. Mean serum zinc level in Behcet's disease patients was statistically significantly lower than mean serum zinc levels in healthy the control. In group A (started with zinc sulfate), the mean CMI started to decline directly after the first month of therapy with zinc sulfate to significantly lower levels. After shifting to placebo treatment in the fourth month, the mean of CMI started to rise again gradually but remained significantly lower than levels before therapy for the fourth and fifth months. In group B (started with placebo), the mean of CMI remained high for the first 3 months. After crossing over to zinc sulfate in the fourth month, the mean of CMI started to decrease after the fourth month. An inverse correlation between CMI and serum zinc level was found. No side-effects were seen in either group. In conclusion, zinc sulfate was found to be a good option in the treatment of Behcet's disease.

A double-blind trial of a zinc sulphate/citrate complex and tetracycline in the treatment of acne vulgaris

Forty-eight patients participated in a 3-month double-blind study to compare the effect of orally administered zinc sulphate/citrate complex and tetracycline hydrochloride in acne vulgaris. Tetracycline significantly reduced the overall grade, and the number of non-inflamed lesions, papules and pustules by the third month. It also reduced significantly the non-inflamed lesions and papules at the end of the second month. In contrast, zinc therapy only had a significant effect on the pustules at the third month. The results indicate that tetracycline is far superior to the zinc complex in patients with moderately severe acne.