Dapsone: unapproved uses or indications

Seabra PS, Fonseca ADN, de Azevedo Sousa KM, de Oliveira SBB, Carneiro ADS, Coleman MD, Monteiro MC. Alpha-Lipoic Acid and Its Enantiomers Prevent Methemoglobin Formation and DNA Damage Induced by Dapsone Hydroxylamine: Molecular Mechanism and Antioxidant Action

Dapsone (DDS) therapy can frequently lead to hematological side effects, such as methemoglobinemia and DNA damage. In this study, we aim to evaluate the protective effect of racemic alpha lipoic acid (ALA) and its enantiomers on methemoglobin induction. The pre- and post-treatment of erythrocytes with ALA, ALA isomers, or MB (methylene blue), and treatment with DDS-NOH (apsone hydroxylamine) was performed to assess the protective and inhibiting effect on methemoglobin (MetHb) formation. Methemoglobin percentage and DNA damage caused by dapsone and its metabolites were also determined by the comet assay. We also evaluated oxidative parameters such as SOD, GSH, TEAC (Trolox equivalent antioxidant capacity) and MDA (malondialdehyde). In pretreatment, ALA showed the best protector effect in 2.5 µg/mL of DDS-NOH. ALA (1000 µM) was able to inhibit the induced MetHb formation even at the highest concentrations of DDS-NOH. All ALA tested concentrations (100 and 1000 µM) were able to inhibit ROS and CAT activity, and induced increases in GSH production. ALA also showed an effect on DNA damage induced by DDS-NOH (2.5 µg/mL). Both isomers were able to inhibit MetHb formation and the S-ALA was able to elevate GSH levels by stimulating the production of this antioxidant. In post-treatment with the R-ALA, this enantiomer inhibited MetHb formation and increased GSH levels. The pretreatment with R-ALA or S-ALA prevented the increase in SOD and decrease in TEAC, while R-ALA decreased the levels of MDA; and this pretreatment with R-ALA or S-ALA showed the effect of ALA enantiomers on DNA damage. These data show that ALA can be used in future therapies in patients who use dapsone chronically, including leprosy patients.

A comprehensive insight into the anti-inflammatory properties of dapsone

The 4,4'-diaminodiphenyl sulfone (DDS), also known as dapsone, is traditionally used as a potent anti-bacterial agent in clinical management of leprosy. For decades, dapsone has been among the first-line medications used in multidrug treatment of leprosy recommended by the World Health Organization (WHO). Shortly after dapsone's discovery as an antibiotic in 1937, the dual function of dapsone (anti-microbial and anti-inflammatory) was elucidated. Dapsone exerts its anti-bacterial effects by inhibiting dihydrofolic acid synthesis, leading to inhibition of bacterial growth, while its anti-inflammatory properties are triggered by inhibiting reactive oxygen species (ROS) production, reducing the effect of eosinophil peroxidase on mast cells and downregulating neutrophil-mediated inflammatory responses. Among the leading mechanisms associated with its anti-microbial/anti-protozoal effects, dapsone clearly has multiple antioxidant, anti-inflammatory, and anti-apoptotic functions. In this regard, it has been described in treating a wide variety of inflammatory and infectious skin conditions. Previous reports have explored different molecular targets for dapsone and provided insight into the anti-inflammatory mechanism of dapsone. This article reviews several basic, experimental, and clinical approaches on anti-inflammatory effect of dapsone.

Development of Novel Chitosan Microcapsules for Pulmonary Delivery of Dapsone: Characterization, Aerosol Performance, and In Vivo Toxicity Evaluation

Pneumocystis carinii pneumonia (PCP) is a major opportunistic infection that affects patients with human immunodeficiency virus. Although orally administered dapsone leads to high hepatic metabolism, decreasing the therapeutic index and causing severe side effects, this drug is an effective alternative for the treatment of PCP. In this context, microencapsulation for pulmonary administration can offer an alternative to increase the bioavailability of dapsone, reducing its adverse effects. The aim of this work was to develop novel dapsone-loaded chitosan microcapsules intended for deep-lung aerosolized drug delivery. The geometric particle size (D 4,3) was approximately 7 μm, the calculated aerodynamic diameter (d aero) was approximately 4.5 μm, and the mass median aerodynamic diameter from an Andersen cascade impactor was 4.7 μm. The in vitro dissolution profile showed an efficient dapsone encapsulation, demonstrating the sustained release of the drug. The in vitro deposition (measured by the Andersen cascade impactor) showed an adequate distribution and a high fine particles fraction (FPF = 50%). Scanning electron microscopy of the pulmonary tissues demonstrated an adequate deposition of these particles in the deepest part of the lung. An in vivo toxicity experiment showed the low toxicity of the drug-loaded microcapsules, indicating a protective effect of the microencapsulation process when the particles are microencapsulated. In conclusion, the pulmonary administration of the novel dapsone-loaded microcapsules could be a promising alternative for PCP treatment.

Dapsone in dermatology and beyond

Dapsone (4,4′-diaminodiphenylsulfone) is an aniline derivative belonging to the group of synthetic sulfones. In 1937 against the background of sulfonamide era the microbial activity of dapsone has been discovered. Shortly thereafter, the use of dapsone to treat non-pathogen-caused diseases revealed alternate antiinflammatory mechanisms that initially were elucidated by inflammatory animal models. Thus, dapsone clearly has dual functions of both: antimicrobial/antiprotozoal effects and anti-inflammatory features similarly to non-steroidal anti-inflammatory drugs. The latter capabilities primarily were used in treating chronic inflammatory disorders. Dapsone has been investigated predominantly by in vitro methods aiming to get more insights into the effect of dapsone to inflammatory effector cells, cytokines, and/or mediators, such as cellular toxic oxygen metabolism, myoloperoxidase-/halogenid system, adhesion molecules, chemotaxis, membrane-associated phospholipids, prostaglandins, leukotrienes, interleukin-8, tumor necrosis factor α, lymphocyte functions, and tumor growth. Moreover, attention has been paid to mechanisms by which dapsone mediates effects in more complex settings like impact of lifespan, stroke, glioblastoma, or as anticonvulsive agent. Additionally, there are some dermatological investigations in human being using dapsone and its metabolites (e.g., leukotriene B₄-induced chemotaxis, ultraviolet-induced erythema). It could be established that dapsone metabolites by their own have anti-inflammatory properties. Pharmacology and mechanisms of action are determining factors for clinical use of dapsone chiefly in neutrophilic and/or eosinophilic dermatoses and in chronic disorders outside the field of dermatology. The steroid-sparing effect of dapsone is useful for numerous clinical entities. Future avenues of investigations will provide more information on this fascinating and essential agent.

Indomethacin-related leukocytoclastic vasculitis: a case report and review of literature

Leukocytoclastic vasculitis (LCV) is a small-vessel vasculitis with a reported incidence rate of 30 cases per million persons per year. It usually presents as a palpable purpuric skin rash on legs, though any part of the body can be affected. LCV rash may have an associated burning sensation or pain and in some cases may involve internal organs. In some cases, LCV rash may present as nodules, recurrent ulcerations or asymptomatic lesions. The diagnosis of LCV is usually made on skin biopsy. Etiological triggers may not be identified in as many as half of the cases. Treatment is usually conservative and includes identification and removal or treatment of the etiological trigger except in cases with internal organ involvement where systemic steroids and immunosuppressant may be necessary. In this article we present a case of indomethacin-associated LCV that improved with discontinuation of the offending agent.

Health-Related Quality of Life in Patients Poststroke: Dapsone versus Placebo

Background:

Stroke is the second leading cause of death in the world and the main cause of long-term disability in Western countries. Evaluating health-related quality of life (HRQOL) in patients who have survived a stroke provides a more complete picture of the effects of different interventions in a patient's condition. Dapsone has been shown to have neuroprotective effects during the acute phase of stroke.

Objective:

To evaluate HRQOL in patients who received dapsone versus placebo after stroke.

Methods:

This was an observational pilot study of 21 patients who randomly received dapsone or placebo during the acute phase of a stroke. HRQOL was evaluated with the Stroke-Specific Quality of Life (SSQOL) questionnaire 6 months after the stroke.

Results:

There was no significant difference in the total SSQOL score 6 months after a stroke between patients who received dapsone or placebo (3.41 vs 3.19; p = 0.434). Patients who received dapsone had higher mean values for 9 of the 12 domains of the SSQOL than patients who received placebo. However, the difference was not statistically significant. The highest score for the patients who received dapsone was in the self-care domain. Overall SSQOL scores were lower in women than in men (p < 0.01).

Conclusion:

SSQOL was slightly better for patients who received dapsone, showing a possible improvement in their functional level. More prospective, randomized, and placebo-controlled studies with a larger number of patients are needed to confirm these results.

Ocular Behçet disease: current therapeutic approaches

PURPOSE OF REVIEW

To alert physician to timely recognition and current treatment of recurrent hypopyon iridocyclitis or panuveitis in ocular Behçet disease (OBD).

RECENT FINDINGS

Interferon-α, rituximab, intravitreal triamcinolone, and biological response modifiers by tumor necrosis factor inhibitors such as infliximab and adalimumab are being used increasingly for the treatment of severe sight-threatening ocular inflammation including retinal vasculitis and cystoid macular edema (CME).

SUMMARY

Biological agents offer tremendous potential in the treatment of OBD. Given that OBD predominantly afflicts the younger adults in their most productive years, dermatologist, rheumatologist, internist, or general practitioners supervising patients with oculo-articulo-oromucocutaneous syndromes should be aware of systemic Behçet disease. Early recognition of ocular involvement is important and such patients should strongly be instructed to visit immediately an ophthalmologist, as uveitis management differs from extraocular involvements with high ocular morbidity from sight-threatening complications due to relapsing inflammatory attacks in the posterior segment of the eye. A single infliximab infusion should be considered for the control of acute panuveitis, whereas repeated long-term infliximab infusions were proved to be more effective in reducing the number of episodes in refractory uveoretinitis with faster regression and complete remission of CME.

Innovative use of dapsone

After synthesis of dapsone (4,4' diaminodiphenylsulfone) in 1908, the compound was known exclusively in chemistry. Following the epoch-making discovery of the antimicrobial potential for sulfonamides emerged, the sulfone class was included in the medical armamentarium. The therapeutic role of sulfones related to both pathogen-caused diseases and chronic inflammatory dermatoses has led to extensive use in dermatology. At present dapsone is the only sulfone congener available for clinical practice. The sulfone is used in rifampin-based multiple-drug regiments to treat multibacillary and paucibacillary leprosy and to treat Pneumocystis jiroveci pneumonia and prevent toxoplasmosis in individuals with AIDS. In dermatology, dapsone is the preferred drug for treating dermatitis herpetiformis (Duhring's disease) and is useful in the management of a broad range of chronic inflammatory entities, especially autoimmune bullous disorders. With proper administration and monitoring, the sulfone should be considered a useful and safe agent.

Severe leukocytoclastic vasculitis secondary to the use of a naproxen and requiring amputation: a case report

INTRODUCTION

Leukocytoclastic vasculitis (also known as hypersensitivity vasculitis and cutaneous necrotizing vasculitis) can present with various manifestations, which often delays the diagnosis and treatment. In order to show the importance of the early recognition of leukocytoclastic vasculitis, we present a case which occurred secondary to the use of a common pharmaceutical, naproxen. We were unable to find a case of leukocytoclastic vasculitis secondary to naproxen in the literature.

CASE PRESENTATION

We present the case of a 33-year-old African American woman with below the knee and bilateral digital gangrene from hypersensitivity vasculitis secondary to the non-steroidal anti-inflammatory medication naproxen.

CONCLUSION

This is an original case report focusing on the rheumatologic management of leukocytoclastic vasculitis. However, other specialties, such as internal medicine, dermatology, infectious disease, general surgery and pathology, can gain valuable information by reviewing this case report. Reporting a case of leukocytoclastic vasculitis secondary to treatment with naproxen will advance our understanding of this disease etiology by adding yet another non-steroidal anti-inflammatory drug to the list of potential causes of leukocytoclastic vasculitis.

Dapsona como alternativa no tratamento de urticária crônica não responsiva a anti-histamínicos

FUNDAMENTOS: A urticária crônica é dermatose que interfere negativamente na qualidade de vida de seus portadores. O tratamento clássico com anti-histamínicos muitas vezes é ineficaz. OBJETIVO: Avaliar a eficácia e a segurança do uso da dapsona no tratamento da urticária crônica não responsiva a anti-histamínicos. METÓDOS: Realizou-se estudo retrospectivo mediante a revisão de prontuários de pacientes atendidos em ambulatório especializado em urticária entre novembro de 1996 e março de 2007. RESULTADOS: Foram avaliados 20 pacientes com urticária crônica de difícil controle, que receberam tratamento com dapsona na dose de 100mg/dia. Associados à dapsona, foram mantidos anti-histamínicos em altas doses, que, isoladamente, não controlavam os sintomas. Quatorze pacientes (70%) responderam com melhora do quadro, observada tanto na diminuição ou desaparecimento das lesões quanto na redução do prurido; três (15%) não obtiveram nenhum sucesso com a medicação; e três (15%) tiveram o tratamento suspenso em decorrência de efeitos colaterais. CONCLUSÃO: Neste estudo, conclui-se que a dapsona é opção segura e eficaz para pacientes com urticária crônica grave não responsiva a anti-histamínicos.

Prospective randomized non-blinded clinical trial on the use of dapsone plus antihistamine vs. antihistamine in patients with chronic idiopathic urticaria

BACKGROUND

Treatment of chronic idiopathic urticaria (CIU) is difficult.

OBJECTIVE

The purpose of this study was to evaluate the efficacy and safety of dapsone in CIU.

METHODS

The response to dapsone was evaluated in 65 CIU patients with a randomized, two armed study: 3-month dapsone + desloratadin and 3-month desloratadin. All were followed for up to 3 months and 3 months after; all took desloratadine 10 mg daily throughout the study. The primary measure of efficacy was a daily urticaria activity score (UAS) of weal numbers and itch (maximum score, 42 per week).

RESULTS

Sixty-five patients completed the randomized 3-month trial medication. Mean reduction in UAS from baseline at 3 months was 7 [95% confidence interval (95% CI), 6.92-7.08] for active group and 5.77 (95% CI, 5.47-6.08) for control subjects (P < 0.001). The reduction in visual analogue score (VAS) at 3 months for active group (mean, 2.58; 95% CI, 2.33-2.83) and control subjects (mean, 2.55; 95% CI, 2.38-2.73) was also significant (P < 0.001). The reduction of UAS and VAS at 3 months compared between active group and control subjects showed no significant difference. Mean reduction in UAS from the end of the study at 3 months after was 1.16 and -4.8 for active and control subjects, respectively. These results were compared with each other, and it was statistically significant (P <or= 0.05).

LIMITATIONS

No placebo was used. The study was not blinded. Lack of blinding may have led to bias. The follow-up period was short.

CONCLUSION

This study shows that dapsone leads to a persistent decrease in VAS and UAS and is associated with complete remission in some patients.

[Disulone and hepatosiderosis]

BACKGROUND

Disulone (dapsone + iron oxalate) is a sulfone used in the treatment of numerous skin diseases. We report two cases of hepatosiderosis secondary to long-term administration of Disulone.

PATIENTS AND METHODS

Case n degrees 1. A 51-year-old man was treated with Disulone for a neutrophilic skin disease. After 17 years of treatment, elevated serum ferritin and free iron with hemolysis were found. Liver biopsy confirmed hepatosiderosis. A diagnosis of genetic hemochromatosis was ruled out by the absence of C282Y mutation of the HFE gene. Case n degrees 2. A 52-year-old man receiving Disulone for dermatitis herpetiformis for 25 years presented elevated serum ferritin and free iron with hemolysis. Hepatic iron overload was confirmed by liver biopsy. The absence of C282Y mutation (HFE gene) ruled out a diagnosis of genetic hemochromatosis.

DISCUSSION

In our two cases, hepatosiderosis was noted after long-term administration of Disulone. This complication has been reported only rarely. In murine models, a relationship was found between prolonged administration of dapsone and hepatic iron overload as revealed by hemolysis. Although it is difficult to extrapolate this relationship to humans with any certainty, our patients had also chronic hemolysis and iron overload secondary to administration of Disulone. Moreover in France, dapsone is marketed in combination with iron oxalate, with the attendant risk of iron overload. These cases raise the question of the need for serum ferritin analysis during Disulone therapy.

Dapsone suppresses human neutrophil superoxide production and elastase release in a calcium-dependent manner

BACKGROUND

Dapsone (4,4'-diaminodiphenyl sulphone) is a powerful therapeutic tool in many skin diseases including neutrophilic dermatoses. The drug has an outstanding therapeutic efficacy against many skin diseases characterized by neutrophil-rich infiltrates; however, mechanisms of its action are poorly understood.

OBJECTIVES

We investigated the effects of dapsone on respiratory and secretory functions of human neutrophils triggered by the chemotactic peptide N-formyl-L-methionyl-L-leucyl-L-phenylalanine (fMLP), the physiological agonist C5a, and phorbol myristate acetate (PMA).

METHODS

Human neutrophils were isolated from venous blood obtained from healthy donors. We detected extracellular production of superoxide (O(2) (-)) by cytochrome C reduction assay, and intracellular production of O(2) (-) by flow cytometry. Neutrophil elastase release was measured by the cleavage of the specific elastase substrate N-methoxysuccinyl-Ala-Ala-Pro-Val-p-nitroanilide. Measurement of cytosolic free calcium concentration was performed using the calcium-reactive fluorescence probe, Fluo-3.

RESULTS

Dapsone suppressed intra- and extracellular production of O(2) (-) and elastase release triggered by fMLP and C5a, but not by PMA. Both fMLP and C5a signalled the above pathways by inducing calcium influx, but PMA functions bypassed calcium influx. Dapsone was capable of antagonizing the induction of calcium influx.

CONCLUSIONS

These findings suggest that one mechanism of the anti-inflammatory action of dapsone is inhibition of calcium-dependent functions of neutrophils including release of tissue-damaging oxidants and proteases in the affected skin.

Drug bioactivation, covalent binding to target proteins and toxicity relevance

A number of therapeutic drugs with different structures and mechanisms of action have been reported to undergo metabolic activation by Phase I or Phase II drug-metabolizing enzymes. The bioactivation gives rise to reactive metabolites/intermediates, which readily confer covalent binding to various target proteins by nucleophilic substitution and/or Schiff's base mechanism. These drugs include analgesics (e.g., acetaminophen), antibacterial agents (e.g., sulfonamides and macrolide antibiotics), anticancer drugs (e.g., irinotecan), antiepileptic drugs (e.g., carbamazepine), anti-HIV agents (e.g., ritonavir), antipsychotics (e.g., clozapine), cardiovascular drugs (e.g., procainamide and hydralazine), immunosupressants (e.g., cyclosporine A), inhalational anesthetics (e.g., halothane), nonsteroidal anti-inflammatory drugs (NSAIDSs) (e.g., diclofenac), and steroids and their receptor modulators (e.g., estrogens and tamoxifen). Some herbal and dietary constituents are also bioactivated to reactive metabolites capable of binding covalently and inactivating cytochrome P450s (CYPs). A number of important target proteins of drugs have been identified by mass spectrometric techniques and proteomic approaches. The covalent binding and formation of drug-protein adducts are generally considered to be related to drug toxicity, and selective protein covalent binding by drug metabolites may lead to selective organ toxicity. However, the mechanisms involved in the protein adduct-induced toxicity are largely undefined, although it has been suggested that drug-protein adducts may cause toxicity either through impairing physiological functions of the modified proteins or through immune-mediated mechanisms. In addition, mechanism-based inhibition of CYPs may result in toxic drug-drug interactions. The clinical consequences of drug bioactivation and covalent binding to proteins are unpredictable, depending on many factors that are associated with the administered drugs and patients. Further studies using proteomic and genomic approaches with high throughput capacity are needed to identify the protein targets of reactive drug metabolites, and to elucidate the structure-activity relationships of drug's covalent binding to proteins and their clinical outcomes.

Idiopatic angioedema treated with dapsone

The most commonly identified causes of angioedema are medications, allergens and physical agents, but most cases of angioedema are idiopathic. Treatment depends on identification of the causative agent and, especially when the mechanism is not identified, on the clinicians knowledge and experience with innovative therapeutic regimens.

CASE REPORT

A 48-year-old man presented with a 3-month history of recurrent severe episodes of angioedema affecting the lips, tongue and throat. A fiberoptic examination revealed laryngeal edema during some episodes. He did not report abdominal pain, nausea or vomiting. No precipitating factors were identified. The patient was not receiving angiotensin-converting enzyme inhibitors. For the previous 4 years, the patient had been receiving levothyroxine for autoimmune thyroiditis. There was no history of facial palsy or hereditary angioedema.

ALLERGY STUDY

Skin prick test with aeroallergens, food, latex, Anisakis and patch test to a standard series (true test) were negative. Laboratory investigations revealed normal complete blood count (CBC), erythrocyte sedimentation rate, urinalysis, blood biochemistry, serum protein electrophoresis and serum immunoglobulins. IgE concentration was 30 UI/ml. Antiperoxidase antibodies were positive (535 UI/ml). Antinuclear antibodies serum immune complexes and rheumatoid factor were negative. Complement study during acute and asymptomatic periods revealed normal values of C1 esterase inhibitor, C1q, C3, C4, functional activity of C1 inhibitor and CH50. No pathologic findings were observed in a lip biopsy. The patient was treated with sedating and nonsedating H1 antihistamines and corticosteroids (prednisone 30 mg/day for 3 months) with no clinical improvement and treatment with 50 mg of dapsone daily was started. Glucose 6 phosphate dehydrogenase deficiency had previously been ruled out. The patient improved and antihistamine and corticoid treatment was withdrawn 1 month after starting the dapsone regimen. No episodes of angioedema appeared during the subsequent year. No reductions in hematologic parameters or adverse events were detected. Dapsone may be an alternative drug in extreme cases of idiopathic angioedema in patients with poor response to conventional therapy.

Systemic lupus erythematosus vasculitis: A current therapeutic overview

The development of systemic lupus erythematosus (SLE) vasculitis is of prognostic value. The earlier the vasculitis is treated, the better the prognosis for SLE. Cutaneous vasculitis is common in SLE, whereas visceral vasculitis is rare. Skin SLE vasculitis is successfully treated with antimalarials, but its discontinuation may result in an SLE flare even among patients in remission. When visceral SLE vasculitis is encountered, or when a disease state is perceived to be life-threatening, a more aggressive therapy is warranted. A combination of medications, plasmapheresis, and intravenous immunoglobulin treatment, along with high-dose steroids and cytotoxic drugs, are typically employed in the treatment of severe SLE vasculitis. Finally, patients with SLE vasculitis may benefit from a number of autoimmune disease therapies currently under investigation, such as switching cytokine responses from Th1 to Th2, and the manipulation of toll-like receptors, chemokines, and FcR receptors. Specific B-cell therapies (eg, anti-Blys, B-cell depletion) may also emerge as potential treatments for SLE vasculitis.

Dapsone Therapy for Malaria During Pregnancy

The need to consider using dapsone in pregnant women for its antimalarial activity is becoming greater in areas where Plasmodium falciparum resistance to chloroquine and pyrimethamine-sulfadoxine is rapidly increasing. Dapsone in combination with other antimalarials might provide a valuable alternative for both treatment and prophylaxis. This review assesses the clinical pharmacology of dapsone and its adverse drug reactions in relation to haemolysis, glucose-6-phosphate dehydrogenase (G6PD) deficiency, blood dyscrasias and methaemoglobinaemia. Studies are summarised reporting its use in leprosy, dermatological and other conditions, and malaria, in relation to maternal and infant outcomes. A total of 924 pregnancies were identified during which dapsone therapy was taken. Only limited data are available and this precludes a meaningful quantitative benefit-risk analysis. Mild degrees of haemolysis consistently occur with continued therapy, although adverse effects may be less likely with intermittent treatment, as most reported adverse effects have occurred with long-term use of dapsone. There are a number of gaps in knowledge where more data are needed. These include no data on pharmacokinetics in pregnancy and whether these are altered with co-administration of chlorproguanil. Potential complications in women with severe anaemia are unknown and there is no information on haemolytic effects in women or the fetus with G6PD deficiency. The use of dapsone in HIV-infected women in malarious areas could carry increased risks because of the immunosuppressive actions of the drug. Trials of dapsone therapy in pregnancy should be considered in malarious areas where there is good reason for its deployment. Controlled trials have provided data on maternal tolerance, and dapsone in combination with other antimalarial drugs can offer clear benefit in terms of improved birthweight. The use of dapsone combinations should be considered when no good alternative is available and the threat of malaria is the greater risk.

Sweet's syndrome: a review of current treatment options

Sweet's syndrome was originally described in 1964 by Dr Robert Douglas Sweet as an 'acute febrile neutrophilic dermatosis'. The syndrome is characterized by pyrexia, elevated neutrophil count, painful red papules, nodules, plaques (which may be recurrent) and an infiltrate consisting predominantly of mature neutrophils that are diffusely distributed in the upper dermis. In addition to skin and mucosal lesions, Sweet's syndrome can also present with extra-cutaneous manifestations. Sweet's syndrome can be classified based upon the clinical setting in which it occurs: classical or idiopathic Sweet's syndrome, malignancy-associated Sweet's syndrome and drug-induced Sweet's syndrome. Systemic corticosteroids have been considered the 'gold standard' for the treatment of patients with Sweet's syndrome; in addition, treatment with topical and/or intralesional corticosteroids may be effective as either monotherapy or adjuvant therapy. However, spontaneous resolution of the symptoms and lesions has occurred in several patients with Sweet's syndrome for whom disease-specific therapeutic intervention was not initiated and in some of the patients with drug-induced Sweet's syndrome after withdrawal of the dermatosis-causing medication. Oral therapy with either potassium iodide or colchicine typically results in rapid resolution of Sweet's syndrome symptoms and lesions; therefore, in patients with Sweet's syndrome who have a potential systemic infection or in whom corticosteroids are contraindicated, it is reasonable to initiate treatment with these agents as a first-line therapy. Indomethacin, clofazimine, dapsone, and cyclosporine have also been effective therapeutic agents for managing Sweet's syndrome. However, indomethacin and clofazimine appear less effective than corticosteroids, potassium iodide, and colchicine. Appropriate initial and follow-up laboratory monitoring is necessary when treating with either dapsone or cyclosporine because of the potential for severe adverse drug-associated effects. Systemic antibacterials with activity against Staphylococcus aureus frequently result in partial improvement of Sweet's syndrome lesions when they are impetiginized or secondarily infected. In some patients with dermatosis-associated bacterial infections, organism-sensitive specific systemic antibacterials have been helpful in the management of their Sweet's syndrome. Although patients with hematologic malignancy-associated Sweet's syndrome often receive cytotoxic chemotherapy agents and antimetabolic drugs for the treatment of their underlying disorder, these agents are seldom used solely for the management of the symptoms and lesions of Sweet's syndrome. The treatment of patients with Sweet's syndrome with either etretinate or interferon-alpha have been reported as single case reports; both patients had improvement of not only their Sweet's syndrome lesions, but also their associated hematologic disorder.