Dapsone other

In general, aromatic primary amino moiety (i.e., Ar-NH2), as present in a host of sulphadrugs viz., succinyl sulphathiazole, sulphamethoxazole, sulphaphenazole and other potent pharmaceutical substances, for instance sodium or calcium aminosalicylate, isocarboxazid, primaquine phosphate, procainamide hydrochloride, procaine hydrochloride and dapsone react with sodium nitrite in an acidic medium to yield the corresponding diazonium salts as expressed below ... 

Antibiotics clarithromycin, erythromycin Others omeprazole, cisapride, dapsone, lavastatin... 

Dapsone, which was first proposed in 1941, possesses both bactericidal as weU as bacteriostatic activity with respect to Mycobacterium leprae and Mycobacterium tuberculosis. It is used to treat patients with herpetiform dermatitis. It is believed that the mechanism of its action consists of competitive inhibition of the enzyme dihydroprotease synthetase, which blocks synthesis of folic acid in microorganisms, allowing it to also be viewed as an analog of p-aminobenzoic acid. Synonyms of this drug are avosulfon, croysulfon and others. 

Other drugs Acetazolamide, acetosulfone, acetylcysteine, acitretin, allopurinol, aminoglutehimide, benzaflbrate, brompheniramine, calcium dobe-silate, chloropheniramine, chlorpropamide, colchicine, deferiprone, dapsone, flutamide, glibenclamide, hydroxychloroquine, mebhydro-lin, meprobamate, metapyrilene, methazolamide, metochlopramide, prednisone, promethazine, retinoic acid, riluzole, ritodrine, tolbutamide, yohimbine... 

Dapsone is approved for the treatment of an autoimmune blistering skin disease, dermatitis herpetiformis. This intensely pruritic eruption is characterized histologically by a dense dermal infiltration of neutrophils and subepidermal blisters. Other skin diseases in which dapsone is helpful are linear immunoglobulin A (IgA) dermatosis, subcorneal pustular dermatosis, leukocytoclastic vasculitis, and a variety of rarer eruptions in which neutrophils predominate, including some forms of cutaneous lupus erythematosus. 

Dapsone, combined with other antUeprosy agents like rifampin and clofazimine, is used in the treatment of both multibacillary and paucibacillary M. leprae infections. Dapsone is also used in the treatment and prevention of Pneumocystis carinii pneumonia in AIDS patients who are allergic to or intolerant of trimethoprim-sulfamethoxazole. 

Clofazimine is given to treat sulfone-resistant leprosy or to patients who are intolerant to sulfones. It also exerts an antiinflammatory effect and prevents erythema nodosum leprosum, which can interrupt treatment with dapsone. This is a major advantage of clofazimine over other antileprosy drugs. Ulcerative lesions caused by Mycobacterium ulcerans respond well to clofazimine. It also has some activity against M. tuberculosis and can be used as last resort therapy for the treatment of MDR tuberculosis. 

Buffering agents that are compounded with didanosine to counteract its degradation by gastric acid may interfere with the absorption of other drugs that require acidity (e.g., indinavir, delavirdine, ketoconazole, fluoroquinolones, tetracyclines, dapsone). An enteric-coated formulation Videx EC) that dissolves in the basic pH of the small intestine is not susceptible to these interactions. Ganciclovir and valganciclovir can increase blood levels of didanosine. The use of zalcitabine with didanosine is not recommended because that combination carries an additive risk of peripheral neuropathy. The combination of didanosine with stavudine increases the risk of pancreatitis, hepatotoxicity, and peripheral neuropa-... 

The answers are 484-k, 483-j. (Hardman, pp 1061—1062, 1682-1683.) Sulfonamides can cause acute hemolytic anemia. In some patients it may be related to a sensitization phenomenon, and in other patients the hemolysis is due to a glucose-6-phosphate dehydrogenase deficiency. Sulfamethoxazole alone or in combination with trimethoprim is used to treat UTIs. The sulfonamide sulfasalazine is employed in the treatment of ulcerative colitis. Dapsone, a drug that is used in the treatment of leprosy, and primaquine, an antimalarial agent, can produce hemolysis, particularly in patients with a glucose-6-phosphate dehydrogenase deficiency. 

Drug Interactions Zidovudine Probenecid Imipenem-cilastatin Dapsone Pentamidine Flucytosine Vincristine Vinblastine Adriamycin Amphotericin B TMP-SMX Other nucleoside analogues... 

Although the two forms of the enzyme have preferred substrates, there is overlap between them such that no substrate seems to be exclusively acetylated by one or the other. Some preferred NAT1 substrates are p-aminobenzoic acid and p-aminosalicylic acid and sulfanilamide, whereas preferred substrates for NAT2 include isoniazid, hydralazine, procainamide, and dapsone. 

Toxoplasmosis Lymph nodes many organs and tissues Pyrimethamine-sulfadiazine [see antimalarial drugs] other antibacterials [clindamycin] Trimethoprim-sulfamethoxazole another agent [azithromycin, clarithromycin, atovaquone, or dapsone]... 

Pyrimethamine may also be combined with other antimalarials such as artemisinin derivatives, but these regimens should only be used if the malarial parasites are not resistant to the specific drugs in the regimen.13 Pyrimethamine can also be combined with a sulfonamide drug such as dapsone, sulfadiazine, or sulfamethoxazole to treat protozoal infections that cause toxoplasmosis, or fungal infections that cause Pneumocystis pneumonia.These agents are administered orally. 

Charcoal does not bind iron, lithium, or potassium, and it binds alcohols and cyanide only poorly. It does not appear to be useful in poisoning due to corrosive mineral acids and alkali. Recent studies suggest that oral activated charcoal given alone may be just as effective as gut emptying followed by charcoal. Also, other studies have shown that repeated doses of oral activated charcoal may enhance systemic elimination of some drugs (including carbamazepine, dapsone, and theophylline) by a mechanism referred to as "gut dialysis."... 

Commonly used drugs (other than isoniazid) affected by NAT2 polymorphism were procainamide, hydralazine, dapsone, and sulfonamides with an increase of side effects in all cases. A selective substrate of NATl is -aminosalicylic acid (PAS), but its genetic variation was never clinically important (52). Because of such lack of importance, more attention is often paid to the fact that various industrial chemicals with carcinogenic potential, and mutagenic heterocyclic amines, are substrates of both N-acetyltransferases (53). The presence or absence of these transferases will determine some incidences of cancer (54). Attempts have been made to ascribe cancer incidences in different populations to acetyltransferase differences (55). 

Dapsone (4,4 -diaminodiphenylsulfone) has been widely used for phenotyping with respect to acetylation by NAT-2 however, the drug is also N-hydroxylated. Formation of the hydroxylamine metabolite by human liver microsomes was found to be selectively mediated by CYP3A (286) this led to the development of a zero- to eight-hour urinary metabolic recovery ratio approach [dapsone hydroxylamine (dapsone + dapsone hydroxylamine)] to quantitatively assess this pathway of metabolism (287,288). Subsequently, the trait measure has been applied as part of a cocktail approach (35) in a number of studies investigating the putative role of CYP3A as a risk factor in cancer (289-291) and other disease states (288,292,293). 

Some recent references for other used NAT2 phenotyping tests can be found for dapsone in Alhrevic (2003), O Neil (2000), Queiroz (1997), for sulphamet-hazine in Hadasova (1996) and Meisel (1997), and for procainamide in Okumura (1997) and Mongey (1999). 

Dapsone is an antileprosy drug. It is a very effective one too, especially when used in combination with two other drugs in a cocktail that can be simply drunk as an aqueous solution by patients in tropical countries without any special facilities, even in the open air. But there is a problem Dapsone is insoluble in water. 

DRUGS TO TREAT INFECTIONS OTHER ANTIBIOTICS Dapsone... 

Drugs that carry a definite risk of haemolysis in most G6PD deficient subjects include dapsone (and other sulphones), methylene blue, niridazole, nitrofurantoin, pamaquin, primaquine, quinolone antimicrobials, some sulphonamides. 

Dermatitis herpetiformis Dapsone is typically effective in 24 h, or sulfapyrldine. Prolonged therapy necessary, a gluten-free diet can help, Antipruritics locally as required. Not other sulphonamides benef dal effect not due to antimicrobial action. Methaemoglobinaemia may complicate dapsone therapy. 

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