Dapsone Rifampin

Several drugs closely related to the sulfonamides have been used effectively in the long-term treatment of leprosy. The most widely used is dapsone (diaminodiphenylsulfone). Like the sulfonamides, it inhibits folate synthesis. Resistance can emerge in large populations of M leprae, eg, in lepromatous leprosy, if very low doses are given. Therefore, the combination of dapsone, rifampin, and clofazimine is recommended for initial therapy. Dapsone may also be used to prevent and treat Pneumocystis jiroveci pneumonia in AIDS patients. 

The worldwide incidence of leprosy (Hansen s disease) has plummeted by nearly 90% to -534,000. The cornerstone of this global elimination strategy is the provision of effective multidrug chemotherapy, namely dapsone, rifampin, and clofazimine (Table 47-1), to all leprosy patients in the world. The success of the strategy is evident by the end of 2003, over half of the countries considered endemic for leprosy in 1985 had achieved disease elimination (i.e., a prevalence rate of <1 case per 10,000 inhabitants). 

Drugs that may be affected by probenecid include acyclovir allopurinol barbiturates benzodiazepines clofibrate dapsone dyphylline methotrexate NSAIDs pantothenic acid penicillamine rifampin sulfonamides sulfonylureas zidovudine salicylates. 

Deravirdine (Rescnptor) [Antiretroviral/NNRTI] Uses HIV Infxn Action Nonnucleoside RT inhibitor Dose 400 mg PO tid Caution [C, ] CDC recommends HIV-infected mothers not to breast-feed (transmission risk) w/ renal/hepatic impair Contra Use w/ drugs dependent on CYP3A for clearance (Table VI-8) Disp Tabs SE Fat redistribution, immune reconstitution synd, HA, fatigue, rash, T transaminases, N/V/D Interactions T Effects W/ fluoxetine T effects OF benzodiazepines, cisapride, clarithromycin, dapsone, ergotamine, indinavir, lovastatin, midazolam, nifedipine, quinidine, ritonavir, simvastatin, terfena-dine, triazolam, warfarin effects W/ antacids, barbiturates, carbamazepine, cimetidine, famotidine, lansoprazole, nizatidine, phenobarbital, phenytoin, ranitidine, rifabutin, rifampin effects OF didanosine EMS Use of benzodiazepines and CCBs should be avoided may cause a widespread rash located on upper body and arms OD May cause an extension of nl SEs symptomatic and supportive Deferasirox (Exjade) [Iron Chelator] Uses Chronic iron overload d/t transfusion in pts >2 y Action Oral iron chelator Dose Initial 20 mg/kg... 

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. 

Rifampin (see earlier discussion) in a dosage of 600 mg daily is highly effective in lepromatous leprosy. Because of the probable risk of emergence of rifampin-resistant M leprae, the drug is given in combination with dapsone or another antileprosy drug. A single monthly dose of 600 mg may be beneficial in combination therapy. 

Dapsone (Avlosulfon) is a member of a class of chemical agents known as the sulfones. Dapsone is especially effective against M. leprae and is used with rifampin as the primary method of treating leprosy. Dapsone appears to exert its antibacterial effects in a manner similar to that of the sulfonamide drugs that is, dapsone impairs folic acid synthesis by competing with PABA in bacterial cells. Primary adverse effects associated with dapsone include peripheral motor weakness, hypersensitivity reactions (skin rashes, itching), fever, and blood dyscrasias, such as hemolytic anemia. 

A4 Acetaminophen, alfentanil, amiodarone, astemizole, cocaine, cortisol, cyclosporine, dapsone, diazepam, dihydroergotamine, dihydropyridines, diltiazem, ethinyl estradiol, gestodene, indinavir, lidocaine, lovastatin, macrolides, methadone, miconazole, midazolam, mifepristone (RU 486), paclitaxel, progesterone, quinidine, rapamycin, ritonavir, saquinavir, spironolactone, sulfamethoxazole, sufentanil, tacrolimus, tamoxifen, terfenadine, testosterone, tetrahydro-cannabinol, triazolam, troleandomycin, verapamil Barbiturates, carbamazepine, macrolides, glucocorticoids, pioglitazone, phenytoin, rifampin Erythromycin, 613-hydroxy cortisol... 

Leprosy (Hansen s disease) is caused by M- leprae. Bacilli from skin lesions or nasal discharges of infected patients enter susceptible individuals via the skin or respiratory tract. The World Health Organization recommends the triple drug regimen, dapsone, clofazimine, and rifampin (see p. 333) for 6 to 24 months. 

Clofazimine is used in the treatment of lepromatous leprosy. including dap.sone-resistant forms of the di.sca.se. In sidition to its antibacterial action, the drug appears to possess anti-inflammatory and immune-modulating effects that are of value in controlling neuritic complications and in suppressing erythema nodosum leprosum reactions associated with lepromatous leprosy. It is frequently used in combina-iion with other drugs, such as dapsone or rifampin. 

Dapsone is u.sed in the treatment of both lepromatous and tuberculoid types of lcpro.sy. Dapsone is used widely for all forms of leprosy, often in combination with clofazimine and rifampin. Initial treatment often includes rifampin with dap-.sone. followed by dapsone alone. It is also u.s to prevent the occurrence of multibacillary lcpro.sy when given prophy-lactically. 

Isoniazid is ineffective in the treatment of leprosy or M. avium complex infection. Lepromatous (multibacillary) leprosy is treated with dapsone, clofazimine, and rifampin for a minimum of 2 years, whereas tuberculoid (pauciba-cillary) leprosy is treated with dapsone and rifampin for 6 months. 

Explain the action of dapsone and rifampin on the immune system. 

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