Dapsone causing

The combination of pyrimethamine plus dapsone causes a higher incidence of blood dyscrasias than pyrimethamine alone in particular, the occurrence of agranulocytosis increases and even deaths have been reported (SEDA-13, 812) (SEDA-18, 287). 

Leprosy, also referred to as Hansen s disease, is caused by the bacterium Mycobacterium leprae. Although rare in colder climates, this disease may be seen in tropical and subtropical zones. Dapsone and clofazimine (Lamprene) are the two drags currently used to treat leprosy. The leprostatic drugs are listed in the Summaiy Drug Table Leprostatic Dragp. 

This drug is used cautiously in patients with peripheral vascular disease, neuropathy, chronic pancreatitis, or impaired liver function. Didanosine is a Pregnancy Category B drug and is used cautiously during pregnancy and lactation. There may be a decrease in the effectiveness of dapsone in preventing Pneumocystis carinii pneumonia when didanosine is administered with dapsone Use of didanosine with zalcitabine may cause additive neuropathy. Absorption of didanosine is decreased when it is administered with food. 

Dapson RW. Macromolecular changes caused by formalin fixation and antigen retrieval. Biotech. Histochem. 2007 82 133-140. 

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... 

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. 

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. 

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. 

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. 

Choice of antimicrobial follows automatically from the clinical diagnosis because the causative organism is always the same, and is virtually always sensitive to the same drug, e.g. meningococcal septicaemia (benzylpenicillin), some haemolytic streptococcal infections, e.g. scarlet fever, erysipelas (benzylpenicillin), typhus (tetracycline), leprosy (dapsone with rifampicin). 

Methaemoglobinaemia may be induced by oxidising drugs sulphonamides, nitrites, nitrates (may also occur in drinking water), primaquine, -caine local anaesthetics, dapsone, nitrofurantoin, nitroprusside, vitamin K analogues, chlorates, aniline and nitrobenzene. In the rare instance of there being urgency, methylene blue 1 mg/kg slowly i.v. benefits within 30 min. (Ascorbic acid competes directly with the chemical cause but is inadequate in severe cases, which are the only ones that need treatment.)... 

Dapsone (alone or in combination with pyrimethamine) can cause methemoglobinemia and hemolytic anemia. These complications tend to be dose-related and are more often encountered in G6PD-deficient subjects (SEDA-18, 287). 

Methemoglobinemia toxicity is caused by several aromatic amines, including aniline and dapsone. and is a re.sult oftlie bioconversion of the aromatic amine to its A/-hydroxy... 

Common causes of fixed eruptions are ampicillin, aspirin, barbiturates, dapsone, metronidazole, NSAIDs, oral contraceptives, phenolphthalein, phenytoin, quinine, sulfonamides, and tetracyclines. 

---