Ethionamide Cycloserine

Malone RS, Fish DN, Spiegel DM, et al. The effect of hemodialysis on cycloserine, ethionamide, /rara-aminosalicylate, and clofazimine. Chest 1999 116 984-990. 

In general, INH, pyrazinamide, ethionamide, and cycloserine penetrate the cerebrospinal fluid readily. Patients with CNS TB are often treated for longer periods (9 to 12 months). Extrapulmonary TB of the soft tissues can be treated with conventional regimens. TB of the bone is typically treated for 9 months, occasionally with surgical debridement. 

Drugs of choice are isoniazid, rifampin, ethambutol, along with streptomycin and pyrazinamide. Less well tolerated, second-line agents include p-aminosal-icylic acid, cycloserine, viomycin, ka-namycin, amikacin, capreomycin, ethionamide. 

Drugs that may interact with cycloserine include alcohol, ethionamide, and isoniazid. 

Mycobacterium tuberculosis Isoniazid + rifampin + ethambutol + pyrazinamide Streptomycin, moxifloxacin, amikacin, ethionamide, cycloserine, PAS, linezolid... 

Aminosalicylic acid - Cycloserine - Ethambutol - Ethionamide - Isoniazid - Pyrazinamide Rifampin... 

A number of drugs—aminosalicylic acid [a mee noe sal i SIL ik], ethionamide [e thye on AM ide], cycloserine [sye kloe SER een]— are considered second-line drugs because they are no more effective than the first-line agents and their toxicities are often more serious. Streptomycin, the first antibiotic effective in the treatment of tuberculosis, has been discussed wth the aminoglycosides (see p. 314). Its action is directed against extracellular organisms. 

Alycobocteriiim leprae (leprosy) Actinomycetes dapsone + rifampicin clofazimine ethionamide or cycloserine... 

Alternative or reserve drugs are used where there are problems of drug intolerance and bacterial resistance. They are in this class because of either greater toxicity or of lesser efficacy and include ethionamide (gastrointestinal irritation, allergic reactions), capreomycin (nephrotoxic), and cycloserine (effective but neurotoxic). Quinolone antibiotics such as ciprofloxacin and the more recently introduced macrolides such as clarithromycin and azithromycin also have useful activity against mycobacteria. 

Ethionamide and its sulfoxide metabolite are cleared hepati-cally, so dosing is unchanged. °p-Aminosalicylic acid is converted largely to metabolites prior to renal elimination these metabolites may accumulate in renal failure. For patients on hemodialysis, the usual 12-hour dosing interval for p-aminosalicylic acid granules seems to be safe. Dialysis will remove the metabolites. Serum concentration monitoring must be performed for cycloserine to avoid dose-related toxicities in renal failure patients... 

A fluoroquinolone cycloserine capreomycin or kanamycin or amikacin efliionamide para-aminosalicyclic acid clofazimine Clarithromycin or azithromycin ethionamide ... 

M. tuberculosis Isoniazid -1- rifampin - -pyrazinamide -1- ethambutol or streptomycin Moxifloxacin or gatifloxacin cycloserine capreomycin kanamycin amikacin ethionamide clofazimine aminosalicylic acid... 

M. avium complex Clarithromycin or azithromycin -1- ethambutol with or without rifabutin Rifabutin rifampin ethionamide cycloserine moxifloxacin or gatifloxacin... 

It may be used alone to clear the sputum of mycobacteria within a span of 12 weeks in many cases, but bacterial resistance usually takes place in 35% of cases, and thus leading to frequent relapses. Therefore, it is employed in combination with isoniazid, pyrazinamide, cycloserine or ethionamide-such relapses are uncommon. 

Antimycobacterials and related drugs Aminosalicylic acid (PAS), Capreomycin, Clofazimine, Cycloserine, Dapsone, Ethambutol, Ethionamide, Isoniazid, Methaniazide, Protionamide, Pyrazinamide, Rifabutin, Rifampicin (Rifampin), Rifamycin, Rihipentine, Rihiximin... 

The major problem in tuberculosis therapy is the buildup of resistance to the drug in use. Attempts at overcoming this difficulty took the form of additives such as substituted phenothiazines and acridines to retard emergence of resistance to INH 3i qj, combinations of drugs such as INH plus ethionamide, pyrazinamide, cycloserine or ethoxide . The biophysical aspects of the interaction of amino acridines with nucleic acids were reviewed 3,... 

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