Cycloserine excretion

Other Infections. The slowly excreted sulfonamides (eg, sulfamethoxypyrida2ine, sulfadimethoxine) are used for treatment of minor infections such as sinusitis or otitis, or for prolonged maintenance therapy. Soluble sulfonamides are sometimes used for proto2oal infections in combination with other agents. Pyrimethamine, combined with sulfonamides, has been used for toxoplasmosis or leishmaniasis, and trimethoprim with sulfonamides has been used in some types of malaria. In nocardiosis, sulfonamides have been used with cycloserine [68-41-7] (17). 

D-alanine that is involved in bacterial cell wall synthesis. Cycloserine is inhibitory to M. tuberculosis and active against Escherichia coli, S. aureus, and Enterococcus, Nocardia, and Chlamydia spp. It is used in the treatment of MDR tuberculosis and is useful in renal tuberculosis, since most of the drug is excreted unchanged in the urine. 

Cycloserine is readily absorbed orally and distributes throughout body fluids including the cerebrospinal fluid. The concentrations of cycloserine in tissues, body fluids, and the cerebrospinal fluid are approximately equal to the plasma level. Cycloserine is partially metabolized, and 60 to 80% is excreted unchanged by the kidney. 

Cycloserine This orally effective tuberculostatic agent appears to antagonize the steps in bacterial cell wall synthesis involving D-alanine. It distributes well throughout body fluids, including the CSF. Cycloserine [sye kloe SER een] is metabolized, and both parent and metabolite are excreted in urine. Accumulation occurs with renal insufficiency. Adverse effects involve CNS disturbances epileptic seizure activity may be exacerbated. Peripheral neuropathies are also a problem. 

Hobson determined that cycloserine is well absorbed when administered orally. About 65 was excreted unchanged in the urine while 35 was metabolized to unknown substances. 

When given orally, 70—90% of cycloserine is rapidly absorbed. Cycloserine is distributed throughout body fluids and tissues. CSF concentrations are comparable to those in plasma. About 50% of a parenteral dose of cycloserine is excreted unchanged in the urine in the first 12 hours a total of 65% is recoverable in the active form over a period of 72 hours. Very little of the antibiotic is metabolized. The drug may reach toxic concentrations in patients with renal insufficiency it is removed from the circulation by hemodialysis. 

Cycloserine is an antibiotic (antimycobacterial drug) duly obtained from S. orchidaceus. It is a chemical analogue of D-alanine. It belongs to the second-line tuberculostatic drug, and it also acts as an inhibitor of cell-wall synthesis. It is readily absorbed via the oral administration, and subsequently gets distributed amongst different body tissues and the cerebrospinal fluids (CSF). It is found to be excreted mostly unaltered in urine via glomerular filtration. 

Mattila MJ, Nieminen E, Tiitinen H. Serum levels, urinary excretion, and side-effects of cycloserine in the presence of isoniazid and p-aminosalicylic acid. Scand J Respir Dis (1969) 50, 291-300. 

Venho VMK, Koskinen R The effect of p3n zinamide, rifampicin and cycloserine on the blood levels and urinary excretion of isoniazid Ann Clin Res (1971) 3,277-80. 

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