Trimethoprim with

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). 

One possible interpretation of this type of rule is the enzyme ligand binding of trimethoprim with bacterial DHFR and chicken liver DHFR. (17,18)... 

As said before, on the basis of their mechanisms of action combinations of trimethoprim with a sulfon-... 

Dapsone and pyrimethamine should be used in patients that cannot tolerate sulfamethoxazole/trimethoprim with a CD4 count less than... 

Take trimethoprim with food if stomach upset occurs... 

A-2) It is common to combine trimethoprim with mlfonamide in the treatment of certain infections. The sulfonamide acts on bacteria to inhibit folate fonnation in bacteria by competitively inhibiting PABA incorporation (fig. 10.4). The trimethoprim acts on the dihydrofolate reductase step (between 7,8 dihydrofolate and 5,6,7,8 THF). Apparently, trimethoprim has a more damaging effect on bacteria and protozoans than it has on humans. 

Hoigne R, Klein U, Muller U. Results of four-week course of therapy of urinary tract infections a comparative study using trimethoprim with sulfamethoxazole (Bactrim Roche) and trimethoprim alone In Hejzlar M, Semonsky M, Masak S, editors. Advances in Antimicrobial and Antineoplastic Chemotherapy. Munchen-Berhu-Wien Urban and Schwatzenberg, 1972 1283. 

In a literature review, the authors found two other cases of bone marrow suppression after treatment with methotrexate and trimethoprim with full recovery of both. This interaction is also listed in the British National Formulary 1997 (194,195). 

Tasker PR, MacGregor GA, de Wardener HE. Use of co-trimoxazole in chronic renal failure. Lancet. 1975 May 31 1(7918) 1216-8. Bourgault AM, Van Scoy RE, Brewer NS, Rosenow EC.Trimethoprim with sulfamethoxazole for treatment of Infection with Pneumocystis carinii in renal insufficiency. Chest. 1978 Jul 74(1) 91-2. 

Dissociation rate constants, spin lifetimes, and relaxation times in the complexes of trimethoprim with dihydrofolate reductase at 45 °C. 

Two reports describe serious hyperkalaemia, apparently caused by the use of trimethoprim with enalapril or quinapril in association with renal impairment. 

In a placebo-controlled study, 6 healthy subjects were given cimetidine 400 mg every 6 hours for 6 days, with a single 960-mg dose of co-trimox-azole (trimethoprim with sulfamethoxazole) on day 6. Although trimethoprim levels were consistently slightly higher in the presence of cimetidine, they were not significantly different. Cimetidine had no effect on the pharmacokinetics sulfamethoxazole. ... 

Trimethoprim, both aione and as co-trimoxazoie (trimethoprim with suifamethoxazoie) reduces the renai ciearance of iamivu-dine, zaicitabine and zidovudine, and therefore raises their pias-ma ieveis. However, the extent of the interaction does not usuaily appear to be ciinicaiiy significant in patients with normal renal function. No clinically significant adverse pharmacokinetic interaction occurs if didanosine is given with co-trimoxazole or trimethoprim. 

Two pregnancies were attributed to the use of trimethoprim with an oral contraceptive (unspecified) in the adverse reactions register of the CSM in the UK for the years 1968 to 1984 (a total of 61 cases were attributed to other antibacterials). Another survey of oral contraceptive failure identified one pregnancy due to trimethoprim (23 of a total of 137 cases were attributed to antibacterials), while an earlier survey attributed 3 cases of contraceptive failure to either co-trimoxazole or trimethoprim. One case with trimethoprim and one with trimethoprim plus nifrofurantoin are briefly mentioned in another report. ... 

Four patients taking tricyclic antidepressants (imipramine, clomipramine, dibenzepin) and one taking viloxazine relapsed into depression when they took co-trimoxazole (trimethoprim with sulfamethoxazole) for 2 to 9 days. The reasons are not known. Another patient treated for 5 years with alprazolam and imipramine for panic disorder and who had not had panic attacks for several months developed insomnia, anxiety and panic attacks within 6 days of starting to take co-trimoxazole. The panic... 

Fig. 6.16 CPK space-filling models of trimethoprim with the three IgE antibody-binding determinants shown in green, yellow, and blue, (a) The 3,4-dimethoxybenzyl determinant shown in green (b) 2,4-diamino-5-(3, 4 -dimethoxybenzyl)pyrimidine determinant shown in yellow, (c) the whole trimethoprim molecule shown in blue comprises the allergenic determinant for some antitrimethoprim IgE antibodies. See also Table 6.3...

In the absence of reactive heterocycles, trifluoromethylation occurs on the arene portion of the substrate, as shown in the reaction of trimethoprim with TFMS (eq 7). 

Figure 1 Dynamic processes in the complex of trimethoprim with Lactobacillus casei dihydrofolate reductase measured at 298 K. Reproduced with permission from Searle MS etal. (1988) Proceedings of the National Academy of Sciences of the USA 85 3787-3791.

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