Bactrim - Trimethoprim

The combined use of sulfonamides or sulfones with dihydrofolate reductase inhibitors, such as trimethoprim Bactrim, Septra) or pyrimethamine Fansidar), s, a good example of the synergistic possibilities that exist in multiple-drug chemotherapy. This type of impairment of the parasite s metabolism is termed sequential blockade. Using drugs that inhibit at two different points in the same biochemical pathway produces parasite lethality at lower drug concentrations than are possible when either drug is used alone. 

Bactrim/forte (Roche)-comb. with trimethoprim... 

The diaminopyrimidines trimethoprim and pyrimethamine are synthetic, antibacterial drags and inhibitors of dihydrofolate reductase that are used both independently as well as in combination with sulfanilamides, in particular, with sulfamethoxazole (cotrimoxazole, bactrim, biseptol, sulfatrim, and many others). 

Oral suspension 40 mg trimethoprim and Various, Bactrim Pediatric 200 mg sulfamethoxazole/5 mL (Rx) (Roche), Septra (GlaxoSmithKline)... 

Trimethoprim (TMP)-Sulfamethoxazole (SMX) [Co-Trimoxa-zole] (Bactrim, Septra) Vancomycin (Vancocin, Vancoled)... 

Trimethoprim (TMP)-Sulfamethmazole (SMX) [Co-Trimoxazole] (Bactrim, Septra) [Antibiotic/Folate Antagonist] Uses un Rx prophylaxis, otitis media, sinusitis, bronchitis Action SMX T synth of dihydro-folic acid TMP T dihydrofolate reductase to impair protein synth Dose Adul. 1 DS tab PO bid or 5-20 mg/kg/24 h (based on TMP) IV in 3-4 doses P. jiroveci ... 

Trimethoprim-sulfamethoxazole [co-trimoxazole, TMP-SMZ] (generic, Bactrim, Septra, others)... 

In acute and chronic urinary tract infection, the combination of trimethoprim and sulfamethoxazole (Bactrim, Septra) exerts a truly synergistic effect on bacteria. The sulfonamide inhibits the utilization of p-amino-benzoic acid in the synthesis of folic acid (Figure 2.3), whereas trimethoprim, by inhibiting dihydrofolic acid reductase, blocks the conversion of dihydrofolic acid to tetrahydrofolic acid, which is essential to bacteria in the denovo synthesis of purines, pyrimidines, and certain amino acids. Because mammalian organisms do not synthesize folic acid and therefore need it as a vitamin in their daily diets, trimethoprim-sulfamethoxazole does not interfere with the metabolism of mammalian cells. 

Many other commonly used antibiotics can cause psychiatric symptoms, for example, clarithromycin (trade name, Biaxin)—which is frequently used to treat respiratory illness, ear infections, and skin infections—has been reported to cause mania in some patients. Metronidazole (trade name Flagyl), which is used to treat many types of infections—from parasites to vaginal infections and abscesses—has been reported to cause depression, agitation, confusion, hallucinations, and mania. Trimethoprim-sulfamethoxazole (trade names Bactrim and Septra)—which is used, for example, for bladder infections and sinus and ear infections—has been reported to cause delirium, psychosis, depression, and hallucinations in rare cases. The fluoroquinolone antibiotics—such as ciprofloxacin (trade name Cipro), levofloxacin (trade name Levaquin), ofloxacin (trade name Floxin), trovafloxacin (trade name Trovan), and others of this class—can cause psychiatric symptoms fairly often, including confusion, agitation, depression, insomnia, mania, paranoia, and psychosis. 

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. 

A widely available fixed combination is co-trimoxazole (Bactrim, Eusaprim, Septrin), which contains trimethoprim and sulfamethoxazole in a ratio of 1 5. Both trimethoprim and sulfamethoxazole have favorable and comparable pharmacokinetics and the combination is bactericidal (4). Synergy between trimethoprim and sulfonamides has conventionally been ascribed to sequential inhibition of dihydropteroate synthetase by sulfonamides (in competition with pora-aminobenzoic acid) and of dihydrofolate reductase by trimethoprim (in competition with dihydrofolate). However, sulfonamides in high concentrations also inhibit dihydrofolate reductase. Thus, an initial partial sequential blockade by trimethoprim (inhibition of dihydrofolate reductase) and sulfonamides (inhibition of dihydropteroate synthetase) leads to defective protein synthesis and cytoplasmic damage, which in turn results in marked increases in the uptake of both agents and double strength inhibition of dihydrofolate reductase (5). 

Horn B, Cottier P. Kreatininkonzentration im Serum vor und unter Behandlung mit Trimethoprim-Sulfamethoxazol. [Serum creatinine concentration prior to and following trimethoprim-sulfamethoxazole (Bactrim) treatment.] Schweiz Med Wochenschr 1974 104(49) 1809-12. 

Note Although trimethoprim has been known to elicit occasional adverse reactions by itself, it is most commonly used in conjunction with sulfamethoxazole (co-trimoxazole). The trade names for this combination are Bactrim Cotrim Septra. Please see co-trimoxazole for the specific reaction patterns and references... 

Bactrim co-trimoxazole, sulfamethoxazole, trimethoprim Benhex Cream lindane... 

Trenolone dexchlorpheniramine trimethoprim Abaprim, Alprim, Bactin, Bactrim, Idotrim, Ipral,... 

Resistant strains of P. acnes are emerging that may respond to jndicions nse of retinoids in combination with antibiotics. Commonly nsed topical antimicrobials in acne inclnde erythromycin, clindamycin (Cleocin-t), and benzoyl peroxide and antibiotic-benzoyl peroxide combinations (Benzamycin, Benzaclin, others). Other antimiaobials nsed in treating acne inclnde sulfacetamide (Klaron), sulfacetamide/sulfur combinations (Snlfacet-R), metronidawie (Metrocream, Metro-Gel, noritate), and azelaic acid (Azelex). Systemic therapy is prescribed for patients with more extensive disease and acne that is resistant to topical therapy. Effective agents inclnde tetracycline (snmycin, others), minocycline (MINO-CIN, others), erythromycin (ERYC, others), clindamycin (CLEOCIN), and trimethoprim-sulfamethoxazole (bactrim, others). Antibiotics nsnally are administered twice daily, and doses are tapered after control is achieved. 

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