Trimethoprim-sulfamethoxazole dosing

DS, double strength SS, single strength TMP, trimethoprim TMP-SMX, trimethoprim-sulfamethoxazole. °Dosing internals for normal renal function. 

Streptococcus gentamicin (5 mg/kg per day, dosing based on serum levels) Alternative Therapies Trimethoprim-sulfamethoxazole (TMP-SMX) 10-20 mg/kgTMP IV per day in divided doses every 6-8 hours or meropenem Standard Therapy TMP-SMX Rash, Stevens-Johnson syndrome, bone marrow suppression, nausea/vomiting, hepatotoxicity 14-21... 

Trimethoprim- sulfamethoxazole 8-10 mg/kg per day of trimethoprim component in 2 doses Nausea, vomiting, anorexia, rash, urticaria S Increasing pneumococcal resistance contraindicated in children under 2 months... 

Trimethoprim-sulfamethoxazole (or trimethoprim alone) is a second-line oral agent that may be used for patients who do not tolerate tetracyclines and erythromycin or in cases of resistance to these antibiotics. The adult dose is usually 800 mg sulfamethoxazole and 160 mg trimethoprim twice daily. 

Antibiotics shorten the duration of diarrhea, decrease the volume of fluid lost, and shorten the duration of the carrier state (see Table 39-3). A single dose of oral doxycycline is the preferred agent. In children younger than 7 years of age, trimethoprim-sulfamethoxazole, erythromycin, and furazolidone can be used. In areas of high tetracycline resistance, fluoroquinolones are effective. 

Trimethoprim-sulfamethoxazole is given in doses of 15 to 20 mg/kg/day (based on the trimethoprim component) as three to four divided doses for the treatment of PCP. Treatment duration is typically 21 days but must be based on clinical response. 

Trimethoprim-sulfamethoxazole IV or orally 15-20 mg/kg/day as trimethoprim component in 3-4 divided doses for 21 days0 (Al) or... 

Trimethoprim-sulfamethoxazole is the preferred therapy for both primary and secondary prophylaxis of PCP in adults and adolescents. The recommended dose in adults and adolescents is one double-strength tablet daily. 

Trimethoprim-sulfamethoxazole 4-6 mg/kg (of the trimethoprim component) every 12 hours + metronidazole 30 mg/kg in three to four divided doses or clindamycin 10-30 mj kj day in three to four divided doses0... 

Acute uncomplicated cystitis Escherichia coli Staphylococcus saprophyticus 1. Trimethoprim-sulfamethoxazole x 3 days (A, 1)° 2 Fluoroquinolone x 3 days (A II)0 3. Nitrofurantion x 7 days (B, l)° 4. /)Lactams x 3 days (E, III)0 Short-course therapy more effective than single dose /J-factams as a group are not as effective in acute cystitis than trimethoprim-sulfamethoxazole or the fluoroquinolones0... 

Short-course therapy (3-day therapy) with trimethoprim-sulfamethoxazole or a fluoroquinolone (e.g., ciprofloxacin, levofloxacin, or norfloxacin) is superior to single-dose therapy for uncomplicated infection and... 

Single-dose or short-course therapy with trimethoprim-sulfamethoxazole has been used effectively, and prolonged courses of therapy are not necessary for the majority of patients. 

In women who experience symptomatic reinfections in association with sexual activity, voiding after intercourse may help prevent infection. Also, self-administered, single-dose prophylactic therapy with trimethoprim-sulfamethoxazole taken after intercourse has been found to significantly reduce the incidence of recurrent infection in these patients. 

Mercaptopurine [6-MP] (Purinethol) [Antineoplastic/ Antimeta lite] Uses Acute leukemias, 2nd-line Rx of CML NHL, maint ALL in children, immunosuppressant w/ autoimmune Dzs (Crohn Dz) Action Antimetabolite, mimics hypoxanthine Dose Adults. 80-100 mg/mVd or 2.5-5 mg/kg/d maint 1.5-2.5 mg/kg/d Peds. Per protocol X w/ renal/hepatic insuff on empty stomach Caution [D, ] Contra Severe hepatic Dz, BM suppression, PRG Disp Tabs SE Mild hematotox, mucositis, stomatitis, D rash, fever, eosinophilia, jaundice. Hep Interactions T Effects W/ allopurinol T risk of BM suppression W/ trimethoprim-sulfamethoxazole X effects OF warfarin EMS May falsely T glucose OD May cause NA and liver necrosis symptomatic and supportive Meropenem (Merrem) [Antibiotic/Carbapenem] Uses lntra-abd Infxns, bacterial meningitis Action Carbapenem X cell wall synth, a [3-lactam Dose Adults. 1 to 2 g IV q8h Peds. >3 mo, <50 kg 10-40 mg/kg IV q 8h in renal insuff Caution [B, ] Contra [3-Lactam sensitivity Disp Inj 500 mg, 1 g SE Less Sz potential than imipenem D, thrombocytopenia Interactions T Effects W/ probenecid EMS Monitor for signs of electrolyte disturbances and... 

Note that in addition to the adverse events due to trimethoprim the combination trimethoprim-sulfamethoxazole may cause all of the untoward reactions associated with sulfonamides. In HIV positive patients the incidence of rashes can increase to 50%. Desensibilisation with increasing doses of co-trimoxazole has been successful. 

The frequency of relapse and the risk of renal damage determine the need for on-demand therapy or prophylactic therapy. In intercourse-related UTI in sexually active women single dose prophylactic therapy was shown to be effective. One dose of trimethoprim ( sulfamethoxazole) or nitrofurantoin is effective, inexpensive and unlikely to allow the emergence of resistant bacteria. 

Trimethoprim-sulfamethoxazole (TMP-SMX) was introduced as a fixed dose combination in 1968. Trimethoprim was added to sulfamethoxazole to synergisti-cally and sequentially inhibit bacterial synthesis of tetrahydrofolic acid. The combination was also designed to delay development of bacterial resistance. Sulfamethoxazole was selected in part because it is a congener of the frequently used sulhsoxazole but exhibits slower enteric absorption and urinary excretion. Sulfamethoxazole has a half-life similar to that of trimethoprim. 

The most common adverse effects of lamivudine seen at doses used to treat HBV are mild they include headache, malaise, fatigue, fever, insomnia, diarrhea, and upper respiratory infections. Elevated alanine aminotransferase (ALT), serum lipase, and creatine kinase may also occur. The safety and efficacy of lamivudine in patients with decompensated liver disease have not been established. Dosage adjustment is required in individuals with renal impairment. Coadministration of trimethoprim-sulfamethoxazole decreases the renal clearance of lamivudine. 

The starting dose as well as dose adjustment in therapy are made according to guidelines fixed in the treatment protocols. For pneumocystis carinii pneumonia prophylaxis, trimethoprim-sulfamethoxazole is administered on three consecutive days per week, with the largest possible interval in reference to the weekly methotrexate application. This is done to account for the theoretical enhancement of the antifolic activity of methotrexate by co-administered trimethoprim-sulfamethoxazole (72,73). Because several reports have suggested an improved outcome with bedtime administration, 6-MP is commonly administered in the evening hours (74,75). Also, 6-MP should not be given in combination with milk because the xanthine oxidase (XO) activity contained in milk decreases the bioavailability of 6-MP (76,77,78). 

Trimethoprim- sulfamethoxazole Synergistic combination of folate antagonists blocks purine production and nucleic acid synthesis Bactericidal activity against susceptible bacteria Urinary tract infections Pneumocystis jiroveci pneumonia toxoplasmosis nocardiosis Oral, IV renal clearance (half-life 8 h) dosed every 8-12 h t formulated in a 5 1 ratio of sulfamethoxazole to trimethoprim Toxicity Rash, fever, bone marrow suppression, hyperkalemia... 

The combination of clindamycin and primaquine is an alternative regimen in the treatment of pneumocystosis, particularly mild to moderate disease. This regimen offers improved tolerance compared with high-dose trimethoprim-sulfamethoxazole or pentamidine, although its efficacy against severe pneumocystis pneumonia is not well studied. 

Atovaquone is an alternative therapy for P jiroveci infection, although its efficacy is lower than that of trimethoprim-sulfamethoxazole. Standard dosing is 750 mg taken with food twice daily for 21 days. Adverse effects include fever, rash, nausea, vomiting, diarrhea, headache, and insomnia. Serious adverse effects appear to be minimal, although experience with the drug remains limited. Atovaquone has also been effective in small numbers of immunocompromised patients with toxoplasmosis unresponsive to other agents, although its role in this disease is not yet defined. 

Doxycycline is commonly used for moderate to severe acne vulgaris. It is more effective and produces less resistance than tetracycline. The initial dose is 100 or 200 mg daily, followed by 50 mg daily as a maintenance dose after improvement is seen. Doxycycline maybe given with food, but it is more effective when taken 30 minutes before meals. / Minocycline is also commonly used for moderate to severe acne vulgaris. It is more effective than tetracycline. It is dosed similar to doxycycline (100 mg/day or 50 mg twice daily) and on an indefinite basis in selected patients. Minocycline has the most reported adverse effects of the tetracyclines, some of which may be serious. Trimethoprim-sulfamethoxazole (or trimethoprim alone) is a second-line oral agent that may be used for patients who do not tolerate tetracyclines and erythromycin or in cases of resistance to these antibiotics. The adult dose is usually 800 mg sulfamethoxazole and 160 mg trimethoprim twice daily. Clindamycin use is limited by diarrhea and the risk of pseudomembranous colitis. 

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