Absorption<unk>  is well-absorbed when administered topically. It is rapidly absorbed when it is orally administered. Distribution<unk>  distributes into most body tissues as well as into sputum, vaginal fluid, and middle ear fluid. It also crosses the placenta. About 70% of the drug is bound to plasma proteins. Its Tmax (or time to reach maximum drug concentration in plasma) occurs 1 to 4 hours after oral administration. The mean serum half-life of<unk>  is 10 hours. However, the half-life of the drug noticeably increases in people with creatinine clearance rates equal to or less than 30 mL/minute. A half-life of 22–50 hours has been reported for people with creatinine clearances of less than 10 mL/minute. Metabolism<unk>  is metabolized in the human liver to at least 5 metabolites. These metabolites are the N4-acetyl-, N4-hydroxy-, 5-methylhydroxy-, N4-acetyl-5-methylhydroxy-sulfamethoxazole metabolites, and an N-glucuronide conjugate. The CYP2C9 enzyme is responsible for the formation of the N4-hydroxy metabolite. In vitro studies suggest<unk>  is not a substrate of the P-glycoprotein transporter. Excretion<unk>  is primarily renally excreted via glomerular filtration and tubular secretion. About 20% of the<unk>  in urine is the unchanged drug, about 15–20% is the N-glucuronide conjugate, and about 50–70 % is the acetylated metabolite.<unk>  is also excreted in human milk.
Sulfamethoxazole
Trimethoprim
Moxifloxacin
Phenoxymethylpenicillin
Penicillin
Streptomycin
Enrofloxacin
Minocycline