The main factors affecting the norfloxacin dose are the clinical condition being treated and the kidney or renal function of the patient. Norfloxacin is an antibiotic drug which may be used to treat urinary tract infections, prostatitis and uncomplicated gonorrhea caused by susceptible organisms. In most countries it is available by prescription only and may be known by different trade names, according to manufacturer.
Norfloxacin belongs to the class of antibiotics called fluoroquinolones, which also includes ciprofloxacin and moxifloxacin. They work by inhibiting the action of DNA gyrase, an enzyme involved in the production of bacterial DNA. By inhibiting the enzyme, norfloxacin renders the bacteria unable to reproduce in the body. Resistance has been reported in some bacteria, so the treating doctor may take a sample, such as urine, from the patient, to do a susceptibility culture in the laboratory.
The most common condition treated with norfloxacin is bladder or urinary tract infections caused by susceptible organisms, and the usual norfloxacin dose used is 400 mg twice daily. The duration of treatment with norfloxacin will depend on the severity of the infection. For uncomplicated infections, it may be given for only three days, whereas for more complicated infections it may be given for seven to ten, or even 21 days. When used to treat prostatitis the norfloxacin dose is also usually 400 mg twice daily, but is given for 28 days. For uncomplicated gonorrhea, a single dose of 800 mg may be given, but resistance has been found in many countries.
Patients with kidney or renal dysfunction may need to have their norfloxacin dose adjusted according to the severity thereof. The prescribing doctor may choose to lower the norfloxacin dose or increase the time between doses. Many elderly patients have reduced kidney function and the prescribing doctor should take this into consideration and adjust the norfloxacin dose accordingly.
Regardless of the norfloxacin dose prescribed, it is vital that the full course is completed, even if symptoms resolve before the course is finished. Failure to complete a full course of any antibiotic, including norfloxacin, may result in the production of resistant bacteria and difficulty in treating infections later on. Adverse effects may occur during treatment, including gastrointestinal side effects such as abdominal pain, nausea and vomiting, and central nervous system (CNS) effects such as drowsiness and confusion. Should any severe adverse effects be experienced while on treatment, medical attention should be sought.