Norfloxacin is a bactericidal agent used in human medicine in some broad-spectrum antibiotics and belongs to the group of drugs called gyrase inhibitors. Norfloxacin and other members of this group of active ingredients kill bacteria by inhibiting their gyrase enzyme. Preparations containing mainly or exclusively norfloxacin are used, among other things, to treat acute infections of the urinary tract (e.g., cystitis).
What is norfloxacin?
Due to its action as well as other properties, norfloxacin represents an antibiotic. The substance achieves its effect by inhibiting the bacteria‘s own enzyme gyrase. This is vital for bacteria, as it is essentially responsible for so-called DNA supercoiling. Norfloxacin therefore belongs to the gyrase inhibitor class of active ingredients. The closely related antibiotics levofloxacin and ofloxacin are also part of this class of active ingredients. In addition, norfloxacin is also classified as a fluoroquinolone. Preparations containing norfloxacin as the active ingredient are prescribed to treat acute or chronic urinary tract infections. Usually, the colorless to pale yellow active ingredient is prescribed in the form of film-coated tablets and taken orally by patients. In chemistry and pharmacology, norfloxacin is described by the molecular formula C 16 – H 18 – F – N 3 – O 3. This corresponds to a moral mass of 319.33 g/mol.
Pharmacologic Action
Norfloxacin has a potent bactericidal effect. It follows that it specifically and efficiently kills infectious bacteria. Typical of the gyrase inhibitor class of drugs, norfloxacin causes inhibition (inhibition) of the enzyme gyrase. This is a protein produced by the infectious bacteria themselves. They need it to shape the spatial orientation of their DNA. Due to the immense importance of gyrase for DNA supercoiling (ring-like shaping of DNA), bacteria are not viable for long after inhibition has been completed. They can no longer reproduce and die. Since norfloxacin is particularly effective against bacteria that cause urinary tract infections or gonorrhea (colloquially known as “gonorrhea”), the antibiotic is mainly used in this area. The active ingredient is usually used in monopreparations (drugs that rely on one active ingredient). Norfloxacin is rapidly absorbed from the gastrointestinal tract. It is then present in 25% of plasma proteins and has a half-life of between 5 and 7 hours. Because of the metabolic properties of norfloxacin, it is possible for an opiate test to show a false positive result.
Medical application and use
Norfloxacin is considered a broad-spectrum antibiotic. Thus, it is capable of killing a variety of different bacteria with high efficacy. According to its property as an antibiotic of the gyrase inhibitor class, norfloxacin is used to treat infectious diseases. There is an indication in complicated and uncomplicated, chronic or acute infections of the urinary tract. The drug can be used on both upper and lower urinary tract. However, complicated inflammation of the renal pelvis and inflammation of the kidneys themselves (complicated pyelonephritis) are excluded. In 2009, the European Medicines Agency and the German Federal Institute for Drugs and Medical Devices changed their risk-benefit assessment to the effect that there is no longer an indication for these diseases. The reason given was insufficient demonstrable efficacy in complicated pyelonephritis or renal pelvic inflammation. However, there is still an indication for urinary tract infections associated with surgical or urological procedures. Norfloxacin is also administered for kidney stones. Other typical indications for the antibiotic include female bladder infections, bacterial gastroenteritis and gonorrhea. Norfloxacin may also be prescribed to prevent possible blood poisoning that could occur in association with granulocytopenia. Norfloxacin is usually taken orally. The antibiotic is sold in tablet form and requires a prescription and a pharmacy.
Risks and side effects
Norfloxacin should not be taken if there is hypersensitivity (allergy) to the active ingredient. Also in case of allergy to other medicines of the same class of active ingredients (quinolo antibiotics z.B. levofloxacin, moxifloxacin, ciprofloxacin, or ofloxacin), a contraindication exists. This means that the drug must not be taken from a medical point of view because there is a contraindication. Such a contraindication also exists in pregnant women, children and adolescents, and during breastfeeding. In such cases, the drug must not be used. Norfloxacin must also not be taken if complications of the tendons (especially tendon sheath inflammation) have already occurred in connection with therapy with quinolo antibiotics. Norfloxacin may cause undesirable side effects. However, this is not mandatory. Most treatments pass without side effects. Studies found the following side effects:
- Leukopenia (low white blood cell count), neutropenia (low granulocyte count), an increase in liver enzymes, headache, drowsiness, abdominal pain, nausea, and skin rash occur frequently (in one to 10 people treated out of a total of 100).
- Occasionally (in less than one in 100 treated), treatment causes crystalluria (crystals in the urine), hemolytic anemia, fatigue, anxiety, nervousness and increased irritability, euphoria (greatly elevated mood), hallucinations, seizures, and hypersensitivity.
- Rarely (in less than one in 1,000 treated), inflammation of the intestines accompanied by fever and abdominal pain, and inflammation of the Achilles tendon.
- Very rarely (in less than one in 10,000 treated), the development of cardiac arrhythmias and a breakdown of liver cells or muscle tissue may occur.
