Nitrofurantoin , sold under the trade name Macrobid among others, is an antibiotic used to treat bladder infections. It is not effective for kidney infection. It was taken by mouth.
Common side effects include nausea, loss of appetite, diarrhea, and headaches. Rarely numbness, lung problems, or liver problems can occur. It should not be used in people with kidney problems. Although it seems generally safe during pregnancy it should not be used near shipping. It works by slowing growth rather than killing bacteria.
Nitrofurantoin was first sold in 1953. It is a List of Essential Medicines of the World Health Organization, the most effective and safe medicines needed in the health system. It is available as a generic drug. The cost of wholesale in developing countries is between 0.005 and 0.46 USD doses. In the United States about 60 USD for 10 days of treatment.
Video Nitrofurantoin
Medical use
Current uses include treatment of uncomplicated urinary tract infections (UTI) and prophylaxis of UTI in people who are susceptible to recurrent UTIs.
Increasing bacterial antibiotic resistance to other commonly used agents, such as fluoroquinolones and trimethoprim/sulfamethoxazole, has led to increased interest in using nitrofurantoin. Several trials comparing nitrofurantoin with other commonly used agents suggest that these drugs produce the same healing rate for uncomplicated UTIs. The efficacy of nitrofurantoin in treating UTIs combined with low levels of bacterial resistance to these agents makes it one of the first-line agents to treat uncomplicated UTIs as recommended by the Infectious Diseases Society of America and the European Society for Microbiology and Infectious Diseases.
Nitrofurantoin is not recommended for the treatment of pyelonephritis, prostatitis and intra-abdominal abscess, due to very poor tissue penetration and low blood levels.
Antibacterial Activity
Nitrofurantoin telah terbukti memiliki aktivitas yang baik terhadap:
- E. coli Staphylococcus saprophyticus
- Staphylococcus negatif coagulase Enterococcus faecalis Staphylococcus aureus
- Streptococcus agalactiae Citrobacter spesies Klebsiella spesies Bacillus subtilis spesies
It is used in the treatment of infections caused by these organisms.
Many or all of the following genera strains are resistant to nitrofurantoin:
- Enterobacter
- Klebsiella
- Proteus
- Pseudomonas
Antibiotic susceptibility testing should always be done to further explain the resistance profiles of certain infectious bacterial strains.
Pregnancy
Nitrofurantoin is a B pregnancy category. This is one of the few drugs commonly used in pregnancy to treat UTI. Other drugs used for UTIs in pregnancy include cephalexin, amoxicillin, and pivmecillinam. This drug should not be given to women late in pregnancy because of the potential risk of hemolytic anemia in newborns, as newborns have not developed the enzymatic pathway required for glutathione metabolism and drugs can cause oxidative damage to red blood cells. Newborns of women given this drug at the end of pregnancy have a higher risk of developing neonatal jaundice.
Several trials on the safety and teratogenicity of nitrofurantoin in pregnancy have shown mixed results. A retrospective study in 2009 states that some birth defects, such as hypoplastic left heart syndrome, ophthalmic malformations, cleft lip and palate, and atrial septal defect, are more common in neonates exposed to nitrofurantoin during pregnancy. A meta-analysis of four of the twenty-two studies available on nitrofurantoin safety found no increased risk. A case-control study in 1998 found an increased risk of craniosynostosis after exposure to "nitrosatable" drugs. A newer population-based cohort study of 2013 using women enrolled in the Norwegian Recipes Database and linking the subject to the birthrate database, however, found no increased risk of major malformations in neonates born to women taking nitrofurantoin early in pregnancy. Many studies that show an increased risk of nitrofurantoin have limitations and rely on patient retraction of antibiotics they consume during pregnancy rather than objective data, which may lead to recall bias. Nevertheless, in light of this contradictory data, the American College of Obstetrics and Gynecology (ACOG) recommends the use of antibiotics only for proper indication and for the shortest effective duration.
Maps Nitrofurantoin
Adverse effects
The most common side effects with nitrofurantoin are nausea, headache, and flatulence. Less common adverse events (less than 1% of those taking the drug) include:
- Gastrointestinal: diarrhea, dyspepsia, abdominal pain, constipation, vomiting
- Neurological: dizziness, drowsiness, amblyopia
- Respiratory: acute pulmonary hypersensitivity reaction
- Allergies: pruritus, urticaria
- Dermatologic: hair loss
- Miscellaneous: fever, chills, malaise
Patients should be informed that the color of brown nitrofurantoin urine; this is really harmless.
Some of the more serious but rare side effects of nitrofurantoin have been a concern. These include pulmonary reactions, hepatotoxicity, and neuropathy.
Pulmonary Toxicity
Pulmonary toxicity caused by nitrofurantoin can be categorized into acute, subacute, and chronic lung reactions. Acute and subacute reactions are suspected due to hypersensitivity reactions and are often lost when the drug is stopped. Acute reactions are estimated to occur in about one in 5000 women using the drug. These reactions usually develop 3-8 days after the first dose of nitrofurantoin, but can occur from several hours to several weeks after starting the drug. Symptoms include fever, dyspnea, chills, cough, pleuritic chest pain, headache, back pain, and epigastric pain. Chest X-rays will often show unilateral or bilateral infiltrates similar to pulmonary edema. Treatments include nitrofurantoin termination, which should result in improvement of symptoms within 24 hours.
Chronic pulmonary reactions caused by nitrofurantoin include diffuse interstitial pneumonitis, pulmonary fibrosis, or both. This unusual reaction can occur 1 month to 6 years after starting the drug and is usually associated with a total lifetime dose. This reaction manifests with progressive breathlessness. It is important to recognize nitrofurantoin as a possible cause of symptoms and stop the drug when suspicion of lung side effects arises because it can be reversible if the drug is stopped early.
Hepatotoxicity
Liver reactions, including hepatitis, cholestatic jaundice, chronic active hepatitis, and liver necrosis, are rare. The onset of chronic active hepatitis can be dangerous, and patients should be monitored regularly for changes in biochemical tests that will indicate liver damage. These reactions usually occur after exposure to the drug for more than 6 weeks. If signs of liver failure are observed in patients taking nitrofurantoin, the drug should be discontinued. Challenging back with the drug in the future is not recommended, as the reaction may have a component of hypersensitivity and relapse when the drug is continued.
Neuropathy
Neuropathy is a rare side effect of using nitrofurantoin. The patient may experience numbness and tingling in a glove pattern, which may or may not improve after discontinuation of the drug.
Contraindications
Nitrofurantoin is contraindicated in patients with decreased renal function (CrCl & lt; 60 ml/min) due to systemic accumulation and subterapeutic levels achieved in the urinary tract. However, a retrospective chart review shows the data for this cutoff is very thin and cuts CrCl & lt; 40 ml/min would be more appropriate. Many of the severe side effects of this drug are more common in older people and those with renal impairment, as this causes the drug to be preserved in the body and reaches higher systemic levels. Thus, this drug is not recommended for elderly populations according to AGS Beer 2012 criteria.
Nitrofurantoin is also contraindicated in infants up to the age of one month, because they have an immature enzyme system in their red blood cells (glutathione instability), so nitrofurantoin should not be used because it can cause hemolytic anemia. For the same reason, nitrofurantoin should not be administered to pregnant women after 38 weeks of pregnancy. Nitrofurantoin is contraindicated in patients with glucose-6-phosphate dehydrogenase deficiency because of the risk of intravascular haemolysis that causes anemia.
Pharmacology
The organism is said to be susceptible to nitrofurantoin if its minimum inhibitory concentration is 32 Âμg/ml or less. Peak blood concentration of nitrofurantoin after oral dose of nitrofurantoin 100 mg, less than 1? G/ml and may not be detected. Bioavailability is about 90% and urine excretion is 40% tissue penetration negligible; drugs are well concentrated in urine: 75% of the doses are rapidly metabolized by the liver, but 25% of the doses excreted in the urine are unchanged, reliably reaching the level of 200? g/ml or more. In dog studies, most urinary excretion is through glomerular filtration with some tubular secretions. There is also increased tubular absorption by acidification of urine. However, the activity of nitrofurantoin also depends on pH and the average inhibitory concentration increases sharply with an increase in pH above 6. Nitrofurantoin can not be used to treat infections other than simple cystitis.
At concentrations achieved in urine (& gt; 100 μg/ml), nitrofurantoin is bactericidal. It is bacteriostatic to the most susceptible organisms at concentrations less than 32 μg/ml.
Nitrofurantoin and quinolone antibiotics are mutually antagonistic in vitro . It is not known whether this is clinically significant, but the combination should be avoided.
Resistance to nitrofurantoin may be chromosome or plasmid-mediated and involves inhibition of nitrofuran reductase. Getting resistant at E. coli continues to be rare.
Nitrofurantoin and its metabolites are excreted mainly by the kidneys. In renal impairment, the concentrations achieved in the urine may be subterapeutic. Nitrofurantoin should not be used in patients with creatinine clearance of 60 ml/min or less. However, retrospective chart reviews may show nitrofurantoin is not contraindicated in this population.
Formulation
There are two nitrofurantoin formulations.
- Macrocrystals - (Macrodantin, Furadantin) - 25, 50, or 100 mg capsules - taken once every 6 hours
- Monohydrate/macrocrystals - (Macrobid) - 100 mg capsule - taken once every 12 hours or 2 times a day (written on prescription as BID, which is the last part of the MacroBID trade name). This is a 75% monohydrate and 25% macrocrystals.
Action mechanism
Nitrofurantoin is concentrated in urine, leading to higher levels and more effectively in the urinary tract than in tissues or other compartments. With oral doses of 100 mg, plasma levels are usually less than 1 Âμg/ml while in urine reaches 200 Âμg/ml.
The mechanism of action is unique and complex. This drug works by destroying bacterial DNA, because its reduced form is very reactive. This is made possible by the rapid reduction of nitrofurantoin in bacterial cells by flavoprotein (nitrofuran reductase) to several reactive intermediates that attack ribosomal proteins, DNA, respiration, pyruvate metabolism and other macromolecules in the cell. Nitrofurantoin gives a greater effect on bacterial cells than mammalian cells because bacterial cells activate the drug more quickly. It is not known which nitrofurantoin action is primarily responsible for its bactericidal activity. The broad mechanism of action for these drugs may be responsible for the low development of resistance to their effects, as they affect many different processes that are important for bacterial cells.
History
Nitrofurantoin has been available for the treatment of urinary tract infection (UTI) since 1953.
Animal feed
Residues from the breakdown of antibiotics of nitrofurans, including nitrofurantoin, have been found in chickens in Vietnam, China, Brazil, and Thailand. The European Union prohibits the use of nitrofuran in animals that produce food by classifying it in ATTACHMENT IV (list of pharmacologically active substances with no fixed residual maximum limit) of Council Regulation 2377/90. The US Food and Drug Administration (FDA) has banned furaltadone since February 1985 and withdrew approval for other nitrofuran drugs (except for some topical uses) in January 1992. The use of furazolidone and nitrofurazone was topically banned in 2002. Australia banned the use of nitrofuran in food production in 1992. Japan does not allocate MRL for nitrofuran which leads to the application of "zero tolerance or no residual standard". In Thailand, the Ministry of Health issued in 2001 No Proclamation. 231 MRL of veterinary drugs in foods not allocating MRL for nitrofuran. The Department of Agriculture and Cooperatives has banned the import and use of furazolidone and nitrofurazone in animal feeds in 1999 that expanded to all nitrofurans in 2002. Some nitrofuran metabolites, such as furazolidone, furaltadone and nitrofurazone, cause cancer or genetic damage to rats.
Society and culture
Cost
It is available as a generic drug. Wholesale costs are 0.005 and 0.46 USD doses. In the United States, the fee is $ 60 USD for 10 days of treatment.
Trade name
Nitrofurantoin is marketed under many names in countries around the world.
References
External links
- nitrofurantoin (Rx) - Medscape
Source of the article : Wikipedia
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