nitrofurantoin

Action and Spectrum

Actions and Spectrum: 

Action: 

Inhibition of Bacterial Cell Wall Synthesis: nitrofurantoin disrupts the production of bacterial cell walls through its ability to hinder the activity of multiple enzymes essential for cell wall synthesis. This disruption weakens the cell walls of susceptible bacteria, leading to cell death. 

Damaging Bacterial DNA: nitrofurantoin can also damage bacterial DNA by forming reactive intermediates that disrupt DNA replication and repair processes.  

Spectrum: 

Escherichia coli (E. coli): nitrofurantoin is highly effective against E. coli, which is the most common cause of UTIs. 

Enterococcus faecalis: nitrofurantoin exhibits activity against Enterococcus faecalis, a gram-positive bacterium that can cause UTIs. 

Drug Interaction

Adverse Reaction

Frequency not defined  

Fever 

Dizziness 

Clostridium difficile colitis 

Chest pains 

Drowsiness 

Fatigue 

Diarrhea 

Chills 

Dyspnea 

Exfoliative dermatitis 

Arthralgia 

Cyanosis secondary to methemoglobinemia 

Anorexia 

Cough 

Black Box Warning

Black Box Warning: 

None

Contraindication / Caution

Contraindication/Caution:  

• Hypersensitivity 
• History of hepatic dysfunction/cholestatic jaundice with nitrofurantoin 
• Pregnancy at term (38-42 weeks of gestation) 
• Neonates (<28 days) 
• Renal failure (anuria, oliguria, or CrCl <60 mL/min)

Cautions: 

• Risk of occasional hepatotoxicity and pulmonary toxicity 
• Renal impairment 
• Avoid long-term use in the elderly (may increase risk for pulmonary toxicity Acute/chronic pulmonary reactions (eg., cough, interstitial pneumonitis or fibrosis) reported 
• Bacterial superinfections may occur with prolonged treatment 
• Peripheral neuropathy may occur; risk may increase in patients diagnosed with anemia, diabetes, vitamin B deficiency, or electrolyte imbalance  

Pregnancy / Lactation

Pregnancy warnings:     

Pregnancy category: B 

Lactation: Excreted into human milk is known 

Pregnancy Categories:         

Category A: Studies that were well-controlled and met expectations revealed no risk to the fetus in either the first or second trimester. 

Category B: There were a lack of studies on pregnant women and no evidence of risk to the fetus in animal experiments.   

Category C: there was evidence of risk of adverse effects in animal reproduction studies, and no adequate evidence in human studies must take care of potential risks in pregnant women.    

Category D: adequate data with sufficient evidence of human fetal risk from various platforms, but despite the potential risk, and used only in emergency cases for potential benefits.   

Category X: Drugs listed in this category outweigh the risks over benefits. Hence these categories of drugs need to be avoided by pregnant women.    

Category N: There is no data available for the drug under this category

Pharmacology

Pharmacology:  

nitrofurantoin is an antibiotic medication commonly used to treat and prevent urinary tract infections (UTIs). 

Pharmacodynamics:  

nitrofurantoin acts by entering bacterial cells, where it undergoes a chemical reduction process. The reduced form of nitrofurantoin generates reactive intermediates that interfere with various bacterial enzymes, proteins, and ribosomal function. These actions inhibit bacterial growth and lead to cell death.  

Pharmacokinetics: 

Absorption 

The drug is well absorbed, macrocrystalline form of the drug absorbed more gradually due to gradual dissolution. 

Distribution 

The drug Crosses placenta, but not well distributed, The bound Protein of the drug is Approximately 60-90%.The volume of distribution of the drug is 0.8 L/kg. 

Metabolism 

nitrofurantoin is metabolized in the liver through various enzymatic processes, including reduction, acetylation, and glucuronidation. The metabolites formed are inactive and are eliminated in the urine. 

Excretion and Elimination 

The primary route of elimination for nitrofurantoin is renal excretion. The parent drug and its metabolites are eliminated primarily through the kidneys via glomerular filtration and active tubular secretion. Approximately 40-50% of the administered dose is excreted unchanged in the urine within 24 hours. 

Adminstartion

Administration:  

Oral administration by capsules & oral suspension in the prescribed dosage. 

Patient Information Leaflet

Patient information leaflet 

Generic Name: nitrofurantoin 

Why do we use nitrofurantoin?  

Treatment of uncomplicated urinary tract infections (UTIs): The drug is often prescribed as a first-line treatment for uncomplicated UTIs caused by susceptible bacteria, including Escherichia coli, Enterococcus species, Staphylococcus saprophyticus, and other pathogens commonly found in the urinary tract. 

Prophylaxis of recurrent urinary tract infections: The drug can be prescribed to prevent recurrent UTIs in individuals who experience frequent infections. It may be used in low doses for an extended period to suppress bacterial growth and reduce the risk of infection. 

Prevention of urinary tract infections during medical procedures: Before specific medical procedures, such as urological surgery or diagnostic procedures involving the urinary tract, nitrofurantoin might be prescribed as a preventive measure to reduce the risk of post-procedural infections.