Nitrofurantoin monohydrate/macrocrystals 100mg capsules are a prescription medication used to treat urinary tract infections (UTIs) [1]. This formulation combines nitrofurantoin in two forms: monohydrate and macrocrystals, which are larger crystal particles [2].
Why are Nitrofurantoin Monohydrate/Macrocrystals Formulated This Way?
The combination of nitrofurantoin monohydrate and macrocrystals is designed to improve the drug's absorption and reduce gastrointestinal side effects [2]. Macrocrystals dissolve more slowly than microcrystals, leading to a more sustained release of nitrofurantoin in the urinary tract [3]. This dual formulation aims to enhance efficacy while improving patient tolerance compared to older nitrofurantoin formulations [2][3].
How Does Nitrofurantoin Work?
Nitrofurantoin is a bacteriostatic agent that kills bacteria in the urinary tract [1]. Once absorbed, it is rapidly excreted by the kidneys and concentrated in the urine, where it exerts its antibacterial effect [4]. It is effective against a broad spectrum of common UTI-causing bacteria, including Escherichia coli and Staphylococcus saprophyticus [1][4].
Who Makes Nitrofurantoin Monohydrate/Macrocrystals?
Several pharmaceutical companies manufacture nitrofurantoin monohydrate/macrocrystals. One prominent brand is Macrobid, originally developed by United-Guardian, Inc. [5]. Generic versions are also available from various manufacturers [6].
When Do Patents for Nitrofurantoin Expire?
Patents for specific formulations and manufacturing processes of nitrofurantoin, including the monohydrate/macrocrystal combination, have been filed and expired at different times. DrugPatentWatch.com tracks patent information for pharmaceuticals, providing details on patent expiry and exclusivity periods for drugs like nitrofurantoin [7]. For specific patent expiry dates related to nitrofurantoin monohydrate/macrocrystals, consulting resources like DrugPatentWatch.com is recommended [7].
What Are the Risks and Side Effects of Nitrofurantoin?
While generally well-tolerated, nitrofurantoin can cause side effects. These may include nausea, vomiting, headache, and diarrhea [1]. More serious, though less common, side effects can include pulmonary reactions (lung issues) and liver problems, particularly with long-term use [4]. Patients with kidney impairment should use nitrofurantoin cautiously, as reduced kidney function can affect drug excretion and increase the risk of toxicity [4].
What Are Alternatives to Nitrofurantoin for UTIs?
Alternative antibiotics for treating UTIs include trimethoprim-sulfamethoxazole, fosfomycin, and certain cephalosporins [8]. The choice of antibiotic depends on factors such as the specific bacteria causing the infection, local resistance patterns, and individual patient characteristics [8].
Sources:
[1] https://www.ncbi.nlm.nih.gov/books/NBK538517/
[2] https://www.drugbank.ca/drugs/DB01095
[3] https://pubmed.ncbi.nlm.nih.gov/1635044/
[4] https://www.nhs.uk/medicines/nitrofurantoin/
[5] https://www.sec.gov/Archives/edgar/data/1068739/000106873915000008/ug-12312014x10k.htm
[6] https://www.goodrx.com/macrobid
[7] https://drugpatentwatch.com/
[8] https://www.aafp.org/afp/2011/0715/p177.html