In short
Nitrofurantoin, macrocrystalline is an antibacterial agent specific for urinary tract infections. It is the active substance in medicines such as Macrobid and Furabid, which are authorised products containing nitrofurantoin. The clinical research data includes one completed Phase 1 bioequivalence study in 32 healthy subjects comparing two prolonged-release capsule formulations.
Key points
- Nitrofurantoin, macrocrystalline is an antibacterial agent used specifically for urinary tract infections.
- One Phase 1 clinical trial in the EU registry investigated nitrofurantoin, with 32 healthy participants.
- The trial was a bioequivalence study comparing two 100 mg prolonged-release capsule formulations.
- The study measured pharmacokinetic parameters including Cmax and AUC to compare absorption.
- The trial status is completed, and it was conducted in a fed state with a replicate crossover design.
What is nitrofurantoin, macrocrystalline?
Nitrofurantoin, macrocrystalline is the full name for the macrocrystalline form of nitrofurantoin, an antibacterial agent that is specific for urinary tract infections. The chemical name of nitrofurantoin macrocrystals is 1-[[[5-nitro-2-furanyl]methylene]amino]-2,4-imidazolidinedione, with a molecular weight of 238.16. Nitrofurantoin appears in authorised medicines under trade names including Macrobid and Furabid.
How does nitrofurantoin, macrocrystalline work?
Nitrofurantoin is an antibacterial agent, meaning it works against bacteria that cause infections in the urinary tract. The macrocrystalline form of nitrofurantoin has slower dissolution and absorption than the monohydrate form, which affects how the drug is released in the body. In Macrobid capsules, 25% of the content is macrocrystalline nitrofurantoin, which dissolves more slowly, while the remaining 75% is nitrofurantoin monohydrate in a powder blend that forms a gel matrix upon exposure to gastric and intestinal fluids, releasing nitrofurantoin over time.
Which conditions is it used or studied for?
- Urinary tract infections — nitrofurantoin is an antibacterial agent specific for this type of infection.
- Healthy subjects — the registered clinical trial studied the substance in healthy volunteers to compare absorption of two formulations, not to treat a disease.
How is nitrofurantoin, macrocrystalline given?
Nitrofurantoin is given orally in the form of prolonged-release capsules. The registered trial used 100 mg prolonged-release capsules, and the product information for Macrobid describes hard gelatin capsules each containing 100 mg of nitrofurantoin. The trial was conducted in a fed state, with the dose administered after a standard breakfast.
What do the clinical trials show?
There is one clinical trial in the EU Clinical Trials Information System for nitrofurantoin, macrocrystalline. It is a Phase 1 bioequivalence study that has been completed. The study enrolled 32 healthy subjects and used a replicate crossover design to compare the rate and extent of absorption of a test formulation, NITROFURANTOIN 100 mg prolonged-release capsules from Iasis Pharma, against a reference formulation, Furabid 100 mg prolonged-release capsules from Amdipharm Limited.
The primary outcome measured pharmacokinetics, specifically the parameters Cmax (maximum plasma concentration), AUCtotal (total area under the concentration-time curve), and AUClast (area under the curve up to the last measurable concentration). These measurements compare how much of the drug reaches the bloodstream and how long it stays there, which is the standard way to assess whether two formulations are bioequivalent.
What side effects are known?
The supplementary source provided does not list side effects for nitrofurantoin, macrocrystalline, so this section is not included.