Macrofuran - General Information
A urinary anti-infective agent effective against most gram-positive and gram-negative organisms. Although sulfonamides and antibiotics are usually the agents of choice for urinary tract infections, nitrofurantoin is widely used for prophylaxis and long-term suppression. [PubChem]
Pharmacology of Macrofuran
Macrofuran, a nitrofuran antibacterial agent, is available in microcrystalline and macrocrystalline form to treat urinary tract infections caused by many gram-negative and some gram-positive bacteria.
Macrofuran for patients
Patients should be advised to take Macrobid with food (ideally breakfast and dinner) to further enhance tolerance and improve drug absorption. Patients should be instructed to complete the full course of therapy; however, they should be advised to contact their physician if any unusual symptoms occur during therapy.
Patients should be advised not to use antacid preparations containing magnesium trisilicate while taking Macrobid.
Patients should be counseled that antibacterial drugs including Macrobid should only be used to treat bacterial infections. They do not treat viral infections (e.g., the common cold). When Macrobid is prescribed to treat a bacterial infection, patients should be told that although it is common to feel better early in the course of therapy, the medication should be taken exactly as directed. Skipping doses or not completing the full course of therapy may (1) decrease the effectiveness of the immediate treatment and (2) increase the likelihood that bacteria will develop resistance and will not be treatable by Macrobid or other antibacterial drugs in the future.
Antacids containing magnesium trisilicate, when administered concomitantly with nitrofurantoin, reduce both the rate and extent of absorption. The mechanism for this interaction probably is adsorption of nitrofurantoin onto the surface of magnesium trisilicate.
Uricosuric drugs, such as probenecid and sulfinpyrazone, can inhibit renal tubular secretion of nitrofurantoin. The resulting increase in nitrofurantoin serum levels may increase toxicity, and the decreased urinary levels could lessen its efficacy as a urinary tract antibacterial.
Drug/Laboratory Test Interactions
As a result of the presence of nitrofurantoin, a false-positive reaction for glucose in the urine may occur. This has been observed with Benedictís and Fehlingís solutions but not with the glucose enzymatic test.
Anuria, oliguria, or significant impairment of renal function (creatinine clearance under 60 mL per minute or clinically significant elevated serum creatinine) are contraindications. Treatment of this type of patient carries an increased risk of toxicity because of impaired excretion of the drug.
Because of the possibility of hemolytic anemia due to immature erythrocyte enzyme systems (glutathione instability), the drug is contraindicated in pregnant patients at term (38-42 weeks gestation), during labor and delivery, or when the onset of labor is imminent. For the same reason, the drug is contraindicated in neonates under one month of age.
Macrobid is also contraindicated in those patients with known hypersensitivity to nitrofurantoin.
Additional information about Macrofuran
Macrofuran Indication: For the treatment of infection of the urinary tract
Mechanism Of Action: Macrofuran inhibits bacterial acetyl-coenzyme A, interfering with the organism's carbohydrate metabolism. The drug also can disrupt bacterial cell wall formation.
Drug Interactions: Not Available
Food Interactions: Take with food.
Generic Name: Nitrofurantoin
Synonyms: Not Available
Drug Category: Anti-Infectives
Drug Type: Small Molecule; Approved
Absorption: Not Available
Toxicity (Overdose): Not Available
Protein Binding: 60%
Biotransformation: Not Available
Half Life: 0.3-1 hour
Dosage Forms of Macrofuran: Tablet Oral
Chemical IUPAC Name: 1-[(5-nitrofuran-2-yl)methylideneamino]imidazolidine-2,4-dione
Chemical Formula: C8H6N4O5
Nitrofurantoin on Wikipedia: https://en.wikipedia.org/wiki/Nitrofurantoin
Organisms Affected: Gram negative and gram positive bacteria