The active ingredient in Macrodantin is nitrofurantoin macrocrystals.
Macrocrystals are larger crystals of the drug nitrofurantoin.
Nitrofurantoin macrocrystals are absorbed slower into your body than regular nitrofurantoin.
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Macrobid 100 milligram (mg) capsules contain 25 mg of nitrofurantoin macrocrystals and 75 mg of nitrofurantoin monohydrate.
Combining these two forms of nitrofurantoin helps Macrobid stay in your body longer than Macrodantin.
Keep reading to learn more about the differences and similarities between Macrodantin and Macrobid.
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Understanding Antimicrobial Agents
Antimicrobial agents are substances used to prevent or treatinfections.
They can includeantiseptics,antibiotics,antifungals, andantivirals, among others.
Antimicrobials can kill microbes (germs) that cause illnesses or prevent them from growing and multiplying.
What They Treat
Antibiotics are a throw in of antimicrobial.
Antibiotics only treat conditions due to bacteria.
The first antibiotic used waspenicillin.
It was discovered in 1928 by Scottish scientist Alexander Fleming.
Penicillin is made from a mold calledPenicillium.Another commonly used antibiotic made from this mold isAmoxil (amoxicillin).
Although Macrodantin and Macrobid are antibiotics, they differ from penicillin and amoxicillin.
Nitrofurantoin, the active ingredient in Macrodantin and Macrobid, is not made from a mold.
Instead, it’s made by combining specific chemical molecules in a lab.
Treating UTIs
A UTI is an infection that occurs in any part of the urinary system.
UTIs occur when certain bacteria enter the urinary system.
Some ways this can happen include having sexual activity, usingspermicideor adiaphragmas abirth controlmethod, or using aurinary catheter.
The most common bacteria that may cause a UTI isE.
coli.Most UTIs are not severe and can be easily treated with a few days ofantibiotic treatment.
Notable Statistics
UTIs are not uncommon.
UTIs occur more frequently in females than males at birth.
What Is Macrodantin?
Macrodantin is an orally administered antibiotic approved by the FDA to treat UTIs resulting from certain bacteria, includingE.
This antibiotic does not work forUTIs that affect the kidneysand should not be used for this purpose.
Macrodantin is an oral capsule approved for adults and children 1 month and older.
The liquid form of nitrofurantoin is available under the brand name Furadantin.
Macrodantin and Furadantin are also available under the generic name nitrofurantoin.
This is called an off-label use.
Macrodantin is sometimes used off-label to help prevent UTIs.
In doing so, Macrodantin kills the bacteria and treats your infection.
What Is Macrobid?
Macrobid is an orally administered antibiotic similar to Macrodantin.
The FDA also approved it to treat UTIs triggered by certain bacteria, includingE.
Like Macrodantin, Macrobid should not be used to treat infections that affect the kidneys.
This drug is an oral capsule approved for use in adults and children 12 years and older.
It’s also available in a generic form called nitrofurantoin (monohydrate/macrocrystals).
Macrobid works similarly to Macrodantin, with one difference.
Macrobid is made up of nitrofurantoin monohydrate and nitrofurantoin macrocrystals.
Dosing Guidelines
The table below describes dosing recommendations for adults taking Macrodantin, Macrobid, or Furadantin.
Remember that these are dosages recommended by the manufacturers of these drugs.
If your healthcare provider prescribes any of these drugs, take the medication exactly as prescribed.
Dosing for Children
The following provides basic dosing guidelines for using Macrobid vs. Macrodantin in children.
Macrodantin
Macrodantin is approved for use in children ages 1 month and older.
Your child’s healthcare provider will calculate their Macrodantin dosage based on weight.
The recommended Macrodantin dosage for treating UTIs in children is 5 to 7/kg per 24 hours.
The total daily dose is divided into four doses given throughout the day.
To help prevent UTIs in children, the dosage is 1 mg/kg per 24 hours.
This dosage may be given in a single dose or two divided doses.
Which Drug Works More Quickly?
The effects of Macrodantin last about six hours.
With Macrobid, the drug is released in your body slowly over time.
Its effects last about 12 hours.
About 25% of Macrobid is released from your body in your urine.
Macrodantin and Macrobid’s most common side effects are mild and don’t require medical attention.
However, in rare cases, side effects may be more serious.
However, some rare side effects may last longer.
Be sure to follow their instructions carefully.
If you miss a dose of Macrodantin or Macrobid, take it as soon as you remember.
Then, take the next dose after your regularly scheduled number of hours have passed.
Do not take two doses together to make up for a missed dose.
This means the dose should be spaced out every six hours.
Macrobid doses are typically taken twice daily, spaced out every 12 hours.
This treatment typically lasts for seven days.
Taking Macrodantin Long-Term
Sometimes, healthcare providers may prescribe Macrodantin long-term to help prevent UTIs.
Typically, this dose is taken once per day at bedtime.
If you take Macrodantin long term, your healthcare provider will monitor you for signs of lung problems.
They’ll help you decide whether they’re safe during your pregnancy.
Potential for Interaction
Macrodantin and Macrobid may interact with some medications.
Avoid takingantacidsthat contain the ingredient magnesium trisilicate with Macrodantin or Macrobid.
This ingredient may decrease your body’s absorption of Macrodantin and Macrobid.
This may increase your risk of side effects from Macrodantin and Macrobid.
Antibiotics typically work by killing bacteria or preventing them from growing.
Macrodantin and Macrobid are both FDA-approved to treat UTIs.
Both drugs have the same active ingredient: nitrofurantoin.
Because of this, Macrobid is only taken two times per day.
Macrodantin is typically taken four times per day.
As with any antibiotic, it’s important to take Macrodantin or Macrobid exactly as prescribed.
Do not stop taking the drug until you’ve taken all the doses prescribed.
Stopping your antibiotic treatment too soon may cause the infection to return.
If it comes back, it may be more difficult to treat.
Frequently Asked Questions
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