Nitrofurantoin Monohydrate/Macrocrystals

Nitrofurantoin Monohydrate Macrocrystals Nitrofurantoin Monohydrate / Macrocrystals is a generic version of an antibiotic used to treat bladder infections (also known as UTIs) by stopping the growth of the bacteria that causes the infection. The medication comes in the form of capsules. Read more about urinary tract infection.
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Using this information

This overview does not include all the information available about this medication. It doesn't guarantee your personal safety while using it. And it doesn't guarantee that the medication will be effective or suitable for you. You should not trust it over advice from a medical professional.

Contact your health provider for accurate information about this medication and your treatment. You can update your UTI treatment online by requesting a provider callback via your patient dashboard.

Medication name
Key points about Nitrofurantoin

Nitrofurantoin treats urinary tract infections (UTIs) and prevents UTIs. An antibiotic, this UTI medication works by stopping bacterial growth. It does not treat viral infections like the common cold or flu.

The unnecessary or excessive use of any antibiotic can reduce Nitrofurantoin’s effectiveness. Children under 1 month should not use Nitrofurantoin as they're at risk for hemolytic anemia. (It’s a condition where red blood cells are destroyed faster than replenished.)

Administration of Nitrofurantoin
  • Take this UTI antibiotic by mouth. It’s usually taken with food or milk. But follow the directions of your healthcare provider.
  • To treat a UTI infection, this medication is typically taken twice daily, every 12 hours. To prevent an infection, it's usually taken once at night.
  • Your medical condition and response to UTI treatment determine how much medication you'll take and how long you'll take it. For children, dosage is also determined by body weight.
  • Swallow the pill for UTI whole. Do not crush, cut or modify the tablet.
  • To achieve the best results, take this medication at the same time(s) every day.
  • Try not to take antacids containing magnesium trisilicate while on this UTI medicine. They can interfere with the medication's absorption and effectiveness.
  • Strictly follow your UTI prescription regimen. Only skip a UTI pill dose or stop this medication with medical provider approval.
  • If you recognize symptoms of a new UTI, contact your provider immediately. Common UTI symptoms include burning while peeing, bloody urine or dark or cloudy urine. You can request a callback at your Dr. B patient dashboard.
  • Continue taking this UTI treatment medication until you complete the prescribed amount. (Finish it even if symptoms go away sooner.) Bacteria may continue to grow if you stop taking the UTI medication too soon. This can then lead to a relapse infection. 
  • If symptoms persist or worsen, request a callback from your healthcare provider via your patient dashboard.
Possible side effects
  • You may experience nausea, vomiting, loss of appetite or headaches. To avoid nausea, try taking this UTI medicine with food. If these persist or worsen, request a callback from your medical provider through your patient dashboard.
  • Nitrofurantoin may cause dark urine or urine with a dark yellow or brown hue. This side effect is harmless and will stop after you finish the medication.
  • A medical professional prescribed this UTI medication because its benefits outweigh potential side effects. The majority of people who use this UTI medicine do not suffer from serious adverse reactions.
  • In rare cases, Nitrofurantoin may induce serious (and potentially fatal) lung complications. Such issues may arise within the initial month of treatment. Or they may follow prolonged usage (generally exceeding six months). Watch for a persistent cough, chest pain, shortness of breath, difficulty breathing, joint or muscle pain or bluish/purplish skin. If you experience any of these, seek immediate medical help.
  • If you experience serious side effects, contact your healthcare provider immediately. These include severe or persistent headaches, easy bruising or bleeding and changes in mental/mood or vision. They may also include new signs of infection like a persistent sore throat or fever.
  • In rare instances, this medication may lead to an intestinal condition caused by an overgrowth of the C. difficile bacteria. This can occur during treatment or several weeks to months after stopping treatment. Symptoms include persistent diarrhea, abdominal or stomach pain/cramping and blood or mucus in your stool. If you experience any of these, request a callback from your healthcare provider. Avoid using anti-diarrhea medicines or opioids as they may exacerbate symptoms.
  • Continued or regular use of this medicine can cause oral thrush or vaginal yeast infections. Look out for white spots in your mouth, a difference in your typical vaginal secretions or other changes. If you experience any of these, request a callback from your medical provider.
  • This isn’t a complete list of possible side effects. If you notice side effects not listed above, you can update your UTI treatment online. Just request a medical provider callback through your patient dashboard.
Important precautions to consider
  • Before starting Nitrofurantoin treatment, inform your provider about any known allergies. These include allergies to this medication, other medications or other substances. This product might contain inactive ingredients that could trigger an allergic reaction or other complications.
  • Give your provider a comprehensive medical history before starting UTI antibiotics. This is vital if you have a family history of kidney disease, liver disease (including past liver issues caused by Nitrofurantoin), G6PD deficiency, anemia, lung diseases, peripheral neuropathy, optic neuritis, diabetes, untreated mineral imbalance or vitamin B deficiency.
  • Nitrofurantoin may make live bacterial vaccines (like the typhoid vaccine) less effective. Let your provider know you're taking Nitrofurantoin before any immunization or vaccination.
  • Kidney function tends to decline with age. So it's important to note that the kidneys process Nitrofurantoin from the body. Because of this, older adults may have a higher risk of side effects like nerve, liver or lung problems. Refer to the "Possible side effects" section for more details.
  • Only use Nitrofurantoin during pregnancy if absolutely necessary. Do not use it close to or during delivery—38 to 42 weeks of pregnancy. Potential harm to newborns includes hemolytic anemia—a blood disorder where blood cells are not replaced as fast as they're destroyed.
  • If you're breastfeeding, consult your OB/GYN before using this medication. Nitrofurantoin can pass through breast milk. So it may cause an unwanted effect on nursing infants under one month old. It can also adversely affect those with G6PD deficiency—a specific genetic condition.
Drug interactions
  • Drug interactions can alter the efficacy of your medication or increase the risk of severe side effects. Please note that this document does not encompass all possible drug interactions.
  • To ensure safety, maintain a comprehensive list of all products you use and share it with your healthcare provider. These include prescription/nonprescription drugs and herbal products.
  • Only initiate, discontinue or modify the medication dosage with direct approval from your healthcare provider.
  • Sulfinpyrazone may interact with this UTI medication. This can influence the outcome of cupric sulfate-type urine glucose tests. Before taking a urine glucose test, tell laboratory personnel and related medical providers you're taking Nitrofurantoin.
What to do in the event of an overdose

In the event of an overdose with symptoms like loss of consciousness or difficulty breathing, immediately call 911. For less severe symptoms, contact your local poison control center at 1-800-222-1222.

Additional points to consider

Your provider prescribed this UTI medication for your specific, current condition. Do not share this medication with others. Don't use it for a following infection unless instructed by a healthcare provider.

To track your progress and identify potential side effects, stay up-to-date with periodic laboratory and/or medical tests. These include complete blood counts, kidney and liver function assessments and urine cultures. Request a callback from your healthcare provider for further details.

What to do if you missed a dose

Forget to take a dose? Take it as soon as you’ve remembered. But if it’s close to the time for your next scheduled dose, don’t try to catch up. Just skip the missed dose and continue with your regular dosing schedule.

Proper storage of this medication
  • Store Nitrofurantoin at room temperature, away from direct light and moisture.
  • Refrain from storing it in the bathroom. (It’s steamy there.)
  • Make sure children and pets can't reach or get into any medication.
  • If you no longer need the medication or it expired, contact your pharmacist or local waste disposal company. They'll tell you how to best dispose of it. Only flush medications down the toilet or drain if instructed to do so.
Generic Name
Nitrofurantoin Monohydrate Macrocrystals
Nitrofurantoin Monohydrate Macrocrystals
Drug Class
Nitrofuran antibiotic

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