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Buy MacroBID online.

MacroBID is a well-known antibiotic used to treat cystitis. It’s also the brand name for the generic drug Nitrofurantoin.

Answer a few questions about your health, and we’ll recommend the right treatments for you. Order MacroBID online and get it delivered from our pharmacy.

Starting from £29.00
Here’s what's included in the price:
Answer a few questions about your health so we can get to know you better.
Free 24h delivery
Your treatment delivered in secure packaging, the very next day.
We’ll check in with you regularly to see how your treatment is going.
This page was medically reviewed by Dr Daniel Atkinson, GP Clinical Lead on August 02, 2022. Next review due on August 01, 2024.

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Macrobid MRNitrofurantoin

  • 100mg
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6 Capsules £29.00
14 Capsules £35.00 Save £32.67

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Disclaimer: The information provided on this page is not a substitute for professional medical advice, diagnosis, or treatment. If you have any questions or concerns about your health, please talk to a doctor.

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What is MacroBID?

MacroBID is an antibiotic tablet that’s used to tackle cystitis. It contains the active ingredient nitrofurantoin, and it’s one of the preferred treatment options for urinary tract infections, along with Trimethoprim. Each tablet contains 75 mg nitrofurantoin monohydrate and 25 mg nitrofurantoin macrocrystals.

MacroBID isn’t used to treat infections outside the urinary tract or bladder.

How does MacroBID work?

The bacteria most commonly responsible for cystitis is called escherichia coli. It’s a naturally occurring bacteria in the human body. It’s also present in our urine, but an infection often occurs when it gains access to the bladder from an external source, and it then begins to multiply.

The two active ingredients in MacroBID, nitrofurantoin monohydrate and nitrofurantoin macrocrystals, stop the bacteria from multiplying and kill it, which clears up the infection.

Cystitis is responsible for nearly 95% of symptomatic urinary tract infections. It’s estimated that between 140 and 175 million urinary tract infections occur annually worldwide. Cystitis has a number of causes but it’s mostly triggered by a bacterial infection or when there’s an imbalance in the body’s microflora. Sometimes, cystitis is also drug-induced.

What doses of MacroBID are there?

For cystitis treatment, MacroBID is available in a 100 mg dose. You should take one capsule twice a day for seven days.

If you’re still experiencing symptoms of cystitis after completing your course of treatment, you should contact our clinician. This is because continuous use has been linked with the development of kidney stones. Our clinician can advise you on what the next steps are, or on alternative treatment options.

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How to take MacroBID

  • For acute or recurring cystitis, take 100mg twice a day for seven days.
  • Take MacroBID orally with food or during mealtime. This way, the bioavailability of the active ingredient, nitrofurantoin, is improved by up to 40%.
  • Take it at 12 hour intervals.
  • As it is an antibiotic, it’s best to take it at evenly spaced times or at the same time each day. This ensures the concentration is high enough to combat the bacteria.
  • Try not to take a lesser or larger dose than what our clinician prescribes. Stopping too early will lead to resistance. Also, bear in mind that the drug will no longer be effective if the infection returns.
  • If you don’t have any kidney problems, the normal 100 mg dose is suitable. It’s not suitable for children under 12.

How long does it take MacroBID to work?

If your body doesn’t resist the drug, MacroBID should successfully clear the infection within the treatment course. Usually, symptoms of the infection start to disappear within 24 hours.

Even if you feel better before your treatment course is complete, you should still finish it. There may still be bacteria that’s inactive (but still living) in the urinary tract. Failure to complete the course might cause the bacteria to become resistant to the medication. If you have a recurring infection, MacroBID may not be as effective as it was initially.

What should I do if I make a mistake when taking MacroBID?

If you miss a dose, you shouldn’t take a double dose to make up for the one you miss. Instead, take the next dose as normal and continue the full course as before. If you suspect you have overdosed on MacroBID, please seek immediate medical assistance.

Medically reviewed by
Dr Daniel Atkinson
GP Clinical Lead
on August 02, 2022.
Meet Daniel
This page was medically reviewed by Dr Daniel Atkinson, GP Clinical Lead on August 02, 2022. Next review due on August 01, 2024.

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How is MacroBID different from other treatments for cystitis?

You can treat bacterial infections using different antibiotic treatment courses. MacroBID treatment is convenient and less demanding. This is primarily because you only need to take it twice daily, usually twelve hours apart. For example, if you take the drug at 7 am, you don't have to take the next dose until 7 pm.

Other treatment options may require eight hour intervals rather than 12. Our clinicians can suggest the most suitable and effective treatment option for you having factored in your health background.

Is MacroBID similar to any other treatments?

MacroBID is the branded version of the generic drug Nitrofurantoin. They both contain the same active ingredient, nitrofurantoin, and so work in the same way in the body. The only differences between the two are the packaging they come in and the appearance of the tablets themselves. Nitrofurantoin, as the generic, is also slightly cheaper.

Who is MacroBID for?

MacroBID is used for treating bladder infections, commonly known as cystitis. The most common cause of cystitis is a bacterial infection. Sometimes, you can also develop cystitis from a noninfectious route, such as drugs, radiation, catheter use, and hypersensitivity to chemicals. It’s possible for cystitis to clear up by itself after a few days, or even after consuming a large amount of water.

But if your symptoms persist for longer, you may need to speak to a clinician so that they can review if you’ll need to take MacroBID.

MacroBID may not be a suitable treatment if you have severely impaired kidney function. This is because the drug is released from your body via your kidneys.

MacroBID is poorly absorbed with medication containing magnesium trisilicate, such as antacids. Other drugs that MacroBID can interact with include:

  • Probenecid and sulfinpyrazone(decreases renal excretion of MacroBID)

  • Carbonic anhydrase inhibitors (decreases MacroBID anti-bacterial activity)

  • Quinolone (Anti-bacterial antagonism)

Do I need a prescription for MacroBID?

Yes. MacroBID is a prescription only treatment, so our clinician will need to decide if it’s safe for you to use based on your health background. It may not be a suitable treatment for you if you’re prone to  particular side effects, or if you’re allergic to any of the ingredients in it.

Why should I buy MacroBID online with Treated?

We want to make healthcare easy for you. We can recommend the right treatments for you based on your medical background and you can choose which one you’d like from our options. You can also set your own delivery schedule, so we’ll send you your medication when you want it, and in the quantity of it you’d like each time. 

We’ll keep in touch with you to ensure that your medication is working the way that it should. And if you have any questions about your treatment, our clinicians are here to help. Just sign in to your account and send them a message.
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