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Nitrofurantoin MR
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Nitrofurantoin MR 100mg modified-release capsules are a high-efficacy antibiotic treatment used to clear urinary tract infections (UTIs) and cystitis by targeting the bacteria in the bladder.
- Provides targeted relief from stinging, frequent urination and lower abdominal pain
- Modified-release (MR) formula allows for convenient dosing
- Effective against common bacteria, including E. coli
- Discreetly delivered to your home following a quick online consultation
More information
"Nitrofurantoin MR is the first-line clinical recommendation for treating uncomplicated urinary tract infections in the UK. It is specifically formulated to concentrate in the urine, making it exceptionally effective at eradicating the bacteria causing cystitis while minimising the impact on the rest of your body's healthy bacteria. Patients typically see a significant reduction in symptoms within 48 hours of starting the course."
— Rachael Clarke MRCPharm MFRPSI FRSPH (GPHC Number: 2061366)
You can buy Nitrofurantoin online safely from Mail my Meds by completing a short clinical consultation which is reviewed by a registered UK prescriber. Once your assessment is approved, your medication is dispensed and shipped directly from our registered pharmacy (GPHC Number: 9011560) in discreet packaging to ensure your privacy.
Pricing for Nitrofurantoin 100mg modified-release capsules depends on the length of the course prescribed by our clinical team. We aim to provide transparent, competitive pricing that includes the cost of your online consultation, the private prescription, and the medication itself.
Mail my Meds offers several delivery options to ensure you receive your treatment as quickly as possible, including next-day delivery. We understand that UTI symptoms are uncomfortable, so we prioritise rapid processing of all approved orders placed before our daily cut-off time.
Nitrofurantoin is an antibiotic specifically designed to treat infections of the urinary tract, such as acute cystitis or kidney infections (pyelonephritis). Unlike broad-spectrum antibiotics, nitrofurantoin is filtered rapidly from the blood into the urine, allowing it to reach high concentrations exactly where the infection is located in the bladder or kidneys.
The active ingredient is nitrofurantoin, a nitrofuran antibacterial agent. In the modified-release (MR) version, the ingredient is processed to release slowly over several hours, which helps maintain steady levels of the medication in your system and reduces the frequency of doses required compared to standard immediate-release tablets.
Most users report that Nitrofurantoin is highly effective at stopping the "burning" sensation of a UTI within the first 24 to 48 hours. While some patients mention mild side effects like nausea, these are often managed by taking the capsule with a meal or a glass of milk. Clinical data from NICE supports its use as a primary treatment due to low bacterial resistance rates in the UK.
You should always read the Patient Information Leaflet (PIL) included in your medication box before starting treatment. The PIL contains vital data on ingredients, storage, and detailed safety information. You can also access a digital version on the electronic Medicines Compendium (eMC) website.
Nitrofurantoin works by entering the bacterial cells and damaging their DNA, RNA, and vital proteins, which prevents the bacteria from growing and multiplying. Because it attacks multiple targets within the bacterial cell simultaneously, it is much harder for bacteria to develop resistance to nitrofurantoin compared to other antibiotics.
You must take Nitrofurantoin capsules exactly as directed by your prescriber, usually twice a day for a duration of 3 to 7 days. It is essential to swallow the capsules whole with food or milk, as this increases the absorption of the medicine and significantly reduces the chance of feeling sick or having an upset stomach.
The standard dosage for treating an uncomplicated urinary tract infection in adults is one 100mg modified-release capsule taken twice daily. For a simple UTI, a 3-day course is often sufficient for women, while a 7-day course may be required for more persistent infections or for men.
Most people take Nitrofurantoin without experiencing serious issues, but like all medications, it can cause side effects in some individuals. Common side effects include:
- Nausea or vomiting
- Loss of appetite
- Headaches
- Dark yellow or brownish urine (this is harmless and expected)
If you experience a severe skin rash, difficulty breathing, or yellowing of the eyes (jaundice), stop taking the medication and seek medical attention immediately.
Nitrofurantoin is not suitable for everyone, particularly individuals with significant kidney disease or those in the final stages of pregnancy (38 weeks onwards). You should inform your prescriber if you have G6PD deficiency, anaemia, or diabetes, as these conditions may require extra monitoring while taking antibiotics.
| Treatment | Standard Dose | Main Benefit | Typical Duration |
|---|---|---|---|
| Nitrofurantoin MR | 100mg Twice Daily | Low resistance, stays in urine | 3 - 7 Days |
| Trimethoprim | 200mg Twice Daily | Effective if bacteria are sensitive | 3 Days |
| Pivmecillinam | 400mg initially, then 200mg | Good for resistant strains | 3 Days |
Can you drink alcohol on Nitrofurantoin?
Yes, there is no known direct interaction between alcohol and nitrofurantoin. However, alcohol can dehydrate you and irritate the bladder, which may worsen your UTI symptoms, so it is usually best to stick to water until you feel better.
How long does Nitrofurantoin stay in your system?
Nitrofurantoin is processed quickly by the body and is usually cleared from your system within a few hours after your last dose. Because it is eliminated so fast, it is vital to take your doses at regular intervals to keep the medicine working against the bacteria.
Can I take Nitrofurantoin without food?
It is strongly recommended to take this medication with food or milk. Taking it on an empty stomach significantly increases the risk of nausea and may reduce how well the medicine is absorbed by your body.
How quickly does Nitrofurantoin work for a UTI?
Most patients start to feel relief from the pain and urgency of a UTI within 24 to 48 hours. Even if you feel better quickly, you must finish the entire course prescribed to ensure the infection is completely cleared.
Does Nitrofurantoin treat BV (Bacterial Vaginosis)?
No, Nitrofurantoin is specifically for urinary tract infections and is not effective against Bacterial Vaginosis (BV). BV requires different antibiotics, such as Metronidazole, which target the specific bacteria found in the vaginal flora.
The information provided on this page is for general informational purposes only and should not replace seeking advice from a medical professional. Always consult with a doctor or pharmacist for personalised medical advice regarding your health conditions or treatments.
At Mail my Meds, our content is regularly reviewed by our team of UK-registered medical experts and pharmacists to ensure all information is up-to-date, accurate, and reflects the latest clinical guidelines from the NHS and NICE.
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