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Nitrofurantoin MR
In Stock
Friday, 03 Jul 2026
Medication features
Nitrofurantoin for UTI Relief
Nitrofurantoin MR 100mg (Macrobid) is an antibiotic used to treat urinary tract infections (UTIs) in women, caused by bacterial infections in the urinary tract. It works to clear the infection and relieve symptoms such as pain, burning, and discomfort.
- Treats UTIs and bacterial infections
- Modified-release formula
- Take one capsule (100mg) twice daily
- Each capsule contains 100mg of nitrofurantoin
Overview
NOTE: After selecting this product, you will need to complete a short assessment, so we can make sure this medication is suitable for you.
Nitrofurantoin for UTI treatment
Nitrofurantoin is an antibiotic that is designed to combat bacterial infections of the urinary tract, offering quick relief from burning sensations, discomfort, and frequent urges to urinate.
When a urinary tract infection strikes, you need a treatment that works fast and effectively as UTIs are painful and uncomfortable. Whether you are dealing with an occasional infection or recurrent cystitis, Nitrofurantoin offers targeted action to help you feel better, sooner.
What is Cystitis?
Cystitis is a common urinary tract infection that causes inflammation of the bladder. It is caused by bacteria, especially E.coli, entering the urethra and infecting the lower urinary tract (the bladder and urethra). It leads to symptoms such as cloudy or strong-smelling, burning sensation while urinating, and needing to go to the toilet more often.
Cystitis is more common in women than in men but can affect anyone, including children and older adults. Mild cases may clear up on their own but persistent or severe symptoms may require antibiotics such as Nitrofurantoin. More about Cystitis.
What is Nitrofurantoin?
Nitrofurantoin is a prescription medication for the treatment and prevention of urinary tract infections (UTIs), including cystitis. Unlike broad-spectrum antibiotics, Nitrofurantoin eliminates bacteria in the bladder and urinary tract without disrupting the body’s natural balance.
It is suitable for: Men, women, children, and older adults
Nitrofurantoin is available in the form of:
- Oral capsule
- Oral suspension
What is Nitrofurantoin used for?
Nitrofurantoin 100 mg and 50 mg tablets are used to:
- Relief symptoms of UTIs such as cystitis, urethritis, prostatitis, and epididymitis
- Prevent recurrent infections
This medicine does not work for flu, cold, or other viral infections.
Is Nitrofurantoin effective antibiotic for cystitis?
This medication is widely used in the UK to treat uncomplicated urinary tract infections.
According to the clinical trial, the cure rate is 61% for a 3-day course of Nitrofurantoin. Although Nitrofurantoin is one of the effective antibiotics for cystitis, further investigation on this medicine is needed to ensure maximum efficacy.
How does Nitrofurantoin treat cystitis (UTI)?
Nitrofurantoin targets bacteria in the bladder and urinary system, interfering with bacterial DNA, preventing their growth, and ultimately killing them.
Unlike other antibiotics for urinary tract infections, Nitrofurantoin concentrates in the urine in the form of microcrystals, making it highly effective for UTIs while lowering its impact on the rest of your body.
Always follow your doctor’s advice regarding Nitrofurantoin cystitis treatment and complete the full course to avoid resistance.
How long does it take to work?
Nitrofurantoin starts working within a few hours of taking the first dose but symptoms begin to improve within 3-5 days. You must take this medicine for 3-7 days even if you start feeling better to ensure the infection is fully cleared. If your symptoms do not improve after a couple of days or get worse, consult your healthcare professional.
Besides this, if you are taking this medicine to prevent UTIs from coming back, you must take it for several months, even if you do not have symptoms. If you want to prevent an infection after having surgery, take this medicine on the day of the operation and for the next 3 days.
How to Take Nitrofurantoin for Cystitis
- Dosage: Take one 100 mg capsule twice daily (every 12 hours) for 3 days.
- With food or milk: Helps absorption and reduces stomach upset.
- Results: Symptoms should start improving within 24 hours and resolve in 3 days.
Important note: Your urine may turn dark yellow or brown—this is normal. If symptoms don’t improve or worsen, see a doctor.
Alternatives to Nitrofurantoin for UTI
If Nitrofurantoin does not suit you, you can opt for other options such as:
- Trimethoprim
Nitrofurantoin vs. Trimethoprim
Nitrofurantoin and Trimethoprim are used to treat UTIs such as cystitis; they differ in many ways such as:
Nitrofurantoin is effective against common UTI-causing bacteria and is less likely to cause antibiotic resistance. On the other hand, Trimethoprim is less effective in certain cases and resistance rates are also higher.
Nitrofurantoin interferes with bacterial DNA, preventing their growth, and ultimately killing them. On the other hand, Trimethoprim inhibits dihydrofolate reductase, preventing folic acid synthesis and ultimately killing them.
Nitrofurantoin is prescribed as 50mg and 100mg tablets while Trimethoprim is prescribed as 100mg or 200mg tablets.
Nitrofurantoin is only used to treat UTIs caused by susceptible bacteria, whereas Trimethoprim is used to treat UTIs, ear infections, and kidney infections caused by specific bacteria.
Clinical trials have shown that both were well tolerable in women and effective for the treatment of UTIs.
However, the selection between these medications depends on the patient's health conditions, bacterial resistance, and doctor’s recommendations.
Resources
Nitrofurantoin, NCBI.
MACRODANTIN- nitrofurantoin macrocrystals capsule, Dailymed.
Nitrofurantoin: properties and potential in treatment of urinary tract infection: a narrative review, PMC.
Nitrofurantoin: a reminder of the risks of pulmonary and hepatic adverse drug reactions, GOV.UK.
MACROBID - nitrofurantoin monohydrate and nitrofurantoin, macrocrystalline capsule Procter and Gamble Pharmaceuticals, Inc, FDA.
Directions
Dosage
100mg of Nitrofurantoin, twice a day, for 3-7 days.
For more information, see the patient leaflet: https://www.medicines.org.uk/emc/files/pil.428.pdf
Missed dose
If you forget to take a Nitrofurantoin dose, take it as soon as possible. If it is almost time for your next dose, skip the missed dose and take your next dose on a regular dosing schedule. Do not take double or extra doses to make up for the missed one.
Overdose
If you take too much Nitrofurantoin, you may experience severe nausea or vomiting. In this case, seek emergency help or contact the Poison Control Center right away.
Warnings
Nitrofurantoin warnings
Who Should not Take Nitrofurantoin?
You should not take Nitrofurantoin tablets if you have:
- History of kidney disease
- Liver disease
- Lung disease
- Anemia
- Vitamin B deficiency
- Diabetes
- Mineral imbalance in the blood or
- Glucose-6-phosphate dehydrogenase (G6PD) deficiency (a rare condition that affects red blood cells)
- Trouble urinating
- Allergic reaction to Nitrofurantoin or any other ingredients present in this medicine.
For more information, see the Nitrofurantoin patient information leaflet: https://www.medicines.org.uk/emc/files/pil.428.pdf
Interaction with other medicines: What not to mix with Nitrofurantoin?
Many prescription and over-the-counter medications, herbal products, vitamins, minerals, and supplements can interact with Nitrofurantoin, lowering its effectiveness and leading to adverse reactions. These may include:
- BCG vaccine live
- Darolutamide
- Cholera vaccine
- Lasmiditan
- Pretomanid
- Pexidartinib
- Typhoid vaccine live
- Selinexor
- Azathioprine
- Fluconazole
- Mercaptopurine
- Levoketoconazole
- Methotrexate
- Antacids containing magnesium trisilicate
- Quinolone antibiotics such as ciprofloxacin, norfloxacin, lomefloxacin, and ofloxacin
- Probenecid
- Sulfinpyrazone
Besides these, if you are taking or have taken any other medicine, tell your doctor before taking Nitrofurantoin to avoid serious complications.
Note: You can take paracetamol or ibuprofen with Nitrofurantoin to ease the discomfort of your symptoms.
For more information, see the Nitrofurantoin patient information leaflet
FAQ
Can you drink alcohol with this medicine?
You can drink alcohol while taking Nitrofurantoin as there are no direct harmful interactions between the two. However, you must consume it in moderation as drinking a lot of alcohol can delay your recovery from illness and worsen side effects such as dizziness, nausea, or drowsiness. Always follow your doctor’s advice, limit fizzy drinks, and consume alcohol in moderation to avoid adverse effects.
Can you buy Nitrofurantoin over the counter?
Nitrofurantoin is available on prescription only in the UK, meaning you cannot buy it over the counter. You will need a prescription from a doctor, GP, or online pharmacy to obtain this medication.
You can buy Nitrofurantoin MR 100mg (Macrobid) from a licensed online pharmacy after receiving a valid prescription.
Nitrofurantoin in pregnancy
You can take Nitrofurantoin for urinary tract infections including cystitis during pregnancy, especially in the first and second trimesters. However, you must avoid it in the third trimester or the last few weeks of pregnancy as it may affect your baby’s red blood cells. So, if you are pregnant and need treatment for a UTI, consult your doctor for a safe option.
Nitrofurantoin in Breastfeeding
Nitrofurantoin passes into breast milk in small amounts and is unlikely to cause side effects in your baby. So, it is safe to use it while breastfeeding.
However, it is not suitable for breastfeeding mothers of babies under 3 months old as it can increase the risk of a rare condition called hemolytic anemia in newborns. Consult your doctor to determine whether you can take it while breastfeeding or not.
Nitrofurantoin in Fertility
There is no strong evidence that this medicine affects fertility in men or women. So, if you are trying to conceive, you can take Nitrofurantoin antibiotics for bladder infection; however, you must consult your doctor for personalized advice.
Is Nitrofurantoin a very strong antibiotic?
Nitrofurantoin is a strong antibiotic as it works against a range of bacteria in the urinary tract such as Enterococcus faecalis, E. coli, & species of Klebsiella, Staphylococcus, and Enterobacter. It is less likely to cause antibiotic resistance compared to other antibiotics.
Can Nitrofurantoin make you feel weird?
Nitrofurantoin can make you feel weird due to its side effects such as drowsiness, dizziness, headaches, or nausea. Some feel lightheaded or discomfort, leading to mood changes or weird feelings.
Does vitamin D interact with Nitrofurantoin?
Vitamin D does not interact with Nitrofurantoin; however, it does not mean that interaction will never occur. Before taking vitamin D with Nitrofurantoin, consult your doctor to avoid adverse effects.
Can Nitrofurantoin be used for kidney infection?
Nitrofurantoin is not suitable for kidney infections (pyelonephritis) as it works in the bladder and does not reach high enough levels in the kidneys. For kidney infections, doctors may prescribe ciprofloxacin or co-amoxiclav that effectively targets deeper infections.
How long does Nitrofurantoin stay in your system?
Nitrofurantoin stays in your system for about 4-5 hours and after this, it is quickly exerted in your urine. This thing makes it more effective in treating urinary tract infections. Once you take it by mouth, most of the medicine gets filtered out of your blood and into your bladder and kidneys. In this way, this medicine directly targets the bacteria that is causing infection in the urinary tract, improving your symptoms within two days of starting treatment.
How to store Nitrofurantoin?
You must store Nitrofurantoin at a temperature between 68-77 degrees F (20-25 degrees C). moreover:
- You can also expose it to temperatures between 59 F-86 F (15 C-30 C) for shorter periods of time, such as when transporting it.
- Store it away from direct light, moisture, and heat.
- Do not store in the bathrooms.
- Do not freeze your medicine.
- Keep it away from the reach of children and pets.
- Dispose of outdated medicine or medicine no longer needed via the medicine take-back program to protect the environment, children, other people, and animals.
- Do not flush this medication down the toilet.
- If you still have concerns, consult your doctor for better advice.
Side Effects
Nitrofurantoin side effects
Like other medications, Nitrofurantoin tablets cause some side effects; however, not everyone gets them. The details of these side effects are:
Common side effects:
- Vomiting
- Mild diarrhoea
- Nausea
- Sleepiness
- Headaches
- Loss of appetite
- Dark yellow or brown pee
- Stomach pain
- Pain in your hands and feet
- Weakness
- Headache
- Dizziness
- Drowsiness
- Uncontrollable eye movements
These side effects do ot require medical attention and may resolve on their own within a few days. If they persist or get worse, speak to your doctor.
Serious side effects
It rarely causes serious side effects, in less than one in 1000 people. These may include:
- Jaundice: Its signs may include yellowing of the skin and eyes, dark urine, loss of appetite, nausea, and vomiting, indicating liver or gallbladder problems.
- Lung problems (especially if you take this medicine for longer than 6 months): Its signs may include coughing up blood, coughing up mucus, chest pain, tiredness, chills, fever, and shortness of breath.
- Allergic reactions: Its signs may include chest tightness, wheezing, trouble breathing, or swelling of your tongue, throat, or face.
- Nerve problems: Its signs are pins and needles, tingling and numbness, and muscle weakness.
- Hemolysis (red blood cell damage warning): Its signs are pale skin, weakness, and tiredness.
- Lupus-like syndrome: Its signs may include swollen glands, joint pain or swelling with fever, chest pain, muscle aches, unusual thoughts or behavior, vomiting, and patchy skin color.
- Severe headaches
- Unexplained bruising or bleeding
- Severe diarrhea, leading to dehydration
- Vaginal itching or discharge
If you get any of these side effects, consult your healthcare professional immediately.
Information
Nitrofurantoin patient information leaflet
Nitrofurantoin drug facts
- Nitrofurantoin brand name: Macrodantin, Macrobid, Furadantin
- Nitrofurantoin class: Antibiotics or urinary anti-infectives
- Generic name: Nitrofurantoin, Nitrofurantoin macrocrystalline
- Pronunciation: nye-troe-fyoor-AN-toyn
- Availability: Prescription only
- Usage: Liquid or capsule that is swallowed
Delivery
Once your order has been approved by our UK medical team it will be dispatched via Royal mail. All orders are sent using a tracked and signed for service.
Royal Mail 48 (2-5 days) | £2.49
Estimated delivery within 2-3 working days. Excludes bank holidays. Not a guaranteed service.
Free standard delivery on orders over £45.
Royal Mail 24 (1-2 days) | £2.95
Estimated delivery within 1 working day. Excludes bank holidays. Not a guaranteed service.
Royal Mail Special Delivery Guaranteed by 1pm | £6.99
Order by the 2:00 PM weekday cut-off time for guaranteed delivery by 1:00 PM the next business day.
Orders placed after the cut-off on Friday will be delivered on Tuesday.
Price Comparison
| Medication | Ashcroft Pharmacy |
|---|---|
| 100mg x6 capsule | £13.99
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Written and reviewed by our qualified team
Authored by:
Mr Suhail Jamil
Superintendent Pharmacist
GPhC Number: 2069518
Order Monday to Friday before 14:00pm to guarantee next day delivery
