Home » Treatment » Nitrofurantoin MR 100mg capsules (6)
Nitrofurantoin MR 100mg capsules (6)
from£19.99
Nitrofurantoin MR 100mg capsules are a modified-release antibiotic used to treat and prevent urinary tract infections (UTIs), especially cystitis. They work by targeting bacteria in the bladder, providing effective relief with minimal side effects when taken as prescribed.
Nitrofurantoin MR 100mg capsules are an antibiotic medicine used to treat and prevent urinary tract infections (UTIs), especially cystitis [1]. The brand name for this medicine is Macrobid.
Here’s what you need to know:
Each capsule contains 100mg of modified-release nitrofurantoin.
It’s effective against the bacteria that most commonly cause bladder infections.
Usually prescribed for a short, three-day course for women with cystitis.
Can also be used in men and for prevention in some instances, as advised by a GP.
Available on prescription only and not over the counter.
The capsules are easy to swallow and designed to release the medicine steadily. This means you get continuous antibacterial action, helping to clear your infection quickly and efficiently [2].
As with all antibiotics, it’s crucial to take Nitrofurantoin exactly as prescribed. Don’t skip doses, and don’t stop taking the medication early, even if you feel better. This helps prevent resistance and ensures the infection is treated correctly [3].
For recurrent infections, your GP might recommend a longer course or preventative treatment, but this isn’t usually offered online.
Additional information
Pack size
1 x 6 capsules
MOJO WISDOM
Take control of your health by understanding your condition and what this medication is doing for you.
READ:
More information about this treatment.
UK-based doctors and pharmacists
Discreet and Confidential
UK-based doctors and pharmacists
Free, Expert Advice
No video link provided.
No video link provided.
UK-based doctors and pharmacists
Free, expert advice
Discrete and confidential
Fast delivery
Giving you trusted clinical advice for over 30 conditions
A UK regulated pharmacy providing safe, effective treatments online since 2014
Nitrofurantoin MR 100mg capsules are a first-line treatment for urinary tract infections (UTIs), especially cystitis, in adults.
They work by attacking the bacteria that cause UTIs, helping you feel better fast.
The medicine is highly concentrated in urine, making it super effective for bladder infections.
Most people start to feel relief within 2 to 3 days of starting treatment.
Always follow your healthcare provider’s instructions for safe and effective use.
Nitrofurantoin MR 100mg capsules are a go-to option for treating bladder infections, commonly known as cystitis, in adults. They are designed to deliver the active ingredient, nitrofurantoin, directly to the site of infection for maximum impact. The brand name for this medicine is Macrobid.
This antibiotic is well-established in NHS and NICE guidelines as a first-choice treatment for uncomplicated UTIs in women and is also used in men with certain clinical considerations [1][2].
The capsules are modified-release, meaning the medicine is released slowly over time, maintaining steady and effective drug levels in your system.
Unlike some antibiotics that can cause stomach upset or widespread side effects, Nitrofurantoin is filtered into the urine, allowing it to target the infection precisely where it’s needed. That means fewer side effects for most people and a faster return to everyday life [3].
It’s essential to take the full course, even if you start feeling better after a couple of days. Stopping early can allow the infection to return or make the bacteria resistant, which is a headache no one needs [1].
Active ingredient in nitrofurantoin 100 MR capsules
The active ingredient in Nitrofurantoin MR 100mg capsules is nitrofurantoin itself, an antibiotic specifically effective against many of the bacteria responsible for urinary tract infections. Nitrofurantoin works by interfering with bacterial enzymes and DNA, ultimately leading to bacterial cell death and clearance of the infection [3].
This antibiotic is unique in its ability to concentrate in the urine, making it particularly suited for treating bladder infections while minimising systemic exposure and reducing the risk of widespread side effects [1].
What are nitrofurantoin 100mg MR capsules used for?
Nitrofurantoin MR 100mg capsules are primarily used to treat uncomplicated urinary tract infections, particularly cystitis, an infection of the bladder. Cystitis symptoms can include pain or burning when urinating, frequent urges to urinate, and lower abdominal discomfort [1].
The capsules can also be used to prevent recurrent urinary tract infections in patients who experience frequent episodes. However, preventive treatment is usually managed by a GP and is not typically prescribed online [2].
In some cases, Nitrofurantoin may be prescribed to patients with more complicated infections or those at risk of kidney infections, but this is determined by a healthcare professional based on individual assessment [3].
How do nitofurantoin 100mg MR work?
Nitrofurantoin works by entering bacterial cells and disrupting essential processes. It damages bacterial DNA and enzymes, preventing the bacteria from multiplying and leading to their death. This targeted action helps clear the infection effectively [3].
Once ingested, the medication is rapidly absorbed and filtered by the kidneys, concentrating in the urine where the infection resides. This localisation means the drug acts directly on the bacteria in the bladder, reducing the chance of systemic side effects [1].
The modified-release formulation ensures a steady release of nitrofurantoin throughout the day, maintaining effective drug levels in the urine and enhancing treatment success [2].
How to use nitrofurantoin 100mg MR capsules?
Take Nitrofurantoin MR 100mg capsules exactly as prescribed by your healthcare provider. The capsules should be swallowed whole with a glass of water and taken with food or milk to improve absorption and reduce stomach upset [3].
Try to space your doses evenly, about 12 hours apart, such as one in the morning and one in the evening. This helps maintain steady drug levels in your system [2].
It’s important to complete the full course of treatment, even if your symptoms improve before finishing the capsules. Stopping early can lead to the infection returning or bacteria becoming resistant [1].
If you’re dealing with cystitis symptoms, there are a few simple self-care steps you can take to feel more comfortable while your treatment gets to work:
You can use over-the-counter pain relief like paracetamol or ibuprofen, as long as you don’t have any medical reasons to avoid them. These can help ease the discomfort while your body recovers. If you’re not sure which is best for you, have a quick chat with your pharmacist or GP for advice[1].
Try to drink plenty of fluids—aim for about 1.5 litres of water a day, unless you’ve been told to limit your fluid intake for another health reason. Staying hydrated helps your body flush out the infection more efficiently.
It’s best to skip over-the-counter cranberry products or urine alkalinising agents like potassium citrate, sodium citrate, or sodium bicarbonate. There’s no strong evidence that these help, so you’re better off sticking to the basics [4].
If you’re ever unsure about which remedies are safe for you, just ask your pharmacist—they’re always happy to help!
If your symptoms get worse quickly or become much more severe at any point, or if you don’t start feeling better within 48 hours of beginning your antibiotic treatment, it’s important to see a doctor straight away for a thorough check-up.
Warnings and precautions with nitrofurantoin 100mg MR capsules
Before taking Nitrofurantoin MR 100mg capsules, inform your healthcare provider if you have any allergies, kidney problems, or blood disorders such as anaemia or porphyria, as these conditions can increase the risk of side effects [3].
Nitrofurantoin is not recommended during the last trimester of pregnancy or during labour due to potential risks to the baby. Breastfeeding mothers should consult their doctor, especially if the baby has glucose-6-phosphate dehydrogenase (G6PD) deficiency [2].
Use caution if you have liver or lung disease, as Nitrofurantoin can sometimes cause complications in these organs. Report any breathing difficulties, cough, or jaundice to your doctor immediately [1].
Side effects of nitrofurantoin 100mg MR capsules
Common side effects of Nitrofurantoin include nausea, headache, and mild stomach upset. These usually resolve once the treatment course is completed [3].
Some people may notice their urine turns dark yellow or brown while taking Nitrofurantoin. This is normal and not harmful [1].
Serious side effects are rare but can include allergic reactions, lung inflammation, or liver problems. Seek immediate medical help if you experience symptoms such as difficulty breathing, rash, yellowing of the skin or eyes, or severe fatigue [2].
Potential side effects of nitrofurantoin
Blood and immune system – Rare blood disorders such as aplastic anaemia, low white cells (agranulocytosis, leukopenia), low platelets (thrombocytopenia), megaloblastic anaemia, and methaemoglobinaemia.
Digestive system – Nausea, diarrhoea, vomiting, stomach pain, and more serious but uncommon liver problems such as chronic active hepatitis, liver failure, autoimmune hepatitis, and (rarely) cholestatic jaundice.
Lungs and breathing – Pulmonary fibrosis, lupus-like reactions affecting the lungs, and a range of lung issues including acute, subacute, or chronic reactions, cough, and breathlessness.
Nervous system – Raised pressure inside the skull (benign intracranial hypertension), nerve damage (peripheral neuropathy), involuntary eye movements (nystagmus), dizziness, vertigo, headache, and drowsiness.
Skin and allergic reactions – Drug rash with systemic symptoms (DRESS), lupus-like skin reactions linked to lung involvement, severe skin reactions such as exfoliative dermatitis and erythema multiforme (including Stevens-Johnson syndrome); other rashes may appear as red, raised, or eczema-like, with possible cutaneous vasculitis, hives, itching, and temporary hair loss.
Joints and muscles – Joint pain (arthralgia).
Drug interactions with nitrofurantoin 100mg MR capsules
Nitrofurantoin can interact with certain medications, including antacids containing magnesium trisilicate, which can reduce its effectiveness. Inform your healthcare provider about all medicines you are taking to avoid interactions [3].
Other interactions may occur with drugs that alter urine pH or affect kidney function. Your doctor will review your medications to ensure Nitrofurantoin is safe for you [2].
Possible drug interactions with nitrofurantoin
Alkalinising agents (e.g. potassium citrate, sodium bicarbonate): May reduce the effectiveness of nitrofurantoin, though evidence is limited. Watch for signs of reduced efficacy.
Magnesium trisilicate: May lower absorption of nitrofurantoin. Monitor the treatment response.
Quinolone antibiotics (e.g. ciprofloxacin): Laboratory studies show they can counteract nitrofurantoin, but the real-world significance is unclear.
Drugs increasing neuropathy risk (e.g. amiodarone, isoniazid, lamivudine, metronidazole, phenytoin, stavudine): May raise the likelihood of peripheral neuropathy when taken with nitrofurantoin.
Live cholera vaccine: Effectiveness of the vaccine may be reduced. Avoid using nitrofurantoin from 14 days before until 10 days after vaccination.
Live typhoid vaccine: May lead to a weaker immune response. Stop nitrofurantoin and other antibacterials 3 days before vaccination and for 3 days after.
FAQs
What is nitrofurantoin 100mg used for?
Nitrofurantoin 100mg is used to treat bladder infections such as cystitis and can also help prevent recurrent infections in some cases [1].
How long does nitrofurantoin 100mg take to work?
You should start feeling better within 2 to 3 days after starting nitrofurantoin treatment [3].
What is the best time of day to take nitrofurantoin?
Take nitrofurantoin twice daily with food, ideally spaced about 12 hours apart, such as morning and evening [2].
Does nitrofurantoin make you tired?
Tiredness is not a common side effect of nitrofurantoin, but your infection or other side effects may cause fatigue [1].
Can I drink alcohol on nitrofurantoin?
Alcohol does not interact directly with nitrofurantoin, but it27s best to avoid it while treating an infection as it may worsen symptoms [3].
To provide the best experiences, we use technologies like cookies to store and/or access device information. Consenting to these technologies will allow us to process data such as browsing behavior or unique IDs on this site. Not consenting or withdrawing consent, may adversely affect certain features and functions.
Functional
Always active
The technical storage or access is strictly necessary for the legitimate purpose of enabling the use of a specific service explicitly requested by the subscriber or user, or for the sole purpose of carrying out the transmission of a communication over an electronic communications network.
Preferences
The technical storage or access is necessary for the legitimate purpose of storing preferences that are not requested by the subscriber or user.
Statistics
The technical storage or access that is used exclusively for statistical purposes.The technical storage or access that is used exclusively for anonymous statistical purposes. Without a subpoena, voluntary compliance on the part of your Internet Service Provider, or additional records from a third party, information stored or retrieved for this purpose alone cannot usually be used to identify you.
Marketing
The technical storage or access is required to create user profiles to send advertising, or to track the user on a website or across several websites for similar marketing purposes.
