Nitrofurantoin is a medication that is sold under a few different brand names, including Macrobid. It’s an antibiotic which can be used to treat bladder infections, like cystitis.
For treating a bladder infection, the usual course of nitrofurantoin tablets lasts for three days. You need to take one tablet in the morning and one in the evening. Nitrofurantoin works by killing the bacteria which cause bladder infections.
Because of increased antibiotic resistance, nitrofurantoin is now the only recommended first-line antibiotic for treating cystitis in the UK.
To order cystitis treatment online, fill in our brief questionnaire. A Zava doctor will review your order and approve appropriate treatment.
Aratoin, MacroBid, MicroDantin, FuraDantin, and generic nitrofurantoin tablets all contain the active ingredient: nitrofurantoin.
The other ingredients in the MacroBid tablets offered by Zava:
- Maize starch
- Lactose monohydrate
- Sodium lauryl sulphate
- Quinoline yellow (E104)
- Titanium dioxide (E171)
- Black iron oxide (E172)
Like all medications, you may get side effects while taking nitrofurantoin. Common ones to look out for are:
- feeling sick (nausea) or being sick (vomiting)
- loose stools or diarrhoea
- loss of appetite
- stomach ache
- a skin rash
- a dark yellow or brown urine
Nitrofurantoin comes in capsules that are taken orally (by mouth). They are a type of antibiotic which is used to help your body recover from an infection by killing bacteria or stopping them growing.
Nitrofurantoin is most commonly used to treat cystitis, also known as urinary tract infections (UTI) or a bladder infection.
A lower dosage of nitrofurantoin can also be used to prevent cystitis from happening. It’s normally used in this way in people who get more than three episodes, or outbreaks, of cystitis in a year. At Zava we only offer nitrofurantoin to treat current cystitis infections and not for preventing future infections.
Nitrofurantoin is also used to prevent infections in people who are having surgery on their bladder or reproductive system.
Always take nitrofurantoin exactly as you’ve been told by a doctor or pharmacist. If you’re not sure, read the information leaflet that comes with the medication.
The dosage of nitrofurantoin that you take depends on what condition you have. The dosage that you’re taking is always written on the outside of the box of nitrofurantoin. The dosage to treat cystitis is one 100mg capsule twice a day for 3 days.
To take nitrofurantoin, you should swallow a capsule whole with a glass of water or milk. Don’t chew or open the capsule.
If you forget a dose, just take the dose as soon as you remember, unless it’s nearly time for your next dose. If it’s nearly time for your next dose, just skip the dose you forgot. Don’t take more than one dose to make up for a forgotten one.
If you find it difficult to remember all of your doses of nitrofurantoin, you could set alarms on your phone to remind you. Or, you can pair taking nitrofurantoin with a task that you do every day. For example, you can take nitrofurantoin after you brush your teeth.
Accidentally taking more nitrofurantoin than you should is unlikely to cause you harm. But, speak to a doctor or pharmacist if you:
- took more than one extra dose
- are getting severe side effects
- are otherwise worried
If you speak to a doctor or pharmacist in person, make sure you take the packet of nitrofurantoin with you and let them know how much nitrofurantoin you’ve taken and the time that you took it.
Nitrofurantoin helps the body fight off cystitis by killing the bacteria that are responsible for the infection.
After you take nitrofurantoin, your body starts to process the medication by absorbing it into your blood. It then gets filtered by the kidneys into the bladder, putting the medication close to the bacteria that cause cystitis.
Once it’s in the bladder, nitrofurantoin gets inside the bacterial cells and damages their genes (DNA). This kills the bacteria and helps the body get rid of the infection.
Treatment with nitrofurantoin is suitable for you if you:
- have cystitis and you’re a woman, not pregnant, and don’t currently have a small tube inserted to remove urine from the body (catheter)
- have had more than three episodes of cystitis in a year and would like to take nitrofurantoin to prevent another episode from happening. This service is not offered at Zava
- are going to have surgery to your bladder or your reproductive system. This service is also not offered at Zava
You shouldn’t take nitrofurantoin if you:
- have a blood disorder called acute porphyria
- have a genetic disorder called G6PD deficiency
Speak to a doctor before taking nitrofurantoin if you:
- have been told you have anaemia
- have diabetes
- have a deficiency of folate
- have pulmonary disease
- are at risk of getting peripheral neuropathy
Nitrofurantoin is a safe and effective medication to use during most of the time you’re pregnant.
Taking nitrofurantoin when you’re pregnant doesn’t put your baby at a higher risk of negative consequences, like birth defects, stillbirth, low birth weight, or premature birth.
Taking nitrofurantoin when you’re between 38 and 42 weeks pregnant could put your baby at risk of jaundice (yellowing of the skin and eyes). This condition can get better on its own after a few weeks, or it can be treated by light therapy if it’s more severe. So, it can be good to avoid nitrofurantoin if you’re at this stage of pregnancy.
Nitrofurantoin can interact with other medicines. Speak to your doctor before taking nitrofurantoin if you’re also taking:
- Dapsone: this medication is used to treat a certain skin condition called dermatitis herpetiformis
- Prilocaine: this medication is used as a local anaesthetic and to treat long-term pins and needles (parasthesia)
Nitrofurantoin doesn’t react with alcohol. But, we don’t recommend drinking too much alcohol if you have cystitis, because alcohol may make your symptoms worse.
Like with all medications, nitrofurantoin might cause some side effects. There are some things that you can do to help you cope with side effects if you get them:
- Eat light, plain meals if you’re having an upset stomach with nitrofurantoin
- Don’t drive if you find that you get drowsy or dizzy after taking nitrofurantoin
Allergic reactions are a rare but serious side effect of taking nitrofurantoin. Go to your nearest Accident and Emergency department straight away if you get any of these symptoms:
- Swelling of the face, lips, and tongue
- A raised, itchy rash over your whole body (hives)
- Wheezing or difficulty breathing
Dr Nicholas Antonakopoulos graduated from the University of London in 2006. He did his postgraduate training in hospitals in the London area, and he trained for four years in Trauma and Orthopaedic Surgery before completing his training in General practice in 2015.Meet our doctors
Last reviewed: 24 Mar 2019
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