Nitrofurantoin (MacroBID) for cystitis treatment

photo of Macrobid medicine packNitrofurantoin (MacroBID) is now available to women to buy online from Dr Fox in advance, ready for when needed. Nitrofurantoin is an antibiotic commonly used to treat uncomplicated cystitis.
How to order online

In the past few years nitrofurantoin has replaced trimethoprim as the first line treatment for cystitis.

Approximately 30% of cystitis infections in the UK are currently (2017) resistant to trimethoprim, compared with 3% resistance to nitrofurantoin.

Trimethoprim remains widely prescribed for cystitis and is still effective for many women. Similarly many women prefer nitrofurantoin. Choosing between the two is discussed in the medical information which forms part of Dr Fox’s online consultation for cystitis.


MacroBID 100mg is the only UK preparation of 100mg nitrofurantoin that is ‘modified/prolonged release’ and is taken twice daily (every 12 hours). There are other 100mg tablets of nitrofurantoin but they last 6 hours and are taken four times daily. ‘BID’ is a medical abbreviation meaning ‘take twice daily’.

A course of cystitis treatment is one capsule twice daily for three days, a total of six capsules. Macrobid comes in packs of 14 capsules, so Dr Fox pharmacy will split packs when supplying. Always read the patient leaflet. Be aware the manufacturer’s leaflet states a usual length of treatment for a bladder infection is 7 days but national medical guidelines advise a 3 day course is sufficient for uncomplicated infections which is now standard practice.


Cystitis treatment Quantity Cost
Nitrofurantoin 100mg 6 capsules (1 course) £10.90
Trimethoprim 200mg 6 tablets (1 course) £8.90

Further information