Drug class · Urinary
Urinary antibacterials
Also known as: urinary tract antibiotics, UTI antibiotics
Antibiotics used for urinary tract infections. The NHS describes nitrofurantoin as a medicine to treat urinary tract infections such as cystitis, and trimethoprim is also an NHS-described antibiotic for urinary tract infections.
- Also called
- urinary tract antibiotics, UTI antibiotics
Mechanism of action
Nitrofurantoin reaches useful concentrations only in urine, so it is used for lower urinary tract infections such as cystitis and is unsuitable for upper infections of the kidneys.
Members of the class
Members with a page on this site are linked.
Conditions treated
Class effects
- Nausea, diarrhoea, loss of appetite, headaches and dark yellow or brown urine are common side effects of nitrofurantoin, and usually go away when it is stopped.
- Itching or a skin rash may occur with trimethoprim, and these effects are usually mild and short-lived, according to the NHS.
- Serious reactions to nitrofurantoin, such as swelling of the throat or tongue or difficulty breathing, are rare; the NHS lists these as symptoms of anaphylaxis, which needs a 999 call.
Cautions
- The NHS lists a past allergic reaction, a lung condition, severe kidney problems, diabetes, anaemia or vitamin B deficiency, and porphyria among the reasons nitrofurantoin may not be suitable.
- The NHS says nitrofurantoin can usually be taken in earlier pregnancy, but a doctor may not recommend it later because it can affect the baby's red blood cells.
- For trimethoprim, the NHS lists an allergic reaction, liver or kidney problems and blood disorders such as porphyria among the reasons it may not be suitable.
- The NHS says trimethoprim can lower folic acid levels and is not usually recommended in early pregnancy.
Class interactions
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Connected pages in detail
What each linked page on Anatomy Nexus covers, in a line, for Urinary antibacterials.
Conditions
- Urinary tract infection Bacterial infection of the bladder (cystitis) or, when it ascends, the kidney (pyelonephritis), usually by gut bacteria such as Escherichia coli.
Medications
- Nitrofurantoin Nitrofurantoin is an antibiotic that the NHS describes as a medicine for lower urinary tract infections such as cystitis.
- Trimethoprim Trimethoprim is an antibiotic used to treat and prevent urinary tract infections such as cystitis, and occasionally other infections.
Educational content. A drug class page describes what a family of medicines has in common. Individual medicines differ in dose, licensing and interactions; treatment choices belong to a prescriber.