Trimethoprim is an effective anti-biotic medication that can quickly and safely treat cystitis.



0.0 starred - 0 Reviews

What is Cystitis?

Cystitis, also known as a lower urinary tract infection, usually only affects your bladder. Your urinary tract consists of your kidneys, two ureters (the tubes that connect each kidney to your bladder), your bladder and your urethra. Sometimes the infection can go higher to your ureters or kidneys – this is known as an upper urinary tract infection and is a more serious illness.

Cystitis is usually caused by a bacterial infection from a variety of sources. It can also be triggered by irritation or bruising of your urinary tract caused by sexual intercourse. It's most common in women. Around one in three women will have at least one bout of cystitis before they are 24 years old. Doctors believe it is less common in men because they have longer urethras and bacteria have further to travel to reach the bladder.

Symptoms of Cystitis

Symptoms of cystitis usually develop over several hours or a day. Common symptoms include:

  • pain when you pass urine or straight afterwards – this is usually a burning or stinging sensation
  • a frequent, urgent need to urinate, but you only pass small amounts or no urine
  • cloudy, dark or strong smelling urine
  • blood in your urine – this may not always be visible, but can be seen under a microscope or by testing the urine
  • pain during sexual intercourse
  • pain in your lower abdomen (tummy) or lower back

Causes of cystitis

  • Cystitis is usually caused by a bacterial infection. A bacterium called Escherichia coli (E.coli), which usually lives harmlessly in your bowel, causes around eight out of 10 bouts of cystitis.
  • Bacteria can get into your urinary tract and cause infection in different ways. These can include the following:
  • Bacteria are more likely to get into your bladder when you have sex. Sexual intercourse can also bruise your urethra and bladder, which can cause similar symptoms to cystitis.
  • Poor hygiene is a common cause if you’re a woman, as women have shorter urethras than men – this means there is a shorter distance for the bacteria to travel to the bladder. The urethra is also closer to the back passage (anus) in women. This makes it easier for bacteria to get transferred from the anus into the urethra.
  • Bubble baths and fragranced products can irritate your urethra and bladder.
  • If you’re pregnant, extra pressure on your womb (uterus) might mean that your bladder doesn’t empty completely. This can encourage bacteria to grow.
  • If you have diabetes, your urine can contain more sugar than usual, which can encourage bacteria to grow.
  • Postmenopausal women have lower amounts of certain hormones. This can lower the normal defences of the urethra to allow bacteria to grow.
  • If you have a catheter for a long period of time, it’s likely that bacteria will grow and your bladder will become infected.
  • Kidney or bladder stones can prevent your bladder from emptying fully, which can encourage bacteria to grow.
  • Rarely, reoccurring cystitis can be caused by a tumour in your bladder.

Cystitis is less common among men. If you’re a man, cystitis generally starts with an infection in your urethra that moves into your prostate, then into your bladder. The most common cause of reoccurring cystitis in men is a bacterial infection of the prostate or passing urine less often because your prostate is enlarged.

Trimethoprim Anti-Biotics for Cystitis Treatment

Trimethoprim is an effective anti-biotic for treating and preventing certain types of bacterial infections including bacterial urinary tract infections (UTIs). A course of Trimethoprim twice daily for duration of 3 days (6 doses) is very effective at treating ystitis.

How to Take

One 200mg trimethoprim tablet, twice daily for 3 days. Swallow the tablets with a glass of water at the same time each day.

Side Effects of Trimethoprim

Like all medicines, Trimethoprim tablets can cause side effects, although not everybody gets them. Please tell your doctor or pharmacist if you notice any of the following effects or any effects not listed.

Contact your GP at once if you get an allergic reaction such as swelling of the face, lips, tongue or throat, difficulty breathing, shock or collapse. Aseptic meningitis can occur in some patients. This may show as a combination of symptoms such as headache, fever, stiff neck, tiredness, feeling ill and your eyes become very sensitive to bright light.

Tell your doctor if you notice any of the following side effects or notice any other effects not listed:

  • Blood: altered number and type of certain blood cells. If you get increased bruising, nose bleeds, sore throats or infections you should consult your doctor. Too much potassium in the blood (you may experience muscle cramps or pain, irregular heartbeats, unusual tiredness or weakness).
  • Stomach: feeling or being sick, sore mouth, discomfort, this is usually mild and disappears after stopping the tablets.
  • Skin: sensitivity to light, skin rashes which may be itchy, severe skin reactions such as exfoliative dermatitis (itchy, scaly, flaking, swollen skin), erythema multiforme (circular, irregular red patches), Stevens-Johnson syndrome (severe skin rash with flushing, fever, blisters or ulcers) or toxic epidermal necrolysis (severe rash involving reddening, peeling and swelling of the skin that resembles severe burns).
  • Liver: changes in liver enzymes (seen in tests), jaundice (yellowing of skin or whites of the eyes).
  • Kidney: increase in blood creatinine and urea levels (seen in tests).
  • Muscles: muscle pain.
  • Other: red, swollen tongue, headache.

If you notice any side effects, they get worse or if you notice any not listed, tell your GP or pharmacist.

Patient Information Leaflet

Always read the patient information leaflet before commencing treatment. Patient information can be found here.


Alternative Anti-Biotics

Trimethoprim is the most common treatment and is particularly effective, however, there are a wide-range of alternative anti-biotics that can be used.


You can often treat cystitis at home without anti-biotic treatment. There are several things you can do to reduce your symptoms and feel better:

  • Taking over-the-counter painkillers, such as paracetamol and ibuprofen, will help relieve pain. They may also help if you have a fever or a temperature.
  • You can buy over-the-counter medicines to treat your cystitis from a pharmacy. These contain potassium or sodium citrate, which work by making your urine less acidic and therefore reduce discomfort. Always read the patient information leaflet that comes with your medicine and if you have any questions, ask your pharmacist for advice. Check with your GP or pharmacist that these medicines can be taken with any other medication you may be taking.
  • You can also make your urine less acidic by drinking half a glass of water with one teaspoon of bicarbonate of soda dissolved in it, two to three times a day.
  • Increase your intake of fluid to help flush out the infection and dilute your urine.
  • Try not to drink too much alcohol, caffeine or acidic drinks, such as orange juice, as these can irritate your bladder.
  • Placing a hot water bottle on your lower back can help ease discomfort.
  • Try to rest as much as possible.