Cystitis is an inflammation of the bladder due to a previous bladder infection. Cystitis is a common type of urinary tract infection or UTI. It is particularly common in women as the urethra is smaller in women compared to men, hence the bacteria has to travel a shorter distance to get to the bladder.

Cystitis is not usually a significant medical concern, but it does result in painful and uncomfortable symptoms. There are different levels of severity with cystitis. Mild cystitis usually resolves on its own after a couple of days. Some people can get recurrent cystitis which will need regular or long-term medical treatment as they are clearly at a higher chance of getting infections. If this infection is not managed, it can lead to more severe complications in the future, such as kidney infections. 

Symptoms

The key symptoms of cystitis include: 

  • Pain, burning or stinging on urination (dysuria)

  • Increase frequency in urination 

  • Increase urgency to pee

  • Foul-smelling dark colour urine

  • Lower abdominal pain 

  • Generally feeling unwell 

  • Nausea

Causes

Most cases of cystitis occur due to naturally occurring bacteria found in the bowel or on the skin travelling into the bladder through the urethra. There are other causes behind cystitis, such as:

  • Having intercourse
  • Wiping from the back to the front after going to the toilet (this introduces bacteria from the back end to the front end)
  • Urinary catheters
  • Pregnancy 
  • Using a contraceptive diaphragm 
  • Having diabetes
  • A weakened immune system

The reason why women are more likely to contract cystitis than men as the distance between the anus and the urethra is shorter, and the urethra is smaller in size. Hence this allows the bacteria to enter the bladder more easily.  

Trimethoprim for Cystitis

Trimethoprim is the antibiotic of choice for treating UTIs such as cystitis. It can occasionally be used to treat other infections such as chest infections or acne, but it is normally used for UTIs. Trimethoprim is not available for purchase over the counter and needs a doctor’s prescription. It comes either as a tablet or a drinkable liquid. You can ask your doctor for a specific type based on your preference. 

How to take Trimethoprim

  • It is usually taken 2 times daily for infections (once in the morning and once in the evening)

  • You can take the medication with or without food

  • It takes a couple of days before it takes effects and you feel better

  • You are allowed to drink alcohol while taking Trimethoprim 

  • Trimethoprim is only sold in its generic form.

The course of Trimethoprim prescribed to you entirely depends on the extent and severity of your cystitis, your age and gender. 

  • Women are usually prescribed a 3-day course if they have uncomplicated UTIs

  • Men and pregnant women are usually prescribed a 14-day course if they have uncomplicated UTIs

  • For severe or complicated UTIs, a 14-day course of Trimethoprim is prescribed

If you forget to take a dose of your Trimethoprim, take the missed dose as soon as you remember. If your next dose is coming up, leave the missed dose and take your next dose as per normal. Never take 2 doses at the same time and never take an extra dose to make up for a missed one. 

Contraindications 

Trimethoprim is not suitable for people with certain conditions. If you have any of the following conditions, make sure to let the doctor know. 

  • Allergic to Trimethoprim or any other medications

  • Liver or kidney conditions 

  • Anaemia or low folate levels in the blood 

  • Porphyria (rare inherited blood disorder) or other blood disorders

  • Trying to get pregnant or already pregnant

  • Breastfeeding

Common side effects 

1 in 100 people usually experience these side effects when taking Trimethoprim:

  • Feeling sick 
  • Diarrhoea
  • Headache
  • Mild rash 
  • Itching 

These side effects usually last for a short period and resolve on their own. If these side effects do not resolve or are bothering you let your pharmacist know.