What causes cystitis?

Cystitis is inflammation of the bladder, usually caused by an infection. It's a common type of urinary tract infection that can lead to uncomfortable and painful urination. Knowing the symptoms and causes of cystitis may help you to avoid it. In this article we explore the causes of cystitis including bacteria and damage to the urethra (where urine leaves the body). As well as when you should see a doctor and what treatments are available. 

What is cystitis?

Cystitis is an inflammation of the bladder which can lead to pain, discomfort when urinating and needing to urinate more often. It is very common amongst women; half of women will experience cystitis at least once in their lives. 

Cystitis is usually very easy to treat, either with over-the-counter painkillers or prescription antibiotics, however there may be times when you should see a doctor. 

Symptoms of cystitis

Most commonly, cystitis presents with:

• pain, stinging or burning when you urinate
• the need to urinate often
• passing small amounts of dark, strong-smelling urine
• traces of blood in your urine
• pain in your belly or in your lower back
• feeling unwell or feverish

These cystitis symptoms usually indicate that you have cystitis, however they can also be caused by other medical conditions and vaginal problems, including sexually transmitted infections. They could also point to vaginal thrush (in women) or prostatitis (in men), if you’re not sure what type of infection you’re experiencing it’s best to speak to your GP. 

Causes of cystitis 

Cystitis is usually caused by a bacterial infection in the bladder which irritates the bladder lining. In most cases the bacterium E.coli which lives in the bowel and is found in poo comes into contact with the urethra (the tube that carries urine out of the body). The bacteria can make their way into the bladder and multiple. 

However you can have symptoms of cystitis without an infection. Cystitis can also be caused by damage to or irritation of the urethra, whether this is through sex or trauma to the urethra. 

Bacterial infection

Urine infections can happen as a result of bacteria being transferred from the anus to the urethra. This is far more common in women than in men, as the female urethra is shorter and closer to the anus. This may be why some women find that they develop cystitis after sex. It’s always a good idea to pee after you’ve had sex. 

In women, bacteria can be spread by wiping from back to front after going to the toilet, inserting a tampon or using a diaphragm. If you experience cystitis and use a diaphragm you might want to think about changing your method of contraception.

Infections can also occur as a result of not emptying your bladder fully when you urinate. If you find that you are not emptying your bladder properly, it might be because of a blockage in your urinary system. Pregnant women can sometimes find it hard to fully empty their bladders as pregnancy can lead to pressure on the pelvic area.

Cystitis can also be more common in women who have been through the menopause, as they produce fewer vaginal secretions, allowing bacteria to multiply.

Damage to the urethra

In both men and women, damage or irritation to the urethra can cause cystitis. Damage to the urethra can cause urine to not leave the body properly or the bladder cannot be emptied fully. 

How do you damage your urethra? 

The urethra can be damaged by a number of events from friction caused by sex to trauma to the area via an accident. There are also health conditions that can increase your risk of developing cystitis. 

• Sex
• Chemical irritants (most commonly fragranced soaps or powders)
• Kidney infections 
• Diabetes
• Damage caused by a catheter
• Menopause - Menopausal women are also at increased risk because they produce less oestrogen, meaning the lining of their bladder and urethra becomes thinner and more prone to damage.

How to avoid cystitis

The best thing to do is familiarise yourself with the cystitis causes listed above and assess whether you might be at risk. Once you have done this, you could try out some preventative methods such as:

• wearing loose cotton underwear
• avoid wearing tight jeans or trousers
• wiping from front to back after going to the toilet
• not holding in urine when you feel the urge to go
• emptying your bladder as soon as possible after having sex
• using unscented soaps to wash around your genitals, and avoiding over-washing
• avoiding constipation

When to see a doctor about cystitis

If you are a woman you should make sure you see your GP if:

• this is the first time you have ever had cystitis
• you have blood in the urine
• you’ve had cystitis 3 or more times in the last 1 year or twice in the last 6 months
• if your symptoms recur within 2 months of completing a course of antibiotics or do not improve after having taken antibiotics
• you are pregnant
• you have a catheter
• you have a condition that suppresses your immune system
• if you have a high fever, severe pain or if your symptoms worsen you should see a doctor immediately

Can men get cystitis? 

Although more women get cystitis than men, men can get cystitis. Symptoms in men include:

• Pain, burning sensation when urinating
• Needing to urinate more often
• Cloudy, dark, strong-smelling urine
• Blood in urine
• Fever

Cystitis is caused by bacteria or damage to the urethra. If you’re a man and think you have cystitis you should see your GP. Cystitis is usually treated with antibiotics, if left untreated it can lead to painful complications such as prostatitis.

Can sex cause cystitis? 

Sex can often be a cause of cystitis. This may be partly due to the movements during sex which may push bacteria up into your bladder. There may also be slight damage to your urethra, which encourages bacteria to thrive. This is more likely if your vagina is dry during sex.

To avoid cystitis, go to the toilet to empty the bladder after sex. If your vagina is dry use a lubricant during sex. The normal mucus in and around your vagina may also be upset if you use spermicides or diaphragm contraceptives, therefore if you suffer from cystitis it might be worth avoiding these and using an alternative method of contraception. If you would like to consider alternative contraceptive options, you can visit our contraception information page or contraception clinic.

Where possible, you should be open with your sexual partner about the precautions you want to take. Remember not to feel embarrassed - cystitis is incredibly common and in most cases nothing to worry about.

Cystitis is not contagious and cannot be passed to your partner during sex.

Can thrush cause cystitis? 

Not usually, however if you have thrush which is causing a lot of itching, irritation, swelling and discomfort which causes you to wipe the area more you could potentially irritate the urethra and cause symptoms of cystitis. However simply having thrush doesn’t mean you’ll develop cystitis. 

How to treat cystitis

In many cases, mild cystitis will pass on its own after a few days. The first time you get cystitis, however, you should always visit your GP. After this you will be familiar with the symptoms and be able to decide whether you require antibiotics or not. If your symptoms are not improving or you think you would like to treat it medically, you can get a prescription for a course of antibiotics from your GP or one of our doctors.

If you are prescribed antibiotics, your symptoms should start to improve after the first day of taking them. If your symptoms don't improve after a course of antibiotics, go back to see your GP.

Read our article on cystitis treatment for more information.

References
https://www.nhsinform.scot/illnesses-and-conditions/kidneys-bladder-and-prostate/cystitis#causes-of-cystitis 
https://www.nhs.uk/conditions/cystitis/ 
https://www.urologyhealth.org/urology-a-z/u/urethral-trauma